How are these numbers calculated?

Big Games

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

Week of 12/4100.0*Average seed
Corinthians 3 Vasco da Gama 1 +0.5
Juventude 1 Botafogo 0 -0.2
Guarani 2 Figueirense 1 +0.1
Fluminense 1 Ponte Preta 0 +0.0
Week of 12/11100.0*Average seed
Botafogo 1 Corinthians 2 +0.4
Coritiba 1 Goias 0 +0.2
Figueirense 1 Juventude 0 +0.2
Week of 12/19100.0*Average seed
Corinthians 5 Figueirense 2 +0.5
Goias 2 Sao Paulo 0 -0.4
Juventude 1 Paysandu 2 +0.4
Points
Chance Will Win Championship