How are these numbers calculated?

Big Games

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

Week of 5/11100.0*Average seed
Genoa 0 Lazio 2 -0.5
Napoli 3 AC Milan 1 -0.2
Palermo 0 Sampdoria 2 +0.1
AS Roma 2 Atalanta BC 1 +0.0
Week of 5/17100.0*Average seed
Atalanta BC 2 Genoa 0 -0.2
Lazio 2 Napoli 1 +0.1
AC Siena 2 Palermo 2 +0.1
Points
Chance Will Win Championship