File size: 90,325 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
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
{
    "paper_id": "P06-1035",
    "header": {
        "generated_with": "S2ORC 1.0.0",
        "date_generated": "2023-01-19T09:23:25.474100Z"
    },
    "title": "Measuring Language Divergence by Intra-Lexical Comparison",
    "authors": [
        {
            "first": "T",
            "middle": [
                "Mark"
            ],
            "last": "Ellison",
            "suffix": "",
            "affiliation": {
                "laboratory": "",
                "institution": "Informatics University of Edinburgh",
                "location": {}
            },
            "email": ""
        },
        {
            "first": "Simon",
            "middle": [],
            "last": "Kirby",
            "suffix": "",
            "affiliation": {
                "laboratory": "Language Evolution and Computation Research Unit Philosophy, Psychology and Language Sciences",
                "institution": "University of Edinburgh",
                "location": {}
            },
            "email": ""
        }
    ],
    "year": "",
    "venue": null,
    "identifiers": {},
    "abstract": "This paper presents a method for building genetic language taxonomies based on a new approach to comparing lexical forms. Instead of comparing forms cross-linguistically, a matrix of languageinternal similarities between forms is calculated. These matrices are then compared to give distances between languages. We argue that this coheres better with current thinking in linguistics and psycholinguistics. An implementation of this approach, called PHILOLOGICON, is described, along with its application to Dyen et al.'s (1992) ninety-five wordlists from Indo-European languages.",
    "pdf_parse": {
        "paper_id": "P06-1035",
        "_pdf_hash": "",
        "abstract": [
            {
                "text": "This paper presents a method for building genetic language taxonomies based on a new approach to comparing lexical forms. Instead of comparing forms cross-linguistically, a matrix of languageinternal similarities between forms is calculated. These matrices are then compared to give distances between languages. We argue that this coheres better with current thinking in linguistics and psycholinguistics. An implementation of this approach, called PHILOLOGICON, is described, along with its application to Dyen et al.'s (1992) ninety-five wordlists from Indo-European languages.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Abstract",
                "sec_num": null
            }
        ],
        "body_text": [
            {
                "text": "Recently, there has been burgeoning interest in the computational construction of genetic language taxonomies (Dyen et al., 1992; Nerbonne and Heeringa, 1997; Kondrak, 2002; Ringe et al., 2002; Benedetto et al., 2002; McMahon and McMahon, 2003; Gray and Atkinson, 2003; Nakleh et al., 2005) .",
                "cite_spans": [
                    {
                        "start": 110,
                        "end": 129,
                        "text": "(Dyen et al., 1992;",
                        "ref_id": "BIBREF4"
                    },
                    {
                        "start": 130,
                        "end": 158,
                        "text": "Nerbonne and Heeringa, 1997;",
                        "ref_id": "BIBREF21"
                    },
                    {
                        "start": 159,
                        "end": 173,
                        "text": "Kondrak, 2002;",
                        "ref_id": "BIBREF13"
                    },
                    {
                        "start": 174,
                        "end": 193,
                        "text": "Ringe et al., 2002;",
                        "ref_id": "BIBREF24"
                    },
                    {
                        "start": 194,
                        "end": 217,
                        "text": "Benedetto et al., 2002;",
                        "ref_id": "BIBREF3"
                    },
                    {
                        "start": 218,
                        "end": 244,
                        "text": "McMahon and McMahon, 2003;",
                        "ref_id": "BIBREF17"
                    },
                    {
                        "start": 245,
                        "end": 269,
                        "text": "Gray and Atkinson, 2003;",
                        "ref_id": "BIBREF6"
                    },
                    {
                        "start": 270,
                        "end": 290,
                        "text": "Nakleh et al., 2005)",
                        "ref_id": "BIBREF20"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Introduction",
                "sec_num": "1"
            },
            {
                "text": "One common approach to building language taxonomies is to ascribe language-language distances, and then use a generic algorithm to construct a tree which explains these distances as much as possible. Two questions arise with this approach. The first asks what aspects of languages are important in measuring inter-language distance. The second asks how to measure distance given these aspects.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Introduction",
                "sec_num": "1"
            },
            {
                "text": "A more traditional approach to building language taxonomies (Dyen et al., 1992) answers these questions in terms of cognates. A word in language A is said to be cognate with word in language B if the forms shared a common ancestor in the parent language of A and B. In the cognatecounting method, inter-language distance depends on the lexical forms of the languages. The distance between two languages is a function of the number or fraction of these forms which are cognate between the two languages 1 . This approach to building language taxonomies is hard to implement in toto because constructing ancestor forms is not easily automatable.",
                "cite_spans": [
                    {
                        "start": 60,
                        "end": 79,
                        "text": "(Dyen et al., 1992)",
                        "ref_id": "BIBREF4"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Introduction",
                "sec_num": "1"
            },
            {
                "text": "More recent approaches, such as Kondrak's (2002) and work on dialect comparison, take the synchronic word forms themselves as the language aspect to be compared. Variations on edit distance (see Kessler (2005) for a survey) are then used to evaluate differences between languages for each word, and these differences are aggregated to give a distance between languages or dialects as a whole. This approach is largely automatable, although some methods do require human intervention.",
                "cite_spans": [
                    {
                        "start": 32,
                        "end": 48,
                        "text": "Kondrak's (2002)",
                        "ref_id": "BIBREF13"
                    },
                    {
                        "start": 195,
                        "end": 209,
                        "text": "Kessler (2005)",
                        "ref_id": "BIBREF11"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Introduction",
                "sec_num": "1"
            },
            {
                "text": "In this paper, we present novel answers to the two questions. The features of language we will compare are not sets of words or phonological forms. Instead we compare the similarities between forms, expressed as confusion probabilities. The distribution of confusion probabilities in one language is called a lexical metric. Section 2 presents the definition of lexical metrics and some arguments for their being good language representatives for the purposes of comparison.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Introduction",
                "sec_num": "1"
            },
            {
                "text": "The distance between two languages is the divergence their lexical metrics. In section 3, we detail two methods for measuring this divergence: Kullback-Liebler (herafter KL) divergence and Rao distance. The subsequent section (4) describes the application of our approach to automatically constructing a taxonomy of Indo-European languages from Dyen et al. (1992) data.",
                "cite_spans": [
                    {
                        "start": 345,
                        "end": 363,
                        "text": "Dyen et al. (1992)",
                        "ref_id": "BIBREF4"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Introduction",
                "sec_num": "1"
            },
            {
                "text": "Section 5 suggests how lexical metrics can help identify cognates. The final section (6) presents our conclusions, and discusses possible future directions for this work.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Introduction",
                "sec_num": "1"
            },
            {
                "text": "Versions of the software and data files described in the paper will be made available to coincide with its publication.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Introduction",
                "sec_num": "1"
            },
            {
                "text": "The first question posed by the distance-based approach to genetic language taxonomy is: what should we compare?",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2"
            },
            {
                "text": "In some approaches (Kondrak, 2002; Nerbonne and Heeringa, 1997) , the answer to this question is that we should compare the phonetic or phonological realisations of a particular set of meanings across the range of languages being studied. There are a number of problems with using lexical forms in this way.",
                "cite_spans": [
                    {
                        "start": 19,
                        "end": 34,
                        "text": "(Kondrak, 2002;",
                        "ref_id": "BIBREF13"
                    },
                    {
                        "start": 35,
                        "end": 63,
                        "text": "Nerbonne and Heeringa, 1997)",
                        "ref_id": "BIBREF21"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2"
            },
            {
                "text": "Firstly, in order to compare forms from different languages, we need to embed them in common phonetic space. This phonetic space provides granularity, marking two phones as identical or distinct, and where there is a graded measure of phonetic distinction it measures this.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2"
            },
            {
                "text": "There is growing doubt in the field of phonology and phonetics about the meaningfulness of assuming of a common phonetic space. Port and Leary (2005) argue convincingly that this assumption, while having played a fundamental role in much recent linguistic theorising, is nevertheless unfounded. The degree of difference between sounds, and consequently, the degree of phonetic difference between words can only be ascertained within the context of a single language.",
                "cite_spans": [
                    {
                        "start": 128,
                        "end": 149,
                        "text": "Port and Leary (2005)",
                        "ref_id": null
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2"
            },
            {
                "text": "It may be argued that a common phonetic space can be found in either acoustics or degrees of freedom in the speech articulators. Language-specific categorisation of sound, however, often restructures this space, sometimes with distinct sounds being treated as homophones. One example of this is the realisation of orthographic rr in European Portuguese: it is indifferently realised with an apical or a uvular trill, different sounds made at distinct points of articulation.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2"
            },
            {
                "text": "If there is no language-independent, common phonetic space with an equally common similarity measure, there can be no principled approach to comparing forms in one language with those of another.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2"
            },
            {
                "text": "In contrast, language-specific word-similarity is well-founded. A number of psycholinguistic models of spoken word recognition (Luce et al., 1990) are based on the idea of lexical neighbourhoods. When a word is accessed during processing, the other words that are phonemically or orthographically similar are also activated. This effect can be detected using experimental paradigms such as priming.",
                "cite_spans": [
                    {
                        "start": 127,
                        "end": 146,
                        "text": "(Luce et al., 1990)",
                        "ref_id": "BIBREF16"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2"
            },
            {
                "text": "Our approach, therefore, is to abandon the cross-linguistic comparison of phonetic realisations, in favour of language-internal comparison of forms. (See also work by Shillcock et al. (2001) and Tamariz (2005) ).",
                "cite_spans": [
                    {
                        "start": 167,
                        "end": 190,
                        "text": "Shillcock et al. (2001)",
                        "ref_id": "BIBREF27"
                    },
                    {
                        "start": 195,
                        "end": 209,
                        "text": "Tamariz (2005)",
                        "ref_id": "BIBREF29"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2"
            },
            {
                "text": "One psychologically well-grounded way of describing the similarity of words is in terms of their confusion probabilities. Two words have high confusion probability if it is likely that one word could be produced or understood when the other was intended. This type of confusion can be measured experimentally by giving subjects words in noisy environments and measuring what they apprehend.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Confusion probabilities",
                "sec_num": "2.1"
            },
            {
                "text": "A less pathological way in which confusion probability is realised is in coactivation. If a person hears a word, then they more easily and more quickly recognise similar words. This coactivation occurs because the phonological realisation of words is not completely separate in the mind. Instead, realisations are interdependent with realisations of similar words.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Confusion probabilities",
                "sec_num": "2.1"
            },
            {
                "text": "We propose that confusion probabilities are ideal information to constitute the lexical metric. They are language-specific, psychologically grounded, can be determined by experiment, and integrate with existing psycholinguistic models of word recognition.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Confusion probabilities",
                "sec_num": "2.1"
            },
            {
                "text": "Unfortunately, experimentally determined confusion probabilities for a large number of languages are not available. Fortunately, models of spoken word recognition allow us to predict these probabilities from easily-computable measures of word similarity.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "For example, the neighbourhood activation model (NAM) (Luce et al., 1990; Luce and Pisoni, 1998) predicts confusion probabilities from the relative frequency of words in the neighbourhood of the target. Words are in the neighbourhood of the target if their Levenstein (1965) edit distance from the target is one. The more frequent the word is, the greater its likelihood of replacing the target.",
                "cite_spans": [
                    {
                        "start": 54,
                        "end": 73,
                        "text": "(Luce et al., 1990;",
                        "ref_id": "BIBREF16"
                    },
                    {
                        "start": 74,
                        "end": 96,
                        "text": "Luce and Pisoni, 1998)",
                        "ref_id": "BIBREF15"
                    },
                    {
                        "start": 257,
                        "end": 274,
                        "text": "Levenstein (1965)",
                        "ref_id": "BIBREF14"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "Bailey and Hahn 2001argue, however, that the all-or-nothing nature of the lexical neighbourhood is insufficient. Instead word similarity is the complex function of frequency and phonetic similarity shown in equation 1. Here A, B, C and D are constants of the model, u and v are words, and d is a phonetic similarity model. .d(u,v) ( 1)We have adapted this model slightly, in line with NAM, taking the similarity s to be the probability of confusing stimulus v with form u. Also, as our data usually offers no frequency information, we have adopted the maximum entropy assumption, namely, that all relative frequencies are equal. Consequently, the probability of confusion of two words depends solely on their similarity distance. While this assumption degrades the psychological reality of the model, it does not render it useless, as the similarity measure continues to provide important distinctions in neighbourhood confusability.",
                "cite_spans": [
                    {
                        "start": 323,
                        "end": 330,
                        "text": ".d(u,v)",
                        "ref_id": null
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "s = (AF (u) 2 + BF (u) + C)e \u2212D",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "We also assume for simplicity, that the constant D has the value 1.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "With these simplifications, equation 2shows the probability of apprehending word w, out of a set W of possible alternatives, given a stimulus word w s .",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "EQUATION",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [
                    {
                        "start": 0,
                        "end": 8,
                        "text": "EQUATION",
                        "ref_id": "EQREF",
                        "raw_str": "P (w|w s ) = e \u2212d(w,ws) /N (w s )",
                        "eq_num": "(2)"
                    }
                ],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "The normalising constant N (s) is the sum of the non-normalised values for e \u2212d(w,ws) for all words w. u,v) 2.3 Scaled edit distances Kidd and Watson (1992) have shown that discriminability of frequency and of duration of tones in a tone sequence depends on its length as a proportion of the length of the sequence. Kapatsinski (2006) uses this, with other evidence, to argue that word recognition edit distances must be scaled by word-length.",
                "cite_spans": [
                    {
                        "start": 103,
                        "end": 107,
                        "text": "u,v)",
                        "ref_id": null
                    },
                    {
                        "start": 134,
                        "end": 156,
                        "text": "Kidd and Watson (1992)",
                        "ref_id": "BIBREF12"
                    },
                    {
                        "start": 316,
                        "end": 334,
                        "text": "Kapatsinski (2006)",
                        "ref_id": "BIBREF10"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "N (w s ) = w\u2208W e \u2212d(",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "There are other reasons for coming to the same conclusion. The simple Levenstein distance exaggerates the disparity between long words in comparison with short words. A word of consisting of 10 symbols, purely by virtue of its length, will on average be marked as more different from other words than a word of length two. For example, Levenstein distance between interested and rest is six, the same as the distance between rest and by, even though the latter two have nothing in common. As a consequence, close phonetic transcriptions, which by their very nature are likely to involve more symbols per word, will result in larger edit distances than broad phonemic transcriptions of the same data.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "To alleviate this problem, we define a new edit distance function d 2 which scales Levenstein distances by the average length of the words being compared (see equation 3). Now the distance between interested and rest is 0.86, while that between rest and by is 2.0, reflecting the greater relative difference in the second pair.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "EQUATION",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [
                    {
                        "start": 0,
                        "end": 8,
                        "text": "EQUATION",
                        "ref_id": "EQREF",
                        "raw_str": "d 2 (w 2 , w 1 ) = 2d(w 2 , w 1 ) |w 1 | + |w 2 |",
                        "eq_num": "(3)"
                    }
                ],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "Note that by scaling the raw edit distance with the average lengths of the words, we are preserving the symmetric property of the distance measure.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "There are other methods of comparing strings, for example string kernels (Shawe-Taylor and Cristianini, 2004) , but using Levenstein distance keeps us coherent with the psycholinguistic accounts of word similarity.",
                "cite_spans": [
                    {
                        "start": 73,
                        "end": 109,
                        "text": "(Shawe-Taylor and Cristianini, 2004)",
                        "ref_id": "BIBREF25"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "NAM and beyond",
                "sec_num": "2.2"
            },
            {
                "text": "Bringing this all together, we can define the lexical metric.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2.4"
            },
            {
                "text": "A lexicon L is a mapping from a set of meanings M , such as \"DOG\", \"TO RUN\", \"GREEN\", etc., onto a set F of forms such as /pies/, /biec/, /zielony/.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2.4"
            },
            {
                "text": "The confusion probability P of m 1 for m 2 in lexical L is the normalised negative exponential of the scaled edit-distance of the corresponding forms. It is worth noting that when frequencies are assumed to follow the maximum entropy distribution, this connection between confusion probabilities and distances (see equation 4) is the same as that proposed by Shepard (1987) .",
                "cite_spans": [
                    {
                        "start": 359,
                        "end": 373,
                        "text": "Shepard (1987)",
                        "ref_id": "BIBREF26"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2.4"
            },
            {
                "text": "EQUATION",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [
                    {
                        "start": 0,
                        "end": 8,
                        "text": "EQUATION",
                        "ref_id": "EQREF",
                        "raw_str": "P (m 1 |m 2 ; L) = e \u2212d 2 (L(m 1 ),L(m 2 )) N (m 2 ; L)",
                        "eq_num": "(4)"
                    }
                ],
                "section": "Lexical Metric",
                "sec_num": "2.4"
            },
            {
                "text": "A lexical metric of L is the mapping LM (L) : M 2 \u2192 [0, 1] which assigns to each pair of meanings m 1 , m 2 the probability of confusing m 1 for m 2 , scaled by the frequency of m 2 .",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2.4"
            },
            {
                "text": "LM (L)(m 1 , m 2 ) = P (L(m 1 )|L(m 2 ))P (m 2 ) = e \u2212d 2 (L(m 1 ),L(m 2 )) N (m 2 ; L)|M | where N (m 2 ; L)",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2.4"
            },
            {
                "text": "is the normalising function defined in equation 5. inferred word confusion probabilities. The matrix is normalised so that the sum of each row is 0.2, ie. one-fifth for each of the five words, so the total of the matrix is one. Note that the diagonal values vary because the off-diagonal values in each row vary, and consequently, so does the normalisation for the row.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Lexical Metric",
                "sec_num": "2.4"
            },
            {
                "text": "EQUATION",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [
                    {
                        "start": 0,
                        "end": 8,
                        "text": "EQUATION",
                        "ref_id": "EQREF",
                        "raw_str": "N (m 2 ; L) = m\u2208M e \u2212d 2 (L(m),L(m 2 ))",
                        "eq_num": "(5)"
                    }
                ],
                "section": "Lexical Metric",
                "sec_num": "2.4"
            },
            {
                "text": "In the previous section, we introduced the lexical metric as the key measurable for comparing languages. Since lexical metrics are probability distributions, comparison of metrics means measuring the difference between probability distributions. To do this, we use two measures: the symmetric Kullback-Liebler divergence (Jeffreys, 1946) and the Rao distance (Rao, 1949; Atkinson and Mitchell, 1981; Micchelli and Noakes, 2005) based on Fisher Information (Fisher, 1959) . These can be defined in terms the geometric path from one distribution to another.",
                "cite_spans": [
                    {
                        "start": 321,
                        "end": 337,
                        "text": "(Jeffreys, 1946)",
                        "ref_id": "BIBREF9"
                    },
                    {
                        "start": 359,
                        "end": 370,
                        "text": "(Rao, 1949;",
                        "ref_id": "BIBREF23"
                    },
                    {
                        "start": 371,
                        "end": 399,
                        "text": "Atkinson and Mitchell, 1981;",
                        "ref_id": "BIBREF0"
                    },
                    {
                        "start": 400,
                        "end": 427,
                        "text": "Micchelli and Noakes, 2005)",
                        "ref_id": "BIBREF19"
                    },
                    {
                        "start": 456,
                        "end": 470,
                        "text": "(Fisher, 1959)",
                        "ref_id": "BIBREF5"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Language-Language Distance",
                "sec_num": "3"
            },
            {
                "text": "The geometric path between two distributions P and Q is a conditional distribution R with a continuous parameter \u03b1 such that at \u03b1 = 0, the distribution is P , and at \u03b1 = 1 it is Q. This conditional distribution is called the geometric because it consists of normalised weighted geometric means of the two defining distributions (equation 6).",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Geometric paths",
                "sec_num": "3.1"
            },
            {
                "text": "R(w|\u03b1) = P (w) \u03b1 Q(w) 1\u2212\u03b1 /k(\u03b1; P, Q) 6The function k(\u03b1; P, Q) is a normaliser for the conditional distribution, being the sum of the weighted geometric means of values from P and Q (equation 7). This value is known as the Chernoff coefficient or Helliger path (Basseville, 1989) . For brevity, the P, Q arguments to k will be treated as implicit and not expressed in equations.",
                "cite_spans": [
                    {
                        "start": 261,
                        "end": 279,
                        "text": "(Basseville, 1989)",
                        "ref_id": "BIBREF2"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Geometric paths",
                "sec_num": "3.1"
            },
            {
                "text": "EQUATION",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [
                    {
                        "start": 0,
                        "end": 8,
                        "text": "EQUATION",
                        "ref_id": "EQREF",
                        "raw_str": "k(\u03b1) = w\u2208W 2 P (w) 1\u2212\u03b1 Q(w) \u03b1",
                        "eq_num": "(7)"
                    }
                ],
                "section": "Geometric paths",
                "sec_num": "3.1"
            },
            {
                "text": "The first-order (equation 8) differential of the normaliser with regard to \u03b1 is of particular interest.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Kullback-Liebler distance",
                "sec_num": "3.2"
            },
            {
                "text": "k \u2032 (\u03b1) = w\u2208W 2 log Q(w) P (w) P (w) 1\u2212\u03b1 Q(w) \u03b1 (8)",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Kullback-Liebler distance",
                "sec_num": "3.2"
            },
            {
                "text": "At \u03b1 = 0, this value is the negative of the Kullback-Liebler distance KL(P |Q) of Q with regard to P (Basseville, 1989) . At \u03b1 = 1, it is the Kullback-Liebler distance KL(Q|P ) of P with regard to Q. Jeffreys' (1946) measure is a symmetrisation of KL distance, by averaging the commutations (equations 9,10).",
                "cite_spans": [
                    {
                        "start": 101,
                        "end": 119,
                        "text": "(Basseville, 1989)",
                        "ref_id": "BIBREF2"
                    },
                    {
                        "start": 200,
                        "end": 216,
                        "text": "Jeffreys' (1946)",
                        "ref_id": "BIBREF9"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Kullback-Liebler distance",
                "sec_num": "3.2"
            },
            {
                "text": "EQUATION",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [
                    {
                        "start": 0,
                        "end": 8,
                        "text": "EQUATION",
                        "ref_id": "EQREF",
                        "raw_str": "= KL(Q|P ) + KL(P |Q) 2 (9) = k \u2032 (1) \u2212 k \u2032 (0) 2",
                        "eq_num": "(10)"
                    }
                ],
                "section": "KL(P, Q)",
                "sec_num": null
            },
            {
                "text": "Rao distance depends on the second-order (equation 11) differential of the normaliser with regard to \u03b1.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Rao distance",
                "sec_num": "3.3"
            },
            {
                "text": "EQUATION",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [
                    {
                        "start": 0,
                        "end": 8,
                        "text": "EQUATION",
                        "ref_id": "EQREF",
                        "raw_str": "k \u2032\u2032 (\u03b1) = w\u2208W 2 log 2 Q(w) P (w) P (w) 1\u2212\u03b1 Q(w) \u03b1",
                        "eq_num": "(11)"
                    }
                ],
                "section": "Rao distance",
                "sec_num": "3.3"
            },
            {
                "text": "Fisher information is defined as in equation 12.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Rao distance",
                "sec_num": "3.3"
            },
            {
                "text": "F I(P, x) = \u2212 \u2202 2 log P (y|x) \u2202x 2 P (y|x)dy (12)",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Rao distance",
                "sec_num": "3.3"
            },
            {
                "text": "Equation (13) expresses Fisher information along the path R from P to Q at point \u03b1 using k and its first two derivatives.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Rao distance",
                "sec_num": "3.3"
            },
            {
                "text": "FI(R, \u03b1) = k(\u03b1)k \u2032\u2032 (\u03b1) \u2212 k \u2032 (\u03b1) 2 k(\u03b1) 2 (13)",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Rao distance",
                "sec_num": "3.3"
            },
            {
                "text": "The Rao distance r(P, Q) along R can be approximated by the square root of the Fisher information at the path's midpoint \u03b1 = 0.5. r(P, Q) = k(0.5)k \u2032\u2032 (0.5) \u2212 k \u2032 (0.5) 2 k(0.5) 2 (14)",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Rao distance",
                "sec_num": "3.3"
            },
            {
                "text": "Bringing these pieces together, the PHILOLOGI-CON algorithm for measuring the divergence between two languages has the following steps:",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "The PHILOLOGICON algorithm",
                "sec_num": "3.4"
            },
            {
                "text": "1. determine their joint confusion probability matrices, P and Q, 2. substitute these into equation 7, equation 8and equation 11to calculate k(0), k(0.5), k(1), k \u2032 (0.5), and k \u2032\u2032 (0.5),",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "The PHILOLOGICON algorithm",
                "sec_num": "3.4"
            },
            {
                "text": "3. and put these into equation 10and equation 14to calculate the KL and Rao distances between between the languages.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "The PHILOLOGICON algorithm",
                "sec_num": "3.4"
            },
            {
                "text": "The ideal data for reconstructing Indo-European would be an accurate phonemic transcription of words used to express specifically defined meanings. Sadly, this kind of data is not readily available. However, as a stop-gap measure, we can adopt the data that Dyen et al. collected to construct a Indo-European taxonomy using the cognate method. Dyen et al. (1992) collected 95 data sets, each pairing a meaning from a Swadesh (1952)-like 200word list with its expression in the corresponding language. The compilers annotated with data with cognacy relations, as part of their own taxonomic analysis of Indo-European. There are problems with using Dyen's data for the purposes of the current paper. Firstly, the word forms collected are not phonetic, phonological or even full orthographic representations. As the authors state, the forms are expressed in sufficient detail to allow an interested reader acquainted with the language in question to identify which word is being expressed.",
                "cite_spans": [
                    {
                        "start": 344,
                        "end": 362,
                        "text": "Dyen et al. (1992)",
                        "ref_id": "BIBREF4"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Indo-European",
                "sec_num": "4"
            },
            {
                "text": "Secondly, many meanings offer alternative forms, presumably corresponding to synonyms. For a human analyst using the cognate approach, this means that a language can participate in two (or more) word-derivation systems. In preparing this data for processing, we have consistently chosen the first of any alternatives.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Dyen et al's data",
                "sec_num": "4.1"
            },
            {
                "text": "A further difficulty lies in the fact that many languages are not represented by the full 200 meanings. Consequently, in comparing lexical metrics from two data sets, we frequently need to restrict the metrics to only those meanings expressed in both the sets. This means that the KL divergence or the Rao distance between two languages were measured on lexical metrics cropped and rescaled to the meanings common to both data-sets. In most cases, this was still more than 190 words.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Dyen et al's data",
                "sec_num": "4.1"
            },
            {
                "text": "Despite these mismatches between Dyen et al.'s data and our needs, it provides an testbed for the PHILOLOGICON algorithm. Our reasoning being, that if successful with this data, the method is reasonably reliable. Data was extracted to languagespecific files, and preprocessed to clean up problems such as those described above. An additional data-set was added with random data to act as an outlier to root the tree.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Dyen et al's data",
                "sec_num": "4.1"
            },
            {
                "text": "PHILOLOGICON software was then used to calculate the lexical metrics corresponding to the individual data files and to measure KL divergences and Rao distances between them. The program NEIGHBOR from the PHYLIP 2 package was used to construct trees from the results.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Processing the data",
                "sec_num": "4.2"
            },
            {
                "text": "The tree based on Rao distances is shown in figure 1. The discussion follows this tree except in those few cases mentioning differences in the KL tree.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "The results",
                "sec_num": "4.3"
            },
            {
                "text": "The standard against which we measure the success of our trees is the conservative traditional taxonomy to be found in the Ethnologue (Grimes and Grimes, 2000) . The fit with this taxonomy was so good that we have labelled the major branches with their traditional names: Celtic, Germanic, etc. In fact, in most cases, the branchinternal divisions -eg. Brythonic/Goidelic in Celtic, Western/Eastern/Southern in Slavic, or Western/Northern in Germanic -also accord. Note that PHILOLOGICON even groups Baltic and Slavic together into a super-branch Balto-Slavic.",
                "cite_spans": [
                    {
                        "start": 134,
                        "end": 159,
                        "text": "(Grimes and Grimes, 2000)",
                        "ref_id": "BIBREF7"
                    }
                ],
                "ref_spans": [],
                "eq_spans": [],
                "section": "The results",
                "sec_num": "4.3"
            },
            {
                "text": "Where languages are clearly out of place in comparison to the traditional taxonomy, these are highlighted: visually in the tree, and verbally in the following text. In almost every case, there are obvious contact phenomena which explain the deviation from the standard taxonomy.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "The results",
                "sec_num": "4.3"
            },
            {
                "text": "Armenian was grouped with the Indo-Iranian languages. Interestingly, Armenian was at first thought to be an Iranian language, as it shares much vocabulary with these languages. The common vocabulary is now thought to be the result of borrowing, rather than common genetic origin. In the KL tree, Armenian is placed outside of the Indo-Iranian languages, except for Gypsy. On the other hand, in this tree, Ossetic is placed as an outlier of the Indian group, while its traditional classification (and the Rao distance tree) puts it among the Iranian languages. Gypsy is an Indian language, related to Hindi. It has, however, been surrounded by European languages for some centuries. The effects of this influence is the likely cause for it being classified as an outlier in the Indo-Iranian family. A similar situation exists for Slavic: one of the two lists that Dyen et al. offer for Slovenian is classed as an outlier in Slavic, rather than classifying it with the Southern Slavic languages. The other Slovenian list is classified correctly with Serbocroatian. It is possible that the significant impact of Italian on Slovenian has made it an outlier. In Germanic, it is English that is the outlier. This may be due to the impact of the English creole, Takitaki, on the hierarchy. This language is closest to English, but is very distinct from the rest of the Germanic languages. Another misclassification also is the result of contact phenomena. According to the Ethnologue, Sardinian is Southern Romance, a separate branch from Italian or from Spanish. However, its constant contact with Italian has influenced the language such that it is classified here with Italian. We can offer no explanation for why Wakhi ends up an outlier to all the groups.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "The results",
                "sec_num": "4.3"
            },
            {
                "text": "In conclusion, despite the noisy state of Dyen et al.'s data (for our purposes), the PHILOLOGICON generates a taxonomy close to that constructed using the traditional methods of historical linguistics. Where it deviates, the deviation usually points to identifiable contact between languages. ",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "The results",
                "sec_num": "4.3"
            },
            {
                "text": "Subsection 3.1 described the construction of geometric paths from one lexical metric to another. This section describes how the synthetic lexical metric at the midpoint of the path can indicate which words are cognate between the two languages.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Reconstruction and Cognacy",
                "sec_num": "5"
            },
            {
                "text": "The synthetic lexical metric (equation 15) applies the formula for the geometric path equation (6) to the lexical metrics equation (5) of the languages being compared, at the midpoint \u03b1 = 0.5.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Reconstruction and Cognacy",
                "sec_num": "5"
            },
            {
                "text": "EQUATION",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [
                    {
                        "start": 0,
                        "end": 8,
                        "text": "EQUATION",
                        "ref_id": "EQREF",
                        "raw_str": "R 1 2 (m 1 , m 2 ) = P (m 1 |m 2 )Q(m 1 |m 2 ) |M |k( 1 2 )",
                        "eq_num": "(15)"
                    }
                ],
                "section": "Reconstruction and Cognacy",
                "sec_num": "5"
            },
            {
                "text": "If the words for m 1 and m 2 in both languages have common origins in a parent language, then it is reasonable to expect that their confusion probabilities in both languages will be similar. Of course different cognate pairs m 1 , m 2 will have differing values for R, but the confusion probabilities in P and Q will be similar, and consequently, the reinforce the variance. If either m 1 or m 2 , or both, is non-cognate, that is, has been replaced by another arbitrary form at some point in the history of either language, then the P and Q for this pair will take independently varying values. Consequently, the geometric mean of these values is likely to take a value more closely bound to the average, than in the purely cognate case.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "Reconstruction and Cognacy",
                "sec_num": "5"
            },
            {
                "text": "Thus rows in the lexical metric with wider dynamic ranges are likely to correspond to cognate words. Rows corresponding to non-cognates are likely to have smaller dynamic ranges. The dynamic range can be measured by taking the Shannon information of the probabilities in the row. Table 2 shows the most low-and highinformation rows from English and Swedish (Dyen et al's (1992) data). At the extremes of low and high information, the words are invariably cognate and non-cognate. Between these extremes, the division is not so clear cut, due to chance effects in the data.",
                "cite_spans": [
                    {
                        "start": 357,
                        "end": 377,
                        "text": "(Dyen et al's (1992)",
                        "ref_id": "BIBREF4"
                    }
                ],
                "ref_spans": [
                    {
                        "start": 280,
                        "end": 287,
                        "text": "Table 2",
                        "ref_id": null
                    }
                ],
                "eq_spans": [],
                "section": "Reconstruction and Cognacy",
                "sec_num": "5"
            },
            {
                "text": "In this paper, we have presented a distancebased method, called PHILOLOGICON, that constructs genetic trees on the basis of lexica from each language. The method only compares words language-internally, where comparison seems both psychologically real and reliable, Table 2 : Shannon information of confusion distributions in the reconstruction of English and Swedish. Information levels are shown translated so that the average is zero.",
                "cite_spans": [],
                "ref_spans": [
                    {
                        "start": 266,
                        "end": 273,
                        "text": "Table 2",
                        "ref_id": null
                    }
                ],
                "eq_spans": [],
                "section": "Conclusions and Future Directions",
                "sec_num": "6"
            },
            {
                "text": "and never cross-linguistically, where comparison is less well-founded. It uses measures founded in information theory to compare the intra-lexical differences.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "English",
                "sec_num": null
            },
            {
                "text": "The method successfully, if not perfectly, recreated the phylogenetic tree of Indo-European languages on the basis of noisy data. In further work, we plan to improve both the quantity and the quality of the data. Since most of the mis-placements on the tree could be accounted for by contact phenomena, it is possible that a network-drawing, rather than tree-drawing, analysis would produce better results.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "English",
                "sec_num": null
            },
            {
                "text": "Likewise, we plan to develop the method for identifying cognates. The key improvement needed is a way to distinguish indeterminate distances in reconstructed lexical metrics from determinate but uniform ones. This may be achieved by retaining information about the distribution of the original values which were combined to form the reconstructed metric.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "English",
                "sec_num": null
            },
            {
                "text": "McMahon and McMahon (2003) for an account of treeinference from the cognate percentages in theDyen et al. (1992) data.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "",
                "sec_num": null
            },
            {
                "text": "See http://evolution.genetics.washington.edu/phylip.html.",
                "cite_spans": [],
                "ref_spans": [],
                "eq_spans": [],
                "section": "",
                "sec_num": null
            }
        ],
        "back_matter": [],
        "bib_entries": {
            "BIBREF0": {
                "ref_id": "b0",
                "title": "Rao's distance measure",
                "authors": [
                    {
                        "first": "C",
                        "middle": [],
                        "last": "Atkinson",
                        "suffix": ""
                    },
                    {
                        "first": "A",
                        "middle": [
                            "F S"
                        ],
                        "last": "Mitchell",
                        "suffix": ""
                    }
                ],
                "year": 1981,
                "venue": "",
                "volume": "4",
                "issue": "",
                "pages": "345--365",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "C. Atkinson and A.F.S. Mitchell. 1981. Rao's distance measure. Sankhy\u0101, 4:345-365.",
                "links": null
            },
            "BIBREF1": {
                "ref_id": "b1",
                "title": "Determinants of wordlikeness: Phonotactics or lexical neighborhoods?",
                "authors": [
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Todd",
                        "suffix": ""
                    },
                    {
                        "first": "Ulrike",
                        "middle": [],
                        "last": "Bailey",
                        "suffix": ""
                    },
                    {
                        "first": "",
                        "middle": [],
                        "last": "Hahn",
                        "suffix": ""
                    }
                ],
                "year": 2001,
                "venue": "Journal of Memory and Language",
                "volume": "44",
                "issue": "",
                "pages": "568--591",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Todd M. Bailey and Ulrike Hahn. 2001. Determinants of wordlikeness: Phonotactics or lexical neighbor- hoods? Journal of Memory and Language, 44:568- 591.",
                "links": null
            },
            "BIBREF2": {
                "ref_id": "b2",
                "title": "Distance measures for signal processing and pattern recognition",
                "authors": [
                    {
                        "first": "Michle",
                        "middle": [],
                        "last": "Basseville",
                        "suffix": ""
                    }
                ],
                "year": 1989,
                "venue": "",
                "volume": "18",
                "issue": "",
                "pages": "349--369",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Michle Basseville. 1989. Distance measures for signal processing and pattern recognition. Signal Process- ing, 18(4):349-369, December.",
                "links": null
            },
            "BIBREF3": {
                "ref_id": "b3",
                "title": "Language trees and zipping",
                "authors": [
                    {
                        "first": "D",
                        "middle": [],
                        "last": "Benedetto",
                        "suffix": ""
                    },
                    {
                        "first": "E",
                        "middle": [],
                        "last": "Caglioti",
                        "suffix": ""
                    },
                    {
                        "first": "V",
                        "middle": [],
                        "last": "Loreto",
                        "suffix": ""
                    }
                ],
                "year": 2002,
                "venue": "Physical Review Letters",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "D. Benedetto, E. Caglioti, and V. Loreto. 2002. Lan- guage trees and zipping. Physical Review Letters, 88.",
                "links": null
            },
            "BIBREF4": {
                "ref_id": "b4",
                "title": "An indo-european classification: a lexicostatistical experiment",
                "authors": [
                    {
                        "first": "Isidore",
                        "middle": [],
                        "last": "Dyen",
                        "suffix": ""
                    },
                    {
                        "first": "Joseph",
                        "middle": [
                            "B"
                        ],
                        "last": "Kruskal",
                        "suffix": ""
                    },
                    {
                        "first": "Paul",
                        "middle": [],
                        "last": "Black",
                        "suffix": ""
                    }
                ],
                "year": 1992,
                "venue": "Transactions of the American Philosophical Society",
                "volume": "",
                "issue": "5",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Isidore Dyen, Joseph B. Kruskal, and Paul Black. 1992. An indo-european classification: a lexicosta- tistical experiment. Transactions of the American Philosophical Society, 82(5).",
                "links": null
            },
            "BIBREF5": {
                "ref_id": "b5",
                "title": "Statistical Methods and Scientific Inference",
                "authors": [
                    {
                        "first": "R",
                        "middle": [
                            "A"
                        ],
                        "last": "Fisher",
                        "suffix": ""
                    }
                ],
                "year": 1959,
                "venue": "",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "R.A. Fisher. 1959. Statistical Methods and Scientific Inference. Oliver and Boyd, London.",
                "links": null
            },
            "BIBREF6": {
                "ref_id": "b6",
                "title": "Language-tree divergence times support the anatolian theory of indo-european origin",
                "authors": [
                    {
                        "first": "Russell",
                        "middle": [
                            "D"
                        ],
                        "last": "Gray",
                        "suffix": ""
                    },
                    {
                        "first": "Quentin",
                        "middle": [
                            "D"
                        ],
                        "last": "Atkinson",
                        "suffix": ""
                    }
                ],
                "year": 2003,
                "venue": "Nature",
                "volume": "426",
                "issue": "",
                "pages": "435--439",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Russell D. Gray and Quentin D. Atkinson. 2003. Language-tree divergence times support the ana- tolian theory of indo-european origin. Nature, 426:435-439.",
                "links": null
            },
            "BIBREF7": {
                "ref_id": "b7",
                "title": "Ethnologue: Languages of the World",
                "authors": [
                    {
                        "first": "B",
                        "middle": [
                            "F"
                        ],
                        "last": "Grimes",
                        "suffix": ""
                    },
                    {
                        "first": "J",
                        "middle": [
                            "E"
                        ],
                        "last": "Grimes",
                        "suffix": ""
                    }
                ],
                "year": 2000,
                "venue": "SIL International",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "B.F. Grimes and J.E. Grimes, editors. 2000. Ethno- logue: Languages of the World. SIL International, 14th edition.",
                "links": null
            },
            "BIBREF8": {
                "ref_id": "b8",
                "title": "Perspectives on Variation, chapter From phonetic similarity to dialect classification",
                "authors": [
                    {
                        "first": "Paul",
                        "middle": [],
                        "last": "Heggarty",
                        "suffix": ""
                    },
                    {
                        "first": "April",
                        "middle": [],
                        "last": "Mcmahon",
                        "suffix": ""
                    },
                    {
                        "first": "Robert",
                        "middle": [],
                        "last": "Mcmahon",
                        "suffix": ""
                    }
                ],
                "year": 2005,
                "venue": "",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Paul Heggarty, April McMahon, and Robert McMa- hon, 2005. Perspectives on Variation, chapter From phonetic similarity to dialect classification. Mouton de Gruyter.",
                "links": null
            },
            "BIBREF9": {
                "ref_id": "b9",
                "title": "An invariant form for the prior probability in estimation problems",
                "authors": [
                    {
                        "first": "H",
                        "middle": [],
                        "last": "Jeffreys",
                        "suffix": ""
                    }
                ],
                "year": 1946,
                "venue": "Proc. Roy. Soc. A",
                "volume": "186",
                "issue": "",
                "pages": "453--461",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "H. Jeffreys. 1946. An invariant form for the prior prob- ability in estimation problems. Proc. Roy. Soc. A, 186:453-461.",
                "links": null
            },
            "BIBREF10": {
                "ref_id": "b10",
                "title": "Sound similarity relations in the mental lexicon: Modeling the lexicon as a complex network",
                "authors": [
                    {
                        "first": "Vsevolod",
                        "middle": [],
                        "last": "Kapatsinski",
                        "suffix": ""
                    }
                ],
                "year": 2006,
                "venue": "",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Vsevolod Kapatsinski. 2006. Sound similarity rela- tions in the mental lexicon: Modeling the lexicon as a complex network. Technical Report 27, Indiana University Speech Research Lab.",
                "links": null
            },
            "BIBREF11": {
                "ref_id": "b11",
                "title": "Phonetic comparison algorithms",
                "authors": [
                    {
                        "first": "Brett",
                        "middle": [],
                        "last": "Kessler",
                        "suffix": ""
                    }
                ],
                "year": 2005,
                "venue": "Transactions of the Philological Society",
                "volume": "103",
                "issue": "2",
                "pages": "243--260",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Brett Kessler. 2005. Phonetic comparison algo- rithms. Transactions of the Philological Society, 103(2):243-260.",
                "links": null
            },
            "BIBREF12": {
                "ref_id": "b12",
                "title": "The \"proportion-of-the-total-duration rule for the discrimination of auditory patterns",
                "authors": [
                    {
                        "first": "R",
                        "middle": [],
                        "last": "Gary",
                        "suffix": ""
                    },
                    {
                        "first": "C",
                        "middle": [
                            "S"
                        ],
                        "last": "Kidd",
                        "suffix": ""
                    },
                    {
                        "first": "",
                        "middle": [],
                        "last": "Watson",
                        "suffix": ""
                    }
                ],
                "year": 1992,
                "venue": "Journal of the Acoustic Society of America",
                "volume": "92",
                "issue": "",
                "pages": "3109--3118",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Gary R. Kidd and C.S. Watson. 1992. The \"proportion-of-the-total-duration rule for the dis- crimination of auditory patterns. Journal of the Acoustic Society of America, 92:3109-3118.",
                "links": null
            },
            "BIBREF13": {
                "ref_id": "b13",
                "title": "Algorithms for Language Reconstruction",
                "authors": [
                    {
                        "first": "Grzegorz",
                        "middle": [],
                        "last": "Kondrak",
                        "suffix": ""
                    }
                ],
                "year": 2002,
                "venue": "",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Grzegorz Kondrak. 2002. Algorithms for Language Reconstruction. Ph.D. thesis, University of Toronto.",
                "links": null
            },
            "BIBREF14": {
                "ref_id": "b14",
                "title": "Binary codes capable of correcting deletions, insertions and reversals",
                "authors": [
                    {
                        "first": "V",
                        "middle": [
                            "I"
                        ],
                        "last": "Levenstein",
                        "suffix": ""
                    }
                ],
                "year": 1965,
                "venue": "Doklady Akademii Nauk SSSR",
                "volume": "163",
                "issue": "4",
                "pages": "845--848",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "V.I. Levenstein. 1965. Binary codes capable of cor- recting deletions, insertions and reversals. Doklady Akademii Nauk SSSR, 163(4):845-848.",
                "links": null
            },
            "BIBREF15": {
                "ref_id": "b15",
                "title": "Recognizing spoken words: The neighborhood activation model",
                "authors": [
                    {
                        "first": "Paul",
                        "middle": [],
                        "last": "Luce",
                        "suffix": ""
                    },
                    {
                        "first": "D",
                        "middle": [],
                        "last": "Pisoni",
                        "suffix": ""
                    }
                ],
                "year": 1998,
                "venue": "Ear and Hearing",
                "volume": "19",
                "issue": "",
                "pages": "1--36",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Paul Luce and D. Pisoni. 1998. Recognizing spoken words: The neighborhood activation model. Ear and Hearing, 19:1-36.",
                "links": null
            },
            "BIBREF16": {
                "ref_id": "b16",
                "title": "Cognitive Models of Speech Perception: Psycholinguistic and Computational Perspectives, chapter Similarity neighborhoods of spoken words",
                "authors": [
                    {
                        "first": "Paul",
                        "middle": [],
                        "last": "Luce",
                        "suffix": ""
                    },
                    {
                        "first": "D",
                        "middle": [],
                        "last": "Pisoni",
                        "suffix": ""
                    },
                    {
                        "first": "S",
                        "middle": [],
                        "last": "Goldinger",
                        "suffix": ""
                    }
                ],
                "year": 1990,
                "venue": "",
                "volume": "",
                "issue": "",
                "pages": "122--147",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Paul Luce, D. Pisoni, and S. Goldinger, 1990. Cog- nitive Models of Speech Perception: Psycholinguis- tic and Computational Perspectives, chapter Simi- larity neighborhoods of spoken words, pages 122- 147. MIT Press, Cambridge, MA.",
                "links": null
            },
            "BIBREF17": {
                "ref_id": "b17",
                "title": "Finding families: quantitative methods in language classification",
                "authors": [
                    {
                        "first": "April",
                        "middle": [],
                        "last": "Mcmahon",
                        "suffix": ""
                    },
                    {
                        "first": "Robert",
                        "middle": [],
                        "last": "Mcmahon",
                        "suffix": ""
                    }
                ],
                "year": 2003,
                "venue": "Transactions of the Philological Society",
                "volume": "101",
                "issue": "",
                "pages": "7--55",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "April McMahon and Robert McMahon. 2003. Find- ing families: quantitative methods in language clas- sification. Transactions of the Philological Society, 101:7-55.",
                "links": null
            },
            "BIBREF18": {
                "ref_id": "b18",
                "title": "Swadesh sublists and the benefits of borrowing: an andean case study",
                "authors": [
                    {
                        "first": "April",
                        "middle": [],
                        "last": "Mcmahon",
                        "suffix": ""
                    },
                    {
                        "first": "Paul",
                        "middle": [],
                        "last": "Heggarty",
                        "suffix": ""
                    },
                    {
                        "first": "Robert",
                        "middle": [],
                        "last": "Mcmahon",
                        "suffix": ""
                    },
                    {
                        "first": "Natalia",
                        "middle": [],
                        "last": "Slaska",
                        "suffix": ""
                    }
                ],
                "year": 2005,
                "venue": "Transactions of the Philological Society",
                "volume": "103",
                "issue": "2",
                "pages": "147--170",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "April McMahon, Paul Heggarty, Robert McMahon, and Natalia Slaska. 2005. Swadesh sublists and the benefits of borrowing: an andean case study. Trans- actions of the Philological Society, 103(2):147-170.",
                "links": null
            },
            "BIBREF19": {
                "ref_id": "b19",
                "title": "Rao distances",
                "authors": [
                    {
                        "first": "A",
                        "middle": [],
                        "last": "Charles",
                        "suffix": ""
                    },
                    {
                        "first": "Lyle",
                        "middle": [],
                        "last": "Micchelli",
                        "suffix": ""
                    },
                    {
                        "first": "",
                        "middle": [],
                        "last": "Noakes",
                        "suffix": ""
                    }
                ],
                "year": 2005,
                "venue": "Journal of Multivariate Analysis",
                "volume": "92",
                "issue": "1",
                "pages": "97--115",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Charles A. Micchelli and Lyle Noakes. 2005. Rao dis- tances. Journal of Multivariate Analysis, 92(1):97- 115.",
                "links": null
            },
            "BIBREF20": {
                "ref_id": "b20",
                "title": "A comparison of phylogenetic reconstruction methods on an ie dataset",
                "authors": [
                    {
                        "first": "Luay",
                        "middle": [],
                        "last": "Nakleh",
                        "suffix": ""
                    },
                    {
                        "first": "Tandy",
                        "middle": [],
                        "last": "Warnow",
                        "suffix": ""
                    },
                    {
                        "first": "Don",
                        "middle": [],
                        "last": "Ringe",
                        "suffix": ""
                    },
                    {
                        "first": "Steven",
                        "middle": [
                            "N"
                        ],
                        "last": "Evans",
                        "suffix": ""
                    }
                ],
                "year": 2005,
                "venue": "Transactions of the Philological Society",
                "volume": "103",
                "issue": "2",
                "pages": "171--192",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Luay Nakleh, Tandy Warnow, Don Ringe, and Steven N. Evans. 2005. A comparison of phylogenetic reconstruction methods on an ie dataset. Transactions of the Philological Society, 103(2):171-192.",
                "links": null
            },
            "BIBREF21": {
                "ref_id": "b21",
                "title": "Measuring dialect distance phonetically",
                "authors": [
                    {
                        "first": "J",
                        "middle": [],
                        "last": "Nerbonne",
                        "suffix": ""
                    },
                    {
                        "first": "W",
                        "middle": [],
                        "last": "Heeringa",
                        "suffix": ""
                    }
                ],
                "year": 1997,
                "venue": "Proceedings of SIGPHON-97: 3rd Meeting of the ACL Special Interest Group in Computational Phonology",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "J. Nerbonne and W. Heeringa. 1997. Measuring dialect distance phonetically. In Proceedings of SIGPHON-97: 3rd Meeting of the ACL Special In- terest Group in Computational Phonology.",
                "links": null
            },
            "BIBREF23": {
                "ref_id": "b23",
                "title": "On the distance between two populations",
                "authors": [
                    {
                        "first": "C",
                        "middle": [
                            "R"
                        ],
                        "last": "Rao",
                        "suffix": ""
                    }
                ],
                "year": 1949,
                "venue": "",
                "volume": "",
                "issue": "",
                "pages": "246--248",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "C.R. Rao. 1949. On the distance between two popula- tions. Sankhy\u0101, 9:246-248.",
                "links": null
            },
            "BIBREF24": {
                "ref_id": "b24",
                "title": "Indoeuropean and computational cladistics",
                "authors": [
                    {
                        "first": "D",
                        "middle": [],
                        "last": "Ringe",
                        "suffix": ""
                    },
                    {
                        "first": "Tandy",
                        "middle": [],
                        "last": "Warnow",
                        "suffix": ""
                    },
                    {
                        "first": "A",
                        "middle": [],
                        "last": "Taylor",
                        "suffix": ""
                    }
                ],
                "year": 2002,
                "venue": "Transactions of the Philological Society",
                "volume": "100",
                "issue": "1",
                "pages": "59--129",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "D. Ringe, Tandy Warnow, and A. Taylor. 2002. Indo- european and computational cladistics. Transac- tions of the Philological Society, 100(1):59-129.",
                "links": null
            },
            "BIBREF25": {
                "ref_id": "b25",
                "title": "Kernel Methods for Pattern Analysis",
                "authors": [
                    {
                        "first": "John",
                        "middle": [],
                        "last": "Shawe",
                        "suffix": ""
                    },
                    {
                        "first": "-",
                        "middle": [],
                        "last": "Taylor",
                        "suffix": ""
                    },
                    {
                        "first": "Nello",
                        "middle": [],
                        "last": "Cristianini",
                        "suffix": ""
                    }
                ],
                "year": 2004,
                "venue": "",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "John Shawe-Taylor and Nello Cristianini. 2004. Ker- nel Methods for Pattern Analysis. Cambridge Uni- versity Press.",
                "links": null
            },
            "BIBREF26": {
                "ref_id": "b26",
                "title": "Toward a universal law of generalization for physical science",
                "authors": [
                    {
                        "first": "R",
                        "middle": [
                            "N"
                        ],
                        "last": "Shepard",
                        "suffix": ""
                    }
                ],
                "year": 1987,
                "venue": "Science",
                "volume": "237",
                "issue": "",
                "pages": "1317--1323",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "R.N. Shepard. 1987. Toward a universal law of gen- eralization for physical science. Science, 237:1317- 1323.",
                "links": null
            },
            "BIBREF27": {
                "ref_id": "b27",
                "title": "Filled pauses and their status in the mental lexicon",
                "authors": [
                    {
                        "first": "Richard",
                        "middle": [
                            "C"
                        ],
                        "last": "Shillcock",
                        "suffix": ""
                    },
                    {
                        "first": "Simon",
                        "middle": [],
                        "last": "Kirby",
                        "suffix": ""
                    },
                    {
                        "first": "Scott",
                        "middle": [],
                        "last": "Mcdonald",
                        "suffix": ""
                    },
                    {
                        "first": "Chris",
                        "middle": [],
                        "last": "Brew",
                        "suffix": ""
                    }
                ],
                "year": 2001,
                "venue": "Proceedings of the 2001 Conference of Disfluency in Spontaneous Speech",
                "volume": "",
                "issue": "",
                "pages": "53--56",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Richard C. Shillcock, Simon Kirby, Scott McDonald, and Chris Brew. 2001. Filled pauses and their status in the mental lexicon. In Proceedings of the 2001 Conference of Disfluency in Spontaneous Speech, pages 53-56.",
                "links": null
            },
            "BIBREF28": {
                "ref_id": "b28",
                "title": "Lexico-statistic dating of prehistoric ethnic contacts",
                "authors": [
                    {
                        "first": "M",
                        "middle": [],
                        "last": "Swadesh",
                        "suffix": ""
                    }
                ],
                "year": 1952,
                "venue": "Proceedings of the American philosophical society",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "M. Swadesh. 1952. Lexico-statistic dating of prehis- toric ethnic contacts. Proceedings of the American philosophical society, 96(4).",
                "links": null
            },
            "BIBREF29": {
                "ref_id": "b29",
                "title": "Exploring the Adaptive Structure of the Mental Lexicon",
                "authors": [
                    {
                        "first": "Monica",
                        "middle": [],
                        "last": "Tamariz",
                        "suffix": ""
                    }
                ],
                "year": 2005,
                "venue": "",
                "volume": "",
                "issue": "",
                "pages": "",
                "other_ids": {},
                "num": null,
                "urls": [],
                "raw_text": "Monica Tamariz. 2005. Exploring the Adaptive Struc- ture of the Mental Lexicon. Ph.D. thesis, University of Edinburgh.",
                "links": null
            }
        },
        "ref_entries": {
            "TABREF0": {
                "num": null,
                "html": null,
                "text": "",
                "type_str": "table",
                "content": "<table><tr><td/><td>one</td><td>two</td><td>three</td><td>four</td><td>five</td></tr><tr><td>one</td><td colspan=\"5\">0.102 0.027 0.023 0.024 0.024</td></tr><tr><td>two</td><td colspan=\"5\">0.028 0.107 0.024 0.026 0.015</td></tr><tr><td colspan=\"6\">three 0.024 0.024 0.107 0.023 0.023</td></tr><tr><td>four</td><td colspan=\"5\">0.025 0.025 0.022 0.104 0.023</td></tr><tr><td>five</td><td colspan=\"5\">0.026 0.015 0.023 0.025 0.111</td></tr></table>"
            },
            "TABREF1": {
                "num": null,
                "html": null,
                "text": "",
                "type_str": "table",
                "content": "<table/>"
            }
        }
    }
}