the data here is useful for testing classification / clustering, and the accuracy of indexing techniques. However the datasets are too small to make claims about the efficiency of indexing.
Chaim Zins' R&D projects. Map of Human Knowledge. Portal to Human Knowledge . The Encyclopedic Portal, a systematic portal to the Wikipedia encyclopedia.
There are many different folk tales in the world, but many tales are variations on a limited number of themes. The classification system originally designed by Aarne, and later revised first by Thompson and later by Uther, is intended to bring out the similarities between tales by grouping variants of the same tale under the same ATU category. like hraf