updating irmas info

README.md

@@ -32,7 +32,7 @@ OpenPIR is a hand-labeled dataset for **predominant instrument recognition (PIR)
 
 ## Dataset Summary
 
-[IRMAS](https://www.upf.edu/web/mtg/irmas) is the standard training dataset for predominant instrument recognition, but it has two well-known limitations: relatively small size (6,705 clips), and studio-recorded solo performances that do not reflect the overlapping timbres of real-world music. OpenPIR addresses both by adding 1,228 annotated clips from OpenMic-2018 that are compatible with IRMAS labels — supplementing every instrument category and introducing genuine multi-label annotations.
+[IRMAS](https://www.upf.edu/web/mtg/irmas) is the standard training dataset for predominant instrument recognition, but it has two well-known limitations: relatively small size (6,705 clips), and training examples with only one predomiant instrument label (even if more than one is present) that do not reflect the overlapping timbres of real-world music and the test set ( which may have 1-5 predominant labels per clip). OpenPIR addresses both by adding 1,228 annotated clips from OpenMic-2018 that are compatible with IRMAS labels — supplementing every instrument category and introducing genuine multi-label annotations.
 
 ## Dataset Construction