How are these numbers calculated?

Big Games

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

Week of 1/28100.0*Chance wins title100.0*Average seed
Hartland 4 Brighton 26 -4.9
-0.2
Howell 26 Brighton 4 -1.7
Hartland 15.5 South Lyon East 15 +1.2
+0.1
Howell 29 South Lyon East 1 -0.8
-0.0
Week of 2/5100.0*Chance wins title100.0*Average seed
Hartland 15 South Lyon 16 -0.7
-0.4
Milford 0 Howell 30 -0.1
Brighton 4.5 Howell 25.5 No
+0.0
Pinckney 2 Hartland 28 +0.2
South Lyon East 4 Hartland 26 +0.3
Brighton 22 South Lyon 8 -0.2
Week of 2/10100.0*Chance wins title100.0*Average seed
Brighton 18 Pinckney 12 -0.2
Hartland 8 Howell 22 -0.1
South Lyon 15 Howell 16 +0.1
Milford 5 Brighton 25 -0.0
South Lyon 27 South Lyon East 3 -0.0
Hartland 19 Milford 11 +0.0
Games Above .500
Chance Will Win Championship