How are these numbers calculated?

Big Games

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

Week of 4/23100.0*Chance in playoffs100.0*Average seed
Palestino 0 River Plate 2 In
+0.5
Alianza Lima 0 Internacional 1 -0.2
Week of 5/7None
Points
Chance Will Make Playoffs