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
Pinckney 19 Hartland 11 -2.1
-0.3
South Lyon East 11.5 Howell 18.5 -1.0
South Lyon 12.5 Hartland 17.5 +0.2
Milford 5 Brighton 25 -0.0
Milford 2 Pinckney 28 -0.0
Week of 2/4100.0*Chance wins title100.0*Average seed
Hartland 10 South Lyon 20 -0.1
-0.4
Howell 28 South Lyon 2 No
+0.0
Hartland 27 South Lyon East 3 +0.2
South Lyon East 6 Brighton 24 -0.0
Pinckney 24 Milford 6 -0.0
Week of 2/10100.0*Chance wins title100.0*Average seed
Brighton 14 Hartland 16 +0.5
Pinckney 17 Brighton 13 -0.2
Pinckney 23 South Lyon 7 -0.2
Hartland 6 Howell 24 -0.1
South Lyon East 2 Pinckney 28 -0.1
Games Above .500
Chance Will Win Championship