Checking in on the MDS Model's Performance ATS

It's important to check one's work, and although the MDS Model's performance against the spread has been very good thus far (it would have ranked #1 in NBA for the 2013-2014 season, ranks 1st currently in NBA (56.40%), and ranks 1st currently in NCAAB (53.18%)), I needed to establish a concrete statistical test to determine if I'm just getting lucky, or if I'm actually achieving good results.

I installed an automatic z-score test for each sport with spreads (NBA, NCAAB, NFL, NCAAF). I just want to be fairly sure I'm actually picking winners better than 50% of the time, so I'm willing to accept findings at a p-value of 0.9 or better. The following results are in:

• NBA: Win % (all-time): 54.85%, Games Picked: 608, z-score: 2.40, p-value: 0.992
• NCAAB: Win % (all-time): 53.23%, Games Picked: 980, z-score: 2.02, p-value: 0.979
• NFL: Win % (all-time): 54.70%, Games Picked: 293, z-score: 1.61, p-value: 0.947
• NCAAF: Win % (all-time): 51.67%, Games Picked: 1156, z-score: 1.14, p-value: 0.872

Ironically enough, the one sport I can't conclude that I'm doing better than 50/50 by chance (with 90% confidence or better) is college football, the original sport I built MDS for.