How are these numbers calculated?

Big Games

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

Week of 2/22100.0*Average seed
Celtic 3 Kilmarnock 1 +0.2
St Johnstone 2 Rangers 2 -0.1
Aberdeen 1 Ross County 2 -0.1
Week of 3/3100.0*Average seed
Motherwell 4 Ross County 1 +0.1
Kilmarnock 2 Aberdeen 2 +0.0
St Mirren 0 St Johnstone 0 -0.0
Week of 3/7100.0*Average seed
St Johnstone 1 Livingston 0 +0.3
Hamilton Accies 1 Kilmarnock 0 +0.3
Points
Chance Will Win Championship