Basketball

This is only the ninth time a 2 has been beaten by a 15. So that doesn't happen every year.
12s have beaten the 5 seed 50 out of 140 tries
13 has beaten the 4 20 out of 140 games
and the 1 has been defeated once by a 16, so far.

Without in depth team knowledge, as in having watched games. Not necessarily an expert. All chalk (higher seed over lower seed) is the way to go. For me 7,8,9, and 10s have been the toughest games to pick.

Never for money just bragging rights.

Edit: these stats go back to '85 when the field was expanded to 64 teams.