How are these numbers calculated?

Big Games

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

Week of 1/27100.0*Chance wins title100.0*Average seed
South Lyon East 11.5 Howell 18.5 +8.5
+0.1
Pinckney 19 Hartland 11 +5.5
+0.1
South Lyon 12.5 Hartland 17.5 -2.1
Brighton 24 South Lyon East 6 -1.2
Milford 5 Brighton 25 -1.0
Week of 2/4100.0*Chance wins title100.0*Average seed
Howell 28 South Lyon 2 +5.1
+0.1
Hartland 10 South Lyon 20 +3.4
South Lyon East 6 Brighton 24 -1.9
Hartland 27 South Lyon East 3 -1.2
Week of 2/10100.0*Chance wins title100.0*Average seed
Pinckney 17 Brighton 13 Yes
Games Above .500
Chance Will Win Championship