How are these numbers calculated?

Big Games

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

Week of 3/20100.0*Chance in playoffs100.0*Average seed
Volta Redonda 0 Botafogo 1 +13.1
+0.4
Vasco da Gama 2 Americano 3 +10.2
+0.2
America 3 Boavista 2 -7.2
-0.2
Olaria 1 Vasco da Gama 0 +4.6
+0.2
Americano 2 Macae 1 +4.5
+0.1
Bangu 1 America 1 +2.1
+0.1
Botafogo 2 Flamengo 2 +1.8
+0.0
Macae 3 Olaria 1 -1.6
-0.1
Flamengo 3 Tigres do Brasil 1 +0.7
+0.0
Tigres do Brasil 3 Volta Redonda 0 -0.4
Week of 3/27100.0*Chance in playoffs100.0*Average seed
Boavista 1 Botafogo 4 In
+0.3
Vasco da Gama 3 Fluminense 0 -4.6
-0.1
Flamengo 2 America 1 +0.8
+0.1
Macae 2 Duque de Caxias 2 +0.8
Week of 4/3None
Points
Chance Will Make Playoffs