File size: 95,220 Bytes
6fa4bc9
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
{
    "paper_id": "L16-1010",
    "header": {
        "generated_with": "S2ORC 1.0.0",
        "date_generated": "2023-01-19T12:08:43.036056Z"
    },
    "title": "Could Speaker, Gender or Age Awareness be beneficial in Speech-based Emotion Recognition?",
    "authors": [
        {
            "first": "Maxim",
            "middle": [],
            "last": "Sidorov",
            "suffix": "",
            "affiliation": {
                "laboratory": "",
                "institution": "Ulm University",
                "location": {}
            },
            "email": "maxim.sidorov@uni-ulm.de"
        },
        {
            "first": "Alexander",
            "middle": [],
            "last": "Schmitt",
            "suffix": "",
            "affiliation": {
                "laboratory": "",
                "institution": "Ulm University",
                "location": {}
            },
            "email": "alexander.schmitt@uni-ulm.de"
        },
        {
            "first": "Eugene",
            "middle": [],
            "last": "Semenkin",
            "suffix": "",
            "affiliation": {
                "laboratory": "",
                "institution": "Siberian State Aerospace University Ulm Germany",
                "location": {
                    "country": "Krasnoyarsk Russia"
                }
            },
            "email": "eugene.semenkin@sibsau.ru"
        },
        {
            "first": "Wolfgang",
            "middle": [],
            "last": "Minker",
            "suffix": "",
            "affiliation": {
                "laboratory": "",
                "institution": "Ulm University",
                "location": {}
            },
            "email": "wolfgang.minker@uni-ulm.de"
        }
    ],
    "year": "",
    "venue": null,
    "identifiers": {},
    "abstract": "Emotion Recognition (ER) is an important part of dialogue analysis which can be used in order to improve the quality of Spoken Dialogue Systems (SDSs). The emotional hypothesis of the current response of an end-user might be utilised by the dialogue manager component in order to change the SDS strategy which could result in a quality enhancement. In this study additional speaker-related information is used to improve the performance of the speech-based ER process. The analysed information is the speaker identity, gender and age of a user. Two schemes are described here, namely, using additional information as an independent variable within the feature vector and creating separate emotional models for each speaker, gender or age-cluster independently. The performances of the proposed approaches were compared against the baseline ER system, where no additional information has been used, on a number of emotional speech corpora of German, English, Japanese and Russian. The study revealed that for some of the corpora the proposed approach significantly outperforms the baseline methods with a relative difference of up to 11.9%.",
    "pdf_parse": {
        "paper_id": "L16-1010",
        "_pdf_hash": "",
        "abstract": [
            {
                "text": "Emotion Recognition (ER) is an important part of dialogue analysis which can be used in order to improve the quality of Spoken Dialogue Systems (SDSs). The emotional hypothesis of the current response of an end-user might be utilised by the dialogue manager component in order to change the SDS strategy which could result in a quality enhancement. In this study additional speaker-related information is used to improve the performance of the speech-based ER process. The analysed information is the speaker identity, gender and age of a user. Two schemes are described here, namely, using additional information as an independent variable within the feature vector and creating separate emotional models for each speaker, gender or age-cluster independently. The performances of the proposed approaches were compared against the baseline ER system, where no additional information has been used, on a number of emotional speech corpora of German, English, Japanese and Russian. The study revealed that for some of the corpora the proposed approach significantly outperforms the baseline methods with a relative difference of up to 11.9%.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Abstract",
                "sec_num": null
            }
        ],
        "body_text": [
            {
                "text": "By deploying the ER component within the SDS, its quality could be significantly increased. It might be beneficial during human-robot or even human-human interaction. Whereas the majority of studies concentrate on speakerindependent ER experiments, in some cases speakerawareness can bring an additional advantage. Despite the fact that the basic emotions are shared between cultures and nationalities (Scherer, 2002) obviously, each person expresses his emotions individually. This thesis lies behind the idea of building different emotional models for each speaker independently or incorporating the speaker-specific information within the single ER model in a different way. On the one hand it results in a problem-decomposition, similar to the cluster-then-classify approach, but on the other hand by deploying different models for each speaker, the individual features of the corresponding speaker can be caught and utilised properly. Furthermore, as has been mentioned in many studies (Brody, 1985) , (Hall et al., 2000) the gender difference in emotional expression has been detected during several psychological investigations. In contrast to the very specific nature of speaker-adaptive ER, gender-adaptive ER might be more general. A similar idea is behind the age-adaptive ER models, where each user has one of the age-specific labels (for example youth or adult). The global aim of the study is to figure out whether the speaker-, gender-or even age-related information of an enduser might be utilised in order to improve the quality of the ER models. We proposed here a two-stage approach, where firstly the speaker or other additional information (gender or age) is identified and secondly, an adaptive ER procedure is performed. We intend to study both cases: the theoretically possible improvement when the known speakerrelated information is taken into account, and the actual difference, which can be observed by deploying speaker-state recognition models, i.e. Speaker Identification (SI), Gender (GR), or Age Recognition (AR). Thus, in the first case we took the ground-truth information about the speaker, gender and age (the G experiments, for Ground truth), whereas in the second series of experiments we deployed the actual SI, GR, and AR models to estimate the corresponding hypothesis (the E experiments, for Estimated).",
                "cite_spans": [
                    {
                        "start": 402,
                        "end": 417,
                        "text": "(Scherer, 2002)",
                        "ref_id": null
                    },
                    {
                        "start": 991,
                        "end": 1004,
                        "text": "(Brody, 1985)",
                        "ref_id": "BIBREF1"
                    },
                    {
                        "start": 1007,
                        "end": 1026,
                        "text": "(Hall et al., 2000)",
                        "ref_id": "BIBREF9"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Introduction",
                "sec_num": "1."
            },
            {
                "text": "Since the emotions themselves have a subjective nature and generally may vary depending on what language one speaks, we carried out the experiments based on 8 different emotional corpora of English, German, Russian and Japanese in order to gain generalizability of the results obtained. The rest of the paper is organised as follows: Significant related work is presented in 2. Section, whereas 3. Section describes the applied corpora and outlines their differences. Our approach to incorporating the additional speaker-related information within the ER system is presented in 4. Section. The results of numerical experiments are demonstrated in 5. Section. Finally, the conclusion and future work are described in 6. Section.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Introduction",
                "sec_num": "1."
            },
            {
                "text": "The authors in (Lopez-Otero et al., 2015) researched dependencies between speaker-dependent and -independent approaches when the depression level of the speaker is under examination. It has been concluded that the system performance is much better when the test speaker is in both the training and testing sets. Intuitively, the results could be extrapolated in the case of other speaker traits such as emotions, in a similar way to how it was implemented in the case of the speaker identification approach (Kockmann et al., 2011) . The authors in (Vogt and Andr\u00e9, 2006) improved the performance of emotion classification by automatic gender detection. The authors have used two different classifiers in order to classify male and female voices from the Emo-DB (Burkhardt et al., 2005) and the SmartKom (Steininger et al., 2002) corpora. They concluded that the combined gender and emotion recognition system improved the recognition rate of a gender-independent emotion recognition system by 2-4% relatively by applying the Naive Bayes classifier for building the emotion models.",
                "cite_spans": [
                    {
                        "start": 15,
                        "end": 41,
                        "text": "(Lopez-Otero et al., 2015)",
                        "ref_id": "BIBREF13"
                    },
                    {
                        "start": 507,
                        "end": 530,
                        "text": "(Kockmann et al., 2011)",
                        "ref_id": "BIBREF12"
                    },
                    {
                        "start": 548,
                        "end": 570,
                        "text": "(Vogt and Andr\u00e9, 2006)",
                        "ref_id": "BIBREF28"
                    },
                    {
                        "start": 761,
                        "end": 785,
                        "text": "(Burkhardt et al., 2005)",
                        "ref_id": "BIBREF2"
                    },
                    {
                        "start": 803,
                        "end": 828,
                        "text": "(Steininger et al., 2002)",
                        "ref_id": "BIBREF25"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Significant related work",
                "sec_num": "2."
            },
            {
                "text": "All evaluations were conducted using several audio emotional databases. Here is a brief description of them and their statistical characteristics. The AVEC-2014 database was used for the fourth Audio-Visual Emotion Challenge and Workshop 2014 (Valstar et al., 2014) . This corpus is a subset of the AVEC'13 database (Valstar et al., 2013) consisting of 150 videos. Only two tasks in a human-computer interaction scenario have been selected to be included in the dataset. During the Northwind scheme participants read aloud an extract of the story 'The North Wind and the Sun' in German. The Freeform task is participants' answers to several general questions such as 'What was your best gift, and why?', again in German. Each affect dimension (Arousal, Dominance, and Valence) has been annotated separately by a minimum of three and a maximum of five human raters. We averaged the valence and arousal values over the whole recording's duration to obtain only one pair of continuous labels. The Emo-DB emotional database (Burkhardt et al., 2005) was recorded at the Technical University of Berlin and consists of labelled emotional German utterances which were spoken by 10 actors (5 females). 10 German sentences of non-emotional content have been acted by professional actors so that every utterance has one of the following emotional labels: anger, boredom, disgust, anxiety/fear, happiness, sadness and neutral. The total number of utterances in the corpus is 535. The RadioS database consists of recordings from a popular German radio talk-show. Within this corpus, 69 native German speakers talked about their personal troubles. The labelling was performed by a human rater so that each utterance has one of the following emotional labels: neutral, happy, sad and angry.",
                "cite_spans": [
                    {
                        "start": 243,
                        "end": 265,
                        "text": "(Valstar et al., 2014)",
                        "ref_id": "BIBREF27"
                    },
                    {
                        "start": 316,
                        "end": 338,
                        "text": "(Valstar et al., 2013)",
                        "ref_id": "BIBREF26"
                    },
                    {
                        "start": 1020,
                        "end": 1044,
                        "text": "(Burkhardt et al., 2005)",
                        "ref_id": "BIBREF2"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Corpora description",
                "sec_num": "3."
            },
            {
                "text": "The VAM (Grimm et al., 2008) dataset was created at Karlsruhe University and consists of utterances extracted from the popular German talk-show 'Vera am Mittag' (Vera in the afternoon). For this database 12 broadcasts of the talkshow have been recorded. Each broadcast consists of several dialogues of between two and five people each. Continuous emotional labels have been set by evaluators using the valence, activation and dominance basis. The LEGO emotional database (Schmitt et al., 2012) comprises non-acted English (American) utterances which were extracted from the SDS-based bus-stop navigational system (Eskenazi et al., 2008) . The utterances are requests to the system spoken by real users with real concern. Each utterance has one of the following emotional labels: anger, slight anger, much anger, neutral, friendliness and nonspeech -critical noisy recordings or just silence. The corpus was manually annotated by a human rater who chooses one of the labels. We combined all the utterances with different anger levels into a single class with anger labels. Moreover, since there are very few friendly recordings we removed them from the database. As a result we operated only with recordings of 3 labels, namely anger, neutral and non-speech. The SAVEE (Surrey Audio-Visual Expressed Emotion) corpus (Haq and Jackson, 2010 ) was recorded as a part of research into the field of audio-visual emotion classification, from four native English male speakers aged from 27 to 31. The emotional label for each utterance is one of the standard set of emotions (anger, disgust, fear, happiness, sadness, surprise and neutral). The corpus of Russian emotional speech (Makarova and Petrushin, 2002) Ruslana includes records of utterances from 61 subjects (49 females). Each native Russian speaker (aged from 16 to 28 with the average equalling 18.7) read aloud 10 sentences of different content conveying the following six emotional states: neutral, surprise, happiness, anger, sadness and fear. Altogether the database contains 3,660 emotional utterances (61 speakers x 10 sentences x 6 emotional primitives). The UUDB (The Utsunomiya University Spoken Dialogue Database for Paralinguistic Information Studies) database Colours show the optimal classifiers. All the experiments are 10 repetitions of 10-fold cross-validation emotion-stratified. Box-plots with bold frames indicate T-test-based significant differences against the baseline results (at least with p = 0.05).",
                "cite_spans": [
                    {
                        "start": 8,
                        "end": 28,
                        "text": "(Grimm et al., 2008)",
                        "ref_id": "BIBREF8"
                    },
                    {
                        "start": 471,
                        "end": 493,
                        "text": "(Schmitt et al., 2012)",
                        "ref_id": "BIBREF19"
                    },
                    {
                        "start": 613,
                        "end": 636,
                        "text": "(Eskenazi et al., 2008)",
                        "ref_id": "BIBREF5"
                    },
                    {
                        "start": 1315,
                        "end": 1337,
                        "text": "(Haq and Jackson, 2010",
                        "ref_id": "BIBREF10"
                    },
                    {
                        "start": 1672,
                        "end": 1702,
                        "text": "(Makarova and Petrushin, 2002)",
                        "ref_id": "BIBREF14"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Corpora description",
                "sec_num": "3."
            },
            {
                "text": "(Mori et al., 2011) consists of spontaneous Japanese speech through task-oriented dialogue which was produced by 7 pairs of speakers (12 females), 4,737 utterances in total. Emotional labels for each utterance were created by 3 annotators on a 5-dimensional emotional basis: interest (interested-indifferent), credibility (credibledoubtful), dominance (dominant-submissive), arousal (aroused-sleepy) and pleasantness (pleasant-unpleasant). The human raters evaluated the perceived emotional state of the speakers for each utterance on a 7-point scale. Thus, on the pleasantness scale, 1 corresponds to extremely unpleasant, 4 to neutral, and 7 to extremely pleasant. Since a classification task is under consideration, we have used just pleasantness (a synonym for evaluation) and arousal axes from the AVEC-2014, VAM, and UUDB corpora. The corresponding quadrant (anticlockwise, starting in the positive quadrant, assuming arousal as abscissa) can also be assigned emotional labels: happy-exciting, angry-anxious, sad-bored and relaxed-serene (Schuller et al., 2009b) . There is a description of the used corpora in Table 1 .",
                "cite_spans": [
                    {
                        "start": 1044,
                        "end": 1068,
                        "text": "(Schuller et al., 2009b)",
                        "ref_id": "BIBREF21"
                    }
                ],
                "ref_spans": [
                    {
                        "start": 1117,
                        "end": 1124,
                        "text": "Table 1",
                        "ref_id": "TABREF0"
                    }
                ],
                "eq_spans": [],
                "section": "Corpora description",
                "sec_num": "3."
            },
            {
                "text": "Incorporating speaker-specific information into the emotion recognition process may be done in several ways. A very straightforward way is to add this information to the set of features as an additional variable; we will refer to this approach as System Aug for augmented feature vector (Sidorov et al., 2014a) . Another way is to create speakerdependent models: While, for conventional emotion recognition, one statistical model is created independently of the speaker, one may create a separate emotion model for each speaker, we will refer to this approach as System Sep for separate model (Sidorov et al., 2014b) . Both approaches result in a two-stage recognition procedure: First, the speaker is identified and then this information is included into the feature set directly (for the System Aug), or the corresponding emotion model is used for estimating the emotions (for the System Sep). Both emotion recognition-speaker identification hybrid systems have been investigated and evaluated in this study.",
                "cite_spans": [
                    {
                        "start": 287,
                        "end": 310,
                        "text": "(Sidorov et al., 2014a)",
                        "ref_id": "BIBREF22"
                    },
                    {
                        "start": 593,
                        "end": 616,
                        "text": "(Sidorov et al., 2014b)",
                        "ref_id": "BIBREF23"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "The two-stage adaptive emotion recognition",
                "sec_num": "4."
            },
            {
                "text": "To investigate the theoretical improvement of using speaker-specific information for ER, the ground truth information about the speaker has been used (AugG and SepG approaches). Then, in order to perform experiments in realworld conditions, an actual speaker identification component has been applied (AugE and SepE systems). We used a number of classification algorithms, namely k-Nearest Neighbours (KNN) (Cover and Hart, 1967) algorithm (Platt and others, 1999) , and boosted Logistic Regression (LR) (Menard, 2002) , in order to provide statistically reliable and algorithm-independent results. In the first experiment, the focus was on investigating the theoretical improvement, which may be achieved using speaker-based adaptiveness. For this, known speaker information (true labels) was used for both approaches. In System Aug, the speaker information was simply added to the feature vector as an additional variable. Hence, all utterances with the corresponding speaker information were used to create and evaluate an emotion model through the augmented feature vector. For the System Sep, individual emotion models were built for each speaker. During the training phase all speaker utterances were used for creating the emotion models. During testing, all speaker utterances were evaluated with the corresponding emotion model, based on known speaker-related information. Additionally, a second experiment was conducted including an actual speaker identification module instead of using known speaker information. First, a speaker identifier was created during the training phase. Furthermore, for System Aug, the known speaker information was included into the feature vector for the training of the emotion classifier. The testing phase starts with the SI procedure. Then, the speaker hypothesis was included into the feature set which was in turn fed into the emotion recogniser. For System Sep, an emotion recogniser was created for each speaker separately. For testing, the speaker hypothesis of the speaker recognition is used to select the emotion model which corresponds to the recognised speaker to create an emotion hypothesis. In contrast to the first experiment, these experiments are not free of speaker identification errors. Therefore, relatively worse results were expected here. It should be noted that similar experiments have been performed in the case of gender-and age-adaptive studies, where instead of using speaker ID directly (AugG and SepG experiments) and the speaker-identification procedure (AugE and SepE experiments), both gender-and agerelated information, as well as gender-and age-recognition systems have been used correspondingly.",
                "cite_spans": [
                    {
                        "start": 407,
                        "end": 429,
                        "text": "(Cover and Hart, 1967)",
                        "ref_id": "BIBREF3"
                    },
                    {
                        "start": 440,
                        "end": 464,
                        "text": "(Platt and others, 1999)",
                        "ref_id": null
                    },
                    {
                        "start": 504,
                        "end": 518,
                        "text": "(Menard, 2002)",
                        "ref_id": "BIBREF15"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "The two-stage adaptive emotion recognition",
                "sec_num": "4."
            },
            {
                "text": "Within the Sep systems, one may perform normalisation only once for the whole set of utterances, or speakerwise (similarly for gender and age groups). We used Ztransformation, as it was found to perform best for the problem of ER previously (Zhang et al., 2011 ), using both strategies described. Regarding the Aug system, one may consider an augmented feature vector with speaker ID as a unique integer or as a dummy variable (one-hot encoding). When the dummy coding is applied, for all values of the speaker ID attribute a new attribute is created. Next, in every utterance, the new attribute which corresponds to the actual nominal value of the example gets the value 1 and all other new attributes get the value 0. It means that each utterance gets N additional binary variables where N is equal to the number of speakers in the training set, where all the values except for a single one are equal to 0. In such cases when an utterance of an unknown speaker is in the testing set (which could be a case when the number of utterances of this particular speaker is not high enough, provided random emotion-stratified crossvalidation splitting) all new attributes are set to 0. Another aspect is whether these additional speaker-related attributes (either unique integer or dummy variable) should be normalised.",
                "cite_spans": [
                    {
                        "start": 241,
                        "end": 260,
                        "text": "(Zhang et al., 2011",
                        "ref_id": "BIBREF31"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "The two-stage adaptive emotion recognition",
                "sec_num": "4."
            },
            {
                "text": "As a baseline for acoustic features we consider the 384dimensional feature vector which was used within the In-terSpeech 2009 Emotion Challenge (Schuller et al., 2009a) , (Eyben et al., 2010) . We used 10 repetitions of the 10-fold Cross-Validation (CV) emotion-stratified experiment and F 1 measure as a main performance metric. We deployed four machine learning algorithms of different nature to avoid algorithmdependent results. Thus, in the case of speaker identity for the system Sep, we performed 4 (classification algorithms) x 8 (corpora) x 2 (known speaker-related information -SepG vs. estimated one -SepE) x 2 (normalisation once vs. speaker-wise) = 128 experiments, each of them is 10 repetitions of 10-fold cross-validation. For the system Aug, we performed 4 (classification algorithms) x 8 (corpora) x 2 (known speakerrelated information -AugG vs. estimated one -AugE) x 2 (speaker incorporating method -unique integer vs. dummy coding) x 2 (speaker ID normalised vs. non-normalised) = 256 experiments, each of them is 10 repetitions of 10fold cross-validation. It should be noted that gender-related information was available only for 6 corpora, and age-related information was found only within the LEGO corpus, therefore the total number of experiments for genderand age-adaptive ER systems was less than for the speakeradaptive experiments.",
                "cite_spans": [
                    {
                        "start": 144,
                        "end": 168,
                        "text": "(Schuller et al., 2009a)",
                        "ref_id": "BIBREF20"
                    },
                    {
                        "start": 171,
                        "end": 191,
                        "text": "(Eyben et al., 2010)",
                        "ref_id": "BIBREF6"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Numerical evaluations",
                "sec_num": "5."
            },
            {
                "text": "For each experiment we calculated the mean of F 1 measure (over 100 runs, that is -10 repetitions of 10-fold CV) and among 4 classifiers we selected the algorithm with the highest mean. After that, for each combination of normalisation and speaker ID incorporation methods we calculated average ranks, that is -the nominal value depending on the performance of the system on a particular data set, similar to Friedman's statistic (Theodorsson-Norheim, 1987) , (Dem\u0161ar, 2006) . Thus, the best approach will be assigned rank 1, while the runner-up, 2, etc. In the case of identical highest average F 1 measures, we set 1.5 to both approaches. We chose this ranking method due to its simplicity and since it has been observed that the average ranking outperformed more advanced ones, when the performance of classification algorithms was analysed (Brazdil and Soares, 2000) .",
                "cite_spans": [
                    {
                        "start": 430,
                        "end": 457,
                        "text": "(Theodorsson-Norheim, 1987)",
                        "ref_id": null
                    },
                    {
                        "start": 460,
                        "end": 474,
                        "text": "(Dem\u0161ar, 2006)",
                        "ref_id": "BIBREF4"
                    },
                    {
                        "start": 844,
                        "end": 870,
                        "text": "(Brazdil and Soares, 2000)",
                        "ref_id": "BIBREF0"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Numerical evaluations",
                "sec_num": "5."
            },
            {
                "text": "We calculated the ranks separately for the systems which used known speaker-related information and estimated one, as well as for two groups of settings related to Sep and Aug systems, since they have different nature and potentially may result in very different levels of performances. Next, we calculated these ranks for all the corpora considered and used average ranks for the eventual assessment of approaches. Hence, the lower the average rank, the better the system performed on average on all the emotional corpora. For speaker-adaptive systems, the average ranks for the systems Sep and Aug are depicted in Table 2 and in Table 3 , respectively. Subsequently, we selected the systems with the highest ranks to include the corresponding results in graphs. As a visualisation tool we selected a box-plot graph (Williamson et al., 1989) for its high descriptive ability. We used a rather standard declaration of box-plots: the upper hinge is the first quartile (the 25th percentile), the lower hinge is the third quartile (the 75th percentile), upper (lower) whisker -to the highest (lowest) value within 1.5 * IQR (Inter-Quartile Range), points are outliers, lines within boxes depict medians, numbers within boxes are means. Figure 1 depicts the following systems' results for each database: baseline approach -without any additional speaker-related information, SepG and SepE systems performing Z-transformation speaker-wise, AugG system with non-normalised speaker-related attributes within the dummy variable, and AugE approach with normalised speaker-related attributes. We chose these settings due to their highest average ranks (see Table 2 and Table 3 ).",
                "cite_spans": [
                    {
                        "start": 817,
                        "end": 842,
                        "text": "(Williamson et al., 1989)",
                        "ref_id": "BIBREF29"
                    }
                ],
                "ref_spans": [
                    {
                        "start": 616,
                        "end": 638,
                        "text": "Table 2 and in Table 3",
                        "ref_id": "TABREF3"
                    },
                    {
                        "start": 1233,
                        "end": 1241,
                        "text": "Figure 1",
                        "ref_id": "FIGREF0"
                    },
                    {
                        "start": 1647,
                        "end": 1654,
                        "text": "Table 2",
                        "ref_id": "TABREF3"
                    },
                    {
                        "start": 1659,
                        "end": 1666,
                        "text": "Table 3",
                        "ref_id": "TABREF4"
                    }
                ],
                "eq_spans": [],
                "section": "Numerical evaluations",
                "sec_num": "5."
            },
            {
                "text": "Since we did not pay any attention to a significance test while performing the rank calculation, now we performed the paired Student's T-Test, comparing the proposed systems with the baseline approach for each corpus independently. Thus, the box-plots with bold outlines indicate significant difference against the baseline approach with at least p = 0.05. The speaker identification procedure has been performed in such a way, that we used the same algorithm as for the ER task. We used the SI procedure in a corpus-based manner, which means that for each corpus on each iteration of the cross-validation experiments we used exactly the same speech data and features to train both the ER and SI models. Since the results of speaker recognition have changed dramatically depending on the corpus and the algorithms used, we also presented the results of speaker recognition in Figure 2 . Next, we repeated the same experiments for gender-adaptive settings. The average ranks of the systems proposed are depicted in Table 4 and Table 5 . Figure 4 : F 1 measure of speech-based emotion recognition with ground truth age-related information (AugG and SepG), with the estimated age-related hypothesis (AugE and SepE), and without any additional information (baseline). All the experiments are 10 repetitions of 10-fold cross-validation emotion-stratified. Box-plots with bold frames indicate T-test-based significant differences against the baseline results (at least with p = 0.05).",
                "cite_spans": [],
                "ref_spans": [
                    {
                        "start": 876,
                        "end": 884,
                        "text": "Figure 2",
                        "ref_id": "FIGREF1"
                    },
                    {
                        "start": 1014,
                        "end": 1033,
                        "text": "Table 4 and Table 5",
                        "ref_id": "TABREF6"
                    },
                    {
                        "start": 1036,
                        "end": 1044,
                        "text": "Figure 4",
                        "ref_id": null
                    }
                ],
                "eq_spans": [],
                "section": "Numerical evaluations",
                "sec_num": "5."
            },
            {
                "text": "The results, which correspond to the systems with the highest ranks, are depicted in Figure 3 . Finally, we performed age-adaptive experiments on the LEGO corpus since it has age-related information including the following 3 classes: youth, adult and elder. Again, we selected the highest average F 1 measure among all the algorithms considered and depicted the results obtained in Figure 4 . Since only one emotional corpus has been analysed within the age-adaptivity, we did not calculate average ranks for this system.",
                "cite_spans": [],
                "ref_spans": [
                    {
                        "start": 85,
                        "end": 93,
                        "text": "Figure 3",
                        "ref_id": "FIGREF2"
                    },
                    {
                        "start": 382,
                        "end": 390,
                        "text": "Figure 4",
                        "ref_id": null
                    }
                ],
                "eq_spans": [],
                "section": "Numerical evaluations",
                "sec_num": "5."
            },
            {
                "text": "It turned out that in both cases -using actual and estimated speaker identity, the system Sep performed the best with speaker-wise normalisation (see corresponding cells in Table 2 ). Similar results were previously obtained for speech recognition, where speaker normalisation improved the performance of speech recognisers (Giuliani et al., 2006) . Regarding the Aug systems, the one-hot codding performed better than using a unique integer. This was expected due to fact that speaker ID is not numerical but a nominal value and dummy-coding allows this fact to be handled in a more proper way than with a unique integer. Moreover, nonnormalised speaker-related attributes resulted in the best performance within the AugG systems, whereas the normalised version achieved a higher F 1 measure within the AugE system (see corresponding cells in Table 3 ).",
                "cite_spans": [
                    {
                        "start": 324,
                        "end": 347,
                        "text": "(Giuliani et al., 2006)",
                        "ref_id": "BIBREF7"
                    }
                ],
                "ref_spans": [
                    {
                        "start": 173,
                        "end": 180,
                        "text": "Table 2",
                        "ref_id": "TABREF3"
                    },
                    {
                        "start": 844,
                        "end": 851,
                        "text": "Table 3",
                        "ref_id": "TABREF4"
                    }
                ],
                "eq_spans": [],
                "section": "Speaker identity",
                "sec_num": "5.1."
            },
            {
                "text": "The proposed system using an actual SI module resulted in a significant improvement on most of the corpora with a remarkable enhancement of the F 1 measure on the AVEC corpus (49.6 SepE vs. 42.2 baseline), Ruslana (53 AugE vs. 47.3 baseline), and SAVEE (70.1 SepE vs. 63.2 baseline). The results may be even better if the SI component performs more accurately (compare E and G systems in Figure 1) . However, the performances of the Sep system dropped on Emo-DB, LEGO, and Ruslana. In the case of the Emo-DB corpus this can be explained by highly unbalanced coverage of emotions by the speakers. Thus, the speakers ID03 and ID10 have only one single utterance with the disgust label. By using 10-fold CV we ensured that this particular utterance will appear in the testing data exactly once. Let us consider this case and suppose that in a particular iteration of the CV we have the disgust recording in the testing set. When we train the model speaker-wise, then the emotional model for the speaker ID03 and ID10 has no chance to recognise it properly, since during the training phase there were not any recordings with the disgust label. Alternatively, during the baseline approach we operate with the whole training data in order to build only one single emotional model for all the speakers from the training set. It means that the algorithm is trained not only on disgust samples of ID03 or ID10 but all speakers from the training set. Therefore, on each iteration the model could operate with enough samples of all possible labels, enhancing the probability of proper recognition of a particular sample from the testing set.",
                "cite_spans": [],
                "ref_spans": [
                    {
                        "start": 388,
                        "end": 397,
                        "text": "Figure 1)",
                        "ref_id": "FIGREF0"
                    }
                ],
                "eq_spans": [],
                "section": "Speaker identity",
                "sec_num": "5.1."
            },
            {
                "text": "Regarding the LEGO corpus, it was collected from the busnavigation system (see 3. Section) containing real-user requests. Each dialogue consists of from 5 to 9 system-user turns in which the speaker tried to determine an optimal bus-route from the current to the desired location within the city. We supposed that each dialogue had been initiated by a new user and therefore each speaker in the database has very few utterances. As a result, in each iteration of CV we do not have enough data to build a reasonable speaker identification model (see rather poor SI performance on the LEGO in Figure 2 ). Therefore, the performance of the SepE system is much lower than that of the SepG system. The Ruslana corpus contains 10 recordings for each emotional tag for each of 61 speakers. It means that if we perform speaker-dependent modelling for the Sep system, then on each iteration of the CV a modelling algorithm could operate at most with 10 recordings for each emotional label (in this case all the recordings of a particular label should be placed by chance in all the CV folds but not in the one which is currently used for testing) -obviously it is not enough to obtain a reasonable model which would show good generalisation ability. On another hand, the baseline approach operates with the whole set of recordings from all speakers which are in the training set. Therefore, a modelling algorithm within the baseline approach operates with more data of a particular emotional label which in turn lead to higher generalisation ability and recognition performance.",
                "cite_spans": [],
                "ref_spans": [
                    {
                        "start": 591,
                        "end": 599,
                        "text": "Figure 2",
                        "ref_id": "FIGREF1"
                    }
                ],
                "eq_spans": [],
                "section": "Speaker identity",
                "sec_num": "5.1."
            },
            {
                "text": "The results of gender recognition itself were rather high and quite similar for the 4 algorithms used, having an F 1 measure on average (over 4 algorithms) of 97.2 on Emo-DB, 85.7 on LEGO, 93.1 on VAM, 97.1 on UUDB, 94.9 on RadioS, and 98.5 on the Ruslana corpus. It turned out that for the approach which used actual gender information speaker normalisation performed best, whereas for the system with the actual GR component normalisation should be performed only once for all the utterances (see the cor-responding ranks in Table 4 ). Regarding the system Aug, in both cases normalised dummy-based speaker ID encoding resulted in the highest average ranks (see the corresponding ranks in Table 5 ). The results of gender-adaptive ER are more regular, without large variability, and in the case of most corpora resulted in improvement (see Figure 3) .",
                "cite_spans": [],
                "ref_spans": [
                    {
                        "start": 527,
                        "end": 534,
                        "text": "Table 4",
                        "ref_id": "TABREF6"
                    },
                    {
                        "start": 691,
                        "end": 698,
                        "text": "Table 5",
                        "ref_id": "TABREF7"
                    },
                    {
                        "start": 842,
                        "end": 851,
                        "text": "Figure 3)",
                        "ref_id": "FIGREF2"
                    }
                ],
                "eq_spans": [],
                "section": "Gender-awareness",
                "sec_num": "5.2."
            },
            {
                "text": "The result of age recognition itself was equal to 67.7, 70.9, 64.9, and 68.6 using SVM, LR, KNN, and MLP, respectively. However, no improvement on LEGO has been achieved by performing age-adaptiveness (see Figure 4) . We state that more sophisticated experiments with several corpora are needed.",
                "cite_spans": [],
                "ref_spans": [
                    {
                        "start": 206,
                        "end": 215,
                        "text": "Figure 4)",
                        "ref_id": null
                    }
                ],
                "eq_spans": [],
                "section": "Age-awareness",
                "sec_num": "5.3."
            },
            {
                "text": "We concluded that the speaker-adaptive ER can significantly improve the performance using both approaches proposed. However, the Sep system requires balanced data and enough training material of all the target users of the ER system. Moreover, the Sep systems tend to be more sensitive to both the speaker identification error and statistical characteristics of the databases. Indeed, when the Aug systems are applied all of the utterances from the training set are used in order to train the model, whereas only the utterances of the corresponding speaker are used to build the Sep models.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Conclusion and future work",
                "sec_num": "6."
            },
            {
                "text": "In terms of future work, applying multi-agent emotional models can be considered by performing a simple vote or by building a meta-classifier based on individual single classifiers. In this paper we took into account only audio signals, however a dialogue might consist of visual representation, and by analysing visual cues, ER might be more successful. An additional use of advanced machine learning algorithms and contemporary feature selection methods may further improve the ER performance. Specifically, we consider using the deep learning concept to perform ER (Kim et al., 2013) , and the multi-objective genetic algorithm-based feature selection (Sidorov et al., 2015) and state-of-the-art iVector-based SI procedure to further enhance the performance of the ER systems.",
                "cite_spans": [
                    {
                        "start": 568,
                        "end": 586,
                        "text": "(Kim et al., 2013)",
                        "ref_id": "BIBREF11"
                    },
                    {
                        "start": 655,
                        "end": 677,
                        "text": "(Sidorov et al., 2015)",
                        "ref_id": "BIBREF24"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Conclusion and future work",
                "sec_num": "6."
            }
        ],
        "back_matter": [],
        "bib_entries": {
            "BIBREF0": {
                "ref_id": "b0",
                "title": "A comparison of ranking methods for classification algorithm selection",
                "authors": [
                    {
                        "first": "P",
                        "middle": [
                            "B"
                        ],
                        "last": "Brazdil",
                        "suffix": ""
                    },
                    {
                        "first": "C",
                        "middle": [],
                        "last": "Soares",
                        "suffix": ""
                    }
                ],
                "year": 2000,
                "venue": "Machine Learning: ECML 2000",
                "volume": "",
                "issue": "",
                "pages": "63--75",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Brazdil, P. B. and Soares, C. (2000). A comparison of ranking methods for classification algorithm selec- tion. In Machine Learning: ECML 2000, pages 63-75. Springer.",
                "links": null
            },
            "BIBREF1": {
                "ref_id": "b1",
                "title": "Gender differences in emotional development: A review of theories and research",
                "authors": [
                    {
                        "first": "L",
                        "middle": [
                            "R"
                        ],
                        "last": "Brody",
                        "suffix": ""
                    }
                ],
                "year": 1985,
                "venue": "Journal of Personality",
                "volume": "53",
                "issue": "2",
                "pages": "102--149",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Brody, L. R. (1985). Gender differences in emotional de- velopment: A review of theories and research. Journal of Personality, 53(2):102-149.",
                "links": null
            },
            "BIBREF2": {
                "ref_id": "b2",
                "title": "A database of german emotional speech",
                "authors": [
                    {
                        "first": "F",
                        "middle": [],
                        "last": "Burkhardt",
                        "suffix": ""
                    },
                    {
                        "first": "A",
                        "middle": [],
                        "last": "Paeschke",
                        "suffix": ""
                    },
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Rolfes",
                        "suffix": ""
                    },
                    {
                        "first": "W",
                        "middle": [
                            "F"
                        ],
                        "last": "Sendlmeier",
                        "suffix": ""
                    },
                    {
                        "first": "B",
                        "middle": [],
                        "last": "Weiss",
                        "suffix": ""
                    }
                ],
                "year": 2005,
                "venue": "Interspeech",
                "volume": "",
                "issue": "",
                "pages": "1517--1520",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Burkhardt, F., Paeschke, A., Rolfes, M., Sendlmeier, W. F., and Weiss, B. (2005). A database of german emotional speech. In Interspeech, pages 1517-1520.",
                "links": null
            },
            "BIBREF3": {
                "ref_id": "b3",
                "title": "Nearest neighbor pattern classification. Information Theory",
                "authors": [
                    {
                        "first": "T",
                        "middle": [
                            "M"
                        ],
                        "last": "Cover",
                        "suffix": ""
                    },
                    {
                        "first": "P",
                        "middle": [
                            "E"
                        ],
                        "last": "Hart",
                        "suffix": ""
                    }
                ],
                "year": 1967,
                "venue": "IEEE Transactions on",
                "volume": "13",
                "issue": "1",
                "pages": "21--27",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Cover, T. M. and Hart, P. E. (1967). Nearest neighbor pat- tern classification. Information Theory, IEEE Transac- tions on, 13(1):21-27.",
                "links": null
            },
            "BIBREF4": {
                "ref_id": "b4",
                "title": "Statistical comparisons of classifiers over multiple data sets",
                "authors": [
                    {
                        "first": "J",
                        "middle": [],
                        "last": "Dem\u0161ar",
                        "suffix": ""
                    }
                ],
                "year": 2006,
                "venue": "The Journal of Machine Learning Research",
                "volume": "7",
                "issue": "",
                "pages": "1--30",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Dem\u0161ar, J. (2006). Statistical comparisons of classifiers over multiple data sets. The Journal of Machine Learn- ing Research, 7:1-30.",
                "links": null
            },
            "BIBREF5": {
                "ref_id": "b5",
                "title": "Let's go lab: a platform for evaluation of spoken dialog systems with real world users",
                "authors": [
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Eskenazi",
                        "suffix": ""
                    },
                    {
                        "first": "A",
                        "middle": [
                            "W"
                        ],
                        "last": "Black",
                        "suffix": ""
                    },
                    {
                        "first": "A",
                        "middle": [],
                        "last": "Raux",
                        "suffix": ""
                    },
                    {
                        "first": "B",
                        "middle": [],
                        "last": "Langner",
                        "suffix": ""
                    }
                ],
                "year": 2008,
                "venue": "Ninth Annual Conference of the International Speech Communication Association",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Eskenazi, M., Black, A. W., Raux, A., and Langner, B. (2008). Let's go lab: a platform for evaluation of spoken dialog systems with real world users. In Ninth Annual Conference of the International Speech Communication Association.",
                "links": null
            },
            "BIBREF6": {
                "ref_id": "b6",
                "title": "Opensmile: the munich versatile and fast open-source audio feature extractor",
                "authors": [
                    {
                        "first": "F",
                        "middle": [],
                        "last": "Eyben",
                        "suffix": ""
                    },
                    {
                        "first": "M",
                        "middle": [],
                        "last": "W\u00f6llmer",
                        "suffix": ""
                    },
                    {
                        "first": "B",
                        "middle": [],
                        "last": "Schuller",
                        "suffix": ""
                    }
                ],
                "year": 2010,
                "venue": "Proceedings of the international conference on Multimedia",
                "volume": "",
                "issue": "",
                "pages": "1459--1462",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Eyben, F., W\u00f6llmer, M., and Schuller, B. (2010). Opens- mile: the munich versatile and fast open-source audio feature extractor. In Proceedings of the international conference on Multimedia, pages 1459-1462. ACM.",
                "links": null
            },
            "BIBREF7": {
                "ref_id": "b7",
                "title": "Improved automatic speech recognition through speaker normalization",
                "authors": [
                    {
                        "first": "D",
                        "middle": [],
                        "last": "Giuliani",
                        "suffix": ""
                    },
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Gerosa",
                        "suffix": ""
                    },
                    {
                        "first": "F",
                        "middle": [],
                        "last": "Brugnara",
                        "suffix": ""
                    }
                ],
                "year": 2006,
                "venue": "Computer Speech & Language",
                "volume": "20",
                "issue": "1",
                "pages": "107--123",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Giuliani, D., Gerosa, M., and Brugnara, F. (2006). Improved automatic speech recognition through speaker normalization. Computer Speech & Language, 20(1):107-123.",
                "links": null
            },
            "BIBREF8": {
                "ref_id": "b8",
                "title": "The vera am mittag german audio-visual emotional speech database",
                "authors": [
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Grimm",
                        "suffix": ""
                    },
                    {
                        "first": "K",
                        "middle": [],
                        "last": "Kroschel",
                        "suffix": ""
                    },
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Narayanan",
                        "suffix": ""
                    }
                ],
                "year": 2008,
                "venue": "IEEE International Conference on",
                "volume": "",
                "issue": "",
                "pages": "865--868",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Grimm, M., Kroschel, K., and Narayanan, S. (2008). The vera am mittag german audio-visual emotional speech database. In Multimedia and Expo, 2008 IEEE Interna- tional Conference on, pages 865-868. IEEE.",
                "links": null
            },
            "BIBREF9": {
                "ref_id": "b9",
                "title": "Gender differences in nonverbal communication of emotion. Gender and emotion: Social psychological perspectives",
                "authors": [
                    {
                        "first": "J",
                        "middle": [
                            "A"
                        ],
                        "last": "Hall",
                        "suffix": ""
                    },
                    {
                        "first": "J",
                        "middle": [
                            "D"
                        ],
                        "last": "Carter",
                        "suffix": ""
                    },
                    {
                        "first": "T",
                        "middle": [
                            "G"
                        ],
                        "last": "Horgan",
                        "suffix": ""
                    }
                ],
                "year": 2000,
                "venue": "",
                "volume": "",
                "issue": "",
                "pages": "97--117",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Hall, J. A., Carter, J. D., and Horgan, T. G. (2000). Gen- der differences in nonverbal communication of emotion. Gender and emotion: Social psychological perspectives, pages 97-117.",
                "links": null
            },
            "BIBREF10": {
                "ref_id": "b10",
                "title": "Machine Audition: Principles, Algorithms and Systems, chapter Multimodal Emotion Recognition",
                "authors": [
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Haq",
                        "suffix": ""
                    },
                    {
                        "first": "P",
                        "middle": [],
                        "last": "Jackson",
                        "suffix": ""
                    }
                ],
                "year": 2010,
                "venue": "",
                "volume": "",
                "issue": "",
                "pages": "398--423",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Haq, S. and Jackson, P., (2010). Machine Audition: Princi- ples, Algorithms and Systems, chapter Multimodal Emo- tion Recognition, pages 398-423. IGI Global, Hershey PA, Aug.",
                "links": null
            },
            "BIBREF11": {
                "ref_id": "b11",
                "title": "Deep learning for robust feature generation in audiovisual emotion recognition",
                "authors": [
                    {
                        "first": "Y",
                        "middle": [],
                        "last": "Kim",
                        "suffix": ""
                    },
                    {
                        "first": "H",
                        "middle": [],
                        "last": "Lee",
                        "suffix": ""
                    },
                    {
                        "first": "E",
                        "middle": [
                            "M"
                        ],
                        "last": "Provost",
                        "suffix": ""
                    }
                ],
                "year": 2013,
                "venue": "Acoustics, Speech and Signal Processing (ICASSP), 2013 IEEE International Conference on",
                "volume": "",
                "issue": "",
                "pages": "3687--3691",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Kim, Y., Lee, H., and Provost, E. M. (2013). Deep learn- ing for robust feature generation in audiovisual emotion recognition. In Acoustics, Speech and Signal Process- ing (ICASSP), 2013 IEEE International Conference on, pages 3687-3691. IEEE.",
                "links": null
            },
            "BIBREF12": {
                "ref_id": "b12",
                "title": "Application of speaker-and language identification state-of-the-art techniques for emotion recognition",
                "authors": [
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Kockmann",
                        "suffix": ""
                    },
                    {
                        "first": "L",
                        "middle": [],
                        "last": "Burget",
                        "suffix": ""
                    }
                ],
                "year": 2011,
                "venue": "Speech Communication",
                "volume": "53",
                "issue": "9",
                "pages": "1172--1185",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Kockmann, M., Burget, L., et al. (2011). Application of speaker-and language identification state-of-the-art tech- niques for emotion recognition. Speech Communication, 53(9):1172-1185.",
                "links": null
            },
            "BIBREF13": {
                "ref_id": "b13",
                "title": "Assessing speaker independence on a speech-based depression level estimation system",
                "authors": [
                    {
                        "first": "P",
                        "middle": [],
                        "last": "Lopez-Otero",
                        "suffix": ""
                    },
                    {
                        "first": "L",
                        "middle": [],
                        "last": "Docio-Fernandez",
                        "suffix": ""
                    },
                    {
                        "first": "C",
                        "middle": [],
                        "last": "Garcia-Mateo",
                        "suffix": ""
                    }
                ],
                "year": 2015,
                "venue": "",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Lopez-Otero, P., Docio-Fernandez, L., and Garcia-Mateo, C. (2015). Assessing speaker independence on a speech-based depression level estimation system. Pat- tern Recognition Letters.",
                "links": null
            },
            "BIBREF14": {
                "ref_id": "b14",
                "title": "Ruslana: A database of russian emotional utterances",
                "authors": [
                    {
                        "first": "V",
                        "middle": [],
                        "last": "Makarova",
                        "suffix": ""
                    },
                    {
                        "first": "V",
                        "middle": [],
                        "last": "Petrushin",
                        "suffix": ""
                    }
                ],
                "year": 2002,
                "venue": "Proc. Int. Conf. Spoken Language Processing",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Makarova, V. and Petrushin, V. (2002). Ruslana: A database of russian emotional utterances. In Proc. Int. Conf. Spoken Language Processing (ICSLP 2002).",
                "links": null
            },
            "BIBREF15": {
                "ref_id": "b15",
                "title": "Applied logistic regression analysis",
                "authors": [
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Menard",
                        "suffix": ""
                    }
                ],
                "year": 2002,
                "venue": "",
                "volume": "106",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Menard, S. (2002). Applied logistic regression analysis, volume 106. Sage.",
                "links": null
            },
            "BIBREF16": {
                "ref_id": "b16",
                "title": "Constructing a spoken dialogue corpus for studying paralinguistic information in expressive conversation and analyzing its statistical/acoustic characteristics",
                "authors": [
                    {
                        "first": "H",
                        "middle": [],
                        "last": "Mori",
                        "suffix": ""
                    },
                    {
                        "first": "T",
                        "middle": [],
                        "last": "Satake",
                        "suffix": ""
                    },
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Nakamura",
                        "suffix": ""
                    },
                    {
                        "first": "H",
                        "middle": [],
                        "last": "Kasuya",
                        "suffix": ""
                    }
                ],
                "year": 2011,
                "venue": "Speech Communication",
                "volume": "53",
                "issue": "1",
                "pages": "36--50",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Mori, H., Satake, T., Nakamura, M., and Kasuya, H. (2011). Constructing a spoken dialogue corpus for studying paralinguistic information in expressive conver- sation and analyzing its statistical/acoustic characteris- tics. Speech Communication, 53(1):36-50.",
                "links": null
            },
            "BIBREF17": {
                "ref_id": "b17",
                "title": "Fast training of support vector machines using sequential minimal optimization",
                "authors": [
                    {
                        "first": "J",
                        "middle": [],
                        "last": "Platt",
                        "suffix": ""
                    }
                ],
                "year": 1999,
                "venue": "Advances in kernel methodssupport vector learning",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Platt, J. et al. (1999). Fast training of support vector ma- chines using sequential minimal optimization. Advances in kernel methodssupport vector learning, 3.",
                "links": null
            },
            "BIBREF19": {
                "ref_id": "b19",
                "title": "A parameterized and annotated spoken dialog corpus of the cmu let's go bus information system",
                "authors": [
                    {
                        "first": "A",
                        "middle": [],
                        "last": "Schmitt",
                        "suffix": ""
                    },
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Ultes",
                        "suffix": ""
                    },
                    {
                        "first": "W",
                        "middle": [],
                        "last": "Minker",
                        "suffix": ""
                    }
                ],
                "year": 2012,
                "venue": "LREC",
                "volume": "",
                "issue": "",
                "pages": "3369--3373",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Schmitt, A., Ultes, S., and Minker, W. (2012). A param- eterized and annotated spoken dialog corpus of the cmu let's go bus information system. In LREC, pages 3369- 3373.",
                "links": null
            },
            "BIBREF20": {
                "ref_id": "b20",
                "title": "The interspeech 2009 emotion challenge",
                "authors": [
                    {
                        "first": "B",
                        "middle": [],
                        "last": "Schuller",
                        "suffix": ""
                    },
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Steidl",
                        "suffix": ""
                    },
                    {
                        "first": "A",
                        "middle": [],
                        "last": "Batliner",
                        "suffix": ""
                    }
                ],
                "year": 2009,
                "venue": "INTERSPEECH",
                "volume": "",
                "issue": "",
                "pages": "312--315",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Schuller, B., Steidl, S., and Batliner, A. (2009a). The in- terspeech 2009 emotion challenge. In INTERSPEECH, volume 2009, pages 312-315.",
                "links": null
            },
            "BIBREF21": {
                "ref_id": "b21",
                "title": "Acoustic emotion recognition: A benchmark comparison of performances",
                "authors": [
                    {
                        "first": "B",
                        "middle": [],
                        "last": "Schuller",
                        "suffix": ""
                    },
                    {
                        "first": "B",
                        "middle": [],
                        "last": "Vlasenko",
                        "suffix": ""
                    },
                    {
                        "first": "F",
                        "middle": [],
                        "last": "Eyben",
                        "suffix": ""
                    },
                    {
                        "first": "G",
                        "middle": [],
                        "last": "Rigoll",
                        "suffix": ""
                    },
                    {
                        "first": "A",
                        "middle": [],
                        "last": "Wendemuth",
                        "suffix": ""
                    }
                ],
                "year": 2009,
                "venue": "Automatic Speech Recognition & Understanding",
                "volume": "",
                "issue": "",
                "pages": "552--557",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Schuller, B., Vlasenko, B., Eyben, F., Rigoll, G., and Wendemuth, A. (2009b). Acoustic emotion recogni- tion: A benchmark comparison of performances. In Automatic Speech Recognition & Understanding, 2009. ASRU 2009. IEEE Workshop on, pages 552-557. IEEE.",
                "links": null
            },
            "BIBREF22": {
                "ref_id": "b22",
                "title": "Comparison of gender-and speaker-adaptive emotion recognition",
                "authors": [
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Sidorov",
                        "suffix": ""
                    },
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Ultes",
                        "suffix": ""
                    },
                    {
                        "first": "A",
                        "middle": [],
                        "last": "Schmitt",
                        "suffix": ""
                    }
                ],
                "year": 2014,
                "venue": "International Conference on Language Resources and Evaluation (LREC)",
                "volume": "",
                "issue": "",
                "pages": "3476--3480",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Sidorov, M., Ultes, S., and Schmitt, A. (2014a). Compari- son of gender-and speaker-adaptive emotion recognition. International Conference on Language Resources and Evaluation (LREC), pages 3476-3480.",
                "links": null
            },
            "BIBREF23": {
                "ref_id": "b23",
                "title": "Emotions are a personal thing: Towards speaker-adaptive emotion recognition",
                "authors": [
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Sidorov",
                        "suffix": ""
                    },
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Ultes",
                        "suffix": ""
                    },
                    {
                        "first": "A",
                        "middle": [],
                        "last": "Schmitt",
                        "suffix": ""
                    }
                ],
                "year": 2014,
                "venue": "Acoustics, Speech and Signal Processing (ICASSP)",
                "volume": "",
                "issue": "",
                "pages": "4803--4807",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Sidorov, M., Ultes, S., and Schmitt, A. (2014b). Emotions are a personal thing: Towards speaker-adaptive emotion recognition. In Acoustics, Speech and Signal Process- ing (ICASSP), 2014 IEEE International Conference on, pages 4803-4807. IEEE.",
                "links": null
            },
            "BIBREF24": {
                "ref_id": "b24",
                "title": "Contemporary stochastic feature selection algorithms for speechbased emotion recognition",
                "authors": [
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Sidorov",
                        "suffix": ""
                    },
                    {
                        "first": "C",
                        "middle": [],
                        "last": "Brester",
                        "suffix": ""
                    },
                    {
                        "first": "A",
                        "middle": [],
                        "last": "Schmitt",
                        "suffix": ""
                    }
                ],
                "year": 2015,
                "venue": "Proceedings of the Annual Conference of the International Speech Communication Association (INTERSPEECH)",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Sidorov, M., Brester, C., and Schmitt, A. (2015). Contem- porary stochastic feature selection algorithms for speech- based emotion recognition. In Proceedings of the An- nual Conference of the International Speech Commu- nication Association (INTERSPEECH), Dresden, Ger- many, September.",
                "links": null
            },
            "BIBREF25": {
                "ref_id": "b25",
                "title": "Friedman and quade tests: Basic computer program to perform nonparametric two-way analysis of variance and multiple comparisons on ranks of several related samples",
                "authors": [
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Steininger",
                        "suffix": ""
                    },
                    {
                        "first": "F",
                        "middle": [],
                        "last": "Schiel",
                        "suffix": ""
                    },
                    {
                        "first": "O",
                        "middle": [],
                        "last": "Dioubina",
                        "suffix": ""
                    },
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Raubold",
                        "suffix": ""
                    }
                ],
                "year": 1987,
                "venue": "LREC Workshop on \"Multimodal Resources",
                "volume": "17",
                "issue": "",
                "pages": "85--99",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Steininger, S., Schiel, F., Dioubina, O., and Raubold, S. (2002). Development of user-state conventions for the multimodal corpus in smartkom. In LREC Workshop on \"Multimodal Resources\", Las Palmas, Spain. Theodorsson-Norheim, E. (1987). Friedman and quade tests: Basic computer program to perform nonparametric two-way analysis of variance and multiple comparisons on ranks of several related samples. Computers in biol- ogy and medicine, 17(2):85-99.",
                "links": null
            },
            "BIBREF26": {
                "ref_id": "b26",
                "title": "Avec 2013: the continuous audio/visual emotion and depression recognition challenge",
                "authors": [
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Valstar",
                        "suffix": ""
                    },
                    {
                        "first": "B",
                        "middle": [],
                        "last": "Schuller",
                        "suffix": ""
                    },
                    {
                        "first": "K",
                        "middle": [],
                        "last": "Smith",
                        "suffix": ""
                    },
                    {
                        "first": "F",
                        "middle": [],
                        "last": "Eyben",
                        "suffix": ""
                    },
                    {
                        "first": "B",
                        "middle": [],
                        "last": "Jiang",
                        "suffix": ""
                    },
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Bilakhia",
                        "suffix": ""
                    },
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Schnieder",
                        "suffix": ""
                    },
                    {
                        "first": "R",
                        "middle": [],
                        "last": "Cowie",
                        "suffix": ""
                    },
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Pantic",
                        "suffix": ""
                    }
                ],
                "year": 2013,
                "venue": "Proceedings of the 3rd ACM international workshop on Audio/visual emotion challenge",
                "volume": "",
                "issue": "",
                "pages": "3--10",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Valstar, M., Schuller, B., Smith, K., Eyben, F., Jiang, B., Bilakhia, S., Schnieder, S., Cowie, R., and Pantic, M. (2013). Avec 2013: the continuous audio/visual emotion and depression recognition challenge. In Proceedings of the 3rd ACM international workshop on Audio/visual emotion challenge, pages 3-10. ACM.",
                "links": null
            },
            "BIBREF27": {
                "ref_id": "b27",
                "title": "Avec 2014: 3d dimensional affect and depression recognition challenge",
                "authors": [
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Valstar",
                        "suffix": ""
                    },
                    {
                        "first": "B",
                        "middle": [],
                        "last": "Schuller",
                        "suffix": ""
                    },
                    {
                        "first": "K",
                        "middle": [],
                        "last": "Smith",
                        "suffix": ""
                    },
                    {
                        "first": "T",
                        "middle": [],
                        "last": "Almaev",
                        "suffix": ""
                    },
                    {
                        "first": "F",
                        "middle": [],
                        "last": "Eyben",
                        "suffix": ""
                    },
                    {
                        "first": "J",
                        "middle": [],
                        "last": "Krajewski",
                        "suffix": ""
                    },
                    {
                        "first": "R",
                        "middle": [],
                        "last": "Cowie",
                        "suffix": ""
                    },
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Pantic",
                        "suffix": ""
                    }
                ],
                "year": 2014,
                "venue": "Proceedings of the 4th International Workshop on Audio/Visual Emotion Challenge",
                "volume": "",
                "issue": "",
                "pages": "3--10",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Valstar, M., Schuller, B., Smith, K., Almaev, T., Eyben, F., Krajewski, J., Cowie, R., and Pantic, M. (2014). Avec 2014: 3d dimensional affect and depression recognition challenge. In Proceedings of the 4th International Work- shop on Audio/Visual Emotion Challenge, pages 3-10. ACM.",
                "links": null
            },
            "BIBREF28": {
                "ref_id": "b28",
                "title": "Improving automatic emotion recognition from speech via gender differentiation",
                "authors": [
                    {
                        "first": "T",
                        "middle": [],
                        "last": "Vogt",
                        "suffix": ""
                    },
                    {
                        "first": "E",
                        "middle": [],
                        "last": "Andr\u00e9",
                        "suffix": ""
                    }
                ],
                "year": 2006,
                "venue": "Proc. Language Resources and Evaluation Conference (LREC 2006)",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Vogt, T. and Andr\u00e9, E. (2006). Improving automatic emo- tion recognition from speech via gender differentiation. In Proc. Language Resources and Evaluation Confer- ence (LREC 2006), Genoa. Citeseer.",
                "links": null
            },
            "BIBREF29": {
                "ref_id": "b29",
                "title": "The box plot: a simple visual method to interpret data",
                "authors": [
                    {
                        "first": "D",
                        "middle": [
                            "F"
                        ],
                        "last": "Williamson",
                        "suffix": ""
                    },
                    {
                        "first": "R",
                        "middle": [
                            "A"
                        ],
                        "last": "Parker",
                        "suffix": ""
                    },
                    {
                        "first": "J",
                        "middle": [
                            "S"
                        ],
                        "last": "Kendrick",
                        "suffix": ""
                    }
                ],
                "year": 1989,
                "venue": "Annals of internal medicine",
                "volume": "110",
                "issue": "11",
                "pages": "916--921",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Williamson, D. F., Parker, R. A., and Kendrick, J. S. (1989). The box plot: a simple visual method to interpret data. Annals of internal medicine, 110(11):916-921.",
                "links": null
            },
            "BIBREF30": {
                "ref_id": "b30",
                "title": "Introduction to statistical learning theory and support vector machines",
                "authors": [
                    {
                        "first": "Z",
                        "middle": [],
                        "last": "Xuegong",
                        "suffix": ""
                    }
                ],
                "year": 2000,
                "venue": "Acta Automatica Sinica",
                "volume": "26",
                "issue": "1",
                "pages": "32--42",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Xuegong, Z. (2000). Introduction to statistical learning theory and support vector machines. Acta Automatica Sinica, 26(1):32-42.",
                "links": null
            },
            "BIBREF31": {
                "ref_id": "b31",
                "title": "Unsupervised learning in cross-corpus acoustic emotion recognition",
                "authors": [
                    {
                        "first": "Z",
                        "middle": [],
                        "last": "Zhang",
                        "suffix": ""
                    },
                    {
                        "first": "F",
                        "middle": [],
                        "last": "Weninger",
                        "suffix": ""
                    },
                    {
                        "first": "M",
                        "middle": [],
                        "last": "W\u00f6llmer",
                        "suffix": ""
                    },
                    {
                        "first": "B",
                        "middle": [],
                        "last": "Schuller",
                        "suffix": ""
                    }
                ],
                "year": 2011,
                "venue": "Automatic Speech Recognition and Understanding (ASRU)",
                "volume": "",
                "issue": "",
                "pages": "523--528",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Zhang, Z., Weninger, F., W\u00f6llmer, M., and Schuller, B. (2011). Unsupervised learning in cross-corpus acoustic emotion recognition. In Automatic Speech Recognition and Understanding (ASRU), 2011 IEEE Workshop on, pages 523-528. IEEE.",
                "links": null
            }
        },
        "ref_entries": {
            "FIGREF0": {
                "text": "F 1 measure of speech-based emotion recognition with ground-truth speaker-related information (AugG and SepG), with the estimated speaker-related hypothesis (AugE and SepE), and without any additional information (baseline).",
                "uris": null,
                "num": null,
                "type_str": "figure"
            },
            "FIGREF1": {
                "text": "F 1 measure of speech-based speaker recognition. All the experiments are 10 repetitions of 10-fold crossvalidation emotion-stratified. Values within the graphs are average F 1 measures.",
                "uris": null,
                "num": null,
                "type_str": "figure"
            },
            "FIGREF2": {
                "text": "F 1 measure of speech-based emotion recognition with ground-truth gender-related information (AugG and SepG), with the estimated gender-related hypothesis (AugE and SepE), and without any additional information (baseline). Colours show the optimal classifiers. All the experiments are 10 repetitions of 10-fold cross-validation emotion-stratified. Box-plots with bold frames indicate T-test-based significant differences against the baseline results (at least with p = 0.05).",
                "uris": null,
                "num": null,
                "type_str": "figure"
            },
            "TABREF0": {
                "type_str": "table",
                "text": "Databases description.",
                "html": null,
                "num": null,
                "content": "<table/>"
            },
            "TABREF3": {
                "type_str": "table",
                "text": "Ranks of Sep while speaker-adaptiveness is under examination.",
                "html": null,
                "num": null,
                "content": "<table><tr><td/><td/><td>AugG</td><td/></tr><tr><td/><td>Dummy</td><td>Unique</td><td/></tr><tr><td colspan=\"4\">Non-norm Norm Non-norm Norm</td></tr><tr><td>1.5</td><td>1.63</td><td>3.19</td><td>3.69</td></tr><tr><td/><td/><td>AugE</td><td/></tr><tr><td/><td>Dummy</td><td>Unique</td><td/></tr><tr><td colspan=\"4\">Non-norm Norm Non-norm Norm</td></tr><tr><td>2.06</td><td>1.81</td><td>2.56</td><td>3.56</td></tr></table>"
            },
            "TABREF4": {
                "type_str": "table",
                "text": "Ranks of Aug while speaker-adaptiveness is under examination.",
                "html": null,
                "num": null,
                "content": "<table/>"
            },
            "TABREF6": {
                "type_str": "table",
                "text": "Ranks of Sep for gender-adaptive ER.",
                "html": null,
                "num": null,
                "content": "<table><tr><td/><td/><td>AugG</td><td/></tr><tr><td/><td>Dummy</td><td>Unique</td><td/></tr><tr><td colspan=\"4\">Non-norm Norm Non-norm Norm</td></tr><tr><td>2.66</td><td>1.92</td><td>3.08</td><td>2.33</td></tr><tr><td/><td/><td>AugE</td><td/></tr><tr><td/><td>Dummy</td><td>Unique</td><td/></tr><tr><td colspan=\"4\">Non-norm Norm Non-norm Norm</td></tr><tr><td>2.42</td><td>2</td><td>3.08</td><td>2.5</td></tr></table>"
            },
            "TABREF7": {
                "type_str": "table",
                "text": "Ranks of Aug for gender-adaptive ER.",
                "html": null,
                "num": null,
                "content": "<table/>"
            }
        }
    }
}