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 +0.5
South Lyon East 11.5 Howell 18.5 No
+0.0
Milford 5 Brighton 25 -0.0
Milford 2 Pinckney 28 +0.1
South Lyon 12.5 Hartland 17.5 -0.0
Week of 2/4100.0*Chance wins title100.0*Average seed
Hartland 10 South Lyon 20 +0.1
Pinckney 24 Milford 6 +0.1
Hartland 27 South Lyon East 3 -0.1
Howell 28 South Lyon 2 +0.0
Week of 2/10100.0*Chance wins title100.0*Average seed
Pinckney 17 Brighton 13 +0.8
Pinckney 23 South Lyon 7 +0.3
South Lyon East 2 Pinckney 28 +0.2
Hartland 6 Howell 24 +0.1
Brighton 14 Hartland 16 -0.1
Brighton 3 Howell 27 +0.1
Games Above .500
Chance Will Win Championship