How are these numbers calculated?

Big Games

How we did last week and who we should root for this week.   Explain

Week of 11/6100.0*Chance in playoffs100.0*Average seed
Witcraft 10 Schoolman 6 -22.6
-0.8
Hartman 10 Kato 3 +0.7
Zwiefel 9 M. Jackson 4 -0.7
K. Jackson 5 Scheck 8 -0.4
-0.0
Week of 11/20100.0*Chance in playoffs100.0*Average seed
Zwiefel 7 Schoolman 11 +13.4
+1.3
Witcraft 11 Kato 5 -13.4
-0.1
Chick 7 Scheck 6 -0.6
Games Above .500
Chance Will Make Playoffs