How are these numbers calculated?

Big Games

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

Week of 11/11100.0*Chance wins title
Atletico-GO 5 Tupi 3 Yes
Luverdense 2 Bahia 2 +0.6
Avai 3 Nautico 0 -0.3
Bragantino 1 Vasco da Gama 2 -0.2
Week of 11/18None
Week of 11/25None
Chance Will Win Championship