With only 100 wallets and such an informal study i'd be reallly careful about interpretting those stats as saying anything meaningfull, ESPECIALLY about race. There are so many other factors youd want to look at like accounting for income, relation of gender and race between the person finding the wallet and the id of the person in the wallet, etc. There are probably a million ways to get very different results. For example, i wonder how much the results would have changed if the photo id of the person in the wallet was a pretty woman.. Do all the numbers suddenly flip? What if the photo id was of a young kid or an elderly black woman? But it is quite fascinating.