How are these numbers calculated?

Big Games

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

Week of 4/13100.0*Average seed
Stevenage 0 Yeovil 2 +0.1
Carlisle 1 Preston 1 -0.1
Shrewsbury 0 Bournemouth 3 +0.1
Crewe 1 Doncaster 2 +0.1
Notts County 3 Colchester 1 -0.1
Swindon 4 Crewe 1 +0.0
Week of 4/20100.0*Average seed
Preston 1 Tranmere 0 +0.5
Crawley Town 1 Preston 0 -0.4
Crewe 1 Sheff Utd 0 -0.2
Bournemouth 3 Carlisle 1 +0.1
Yeovil 1 Crewe 0 +0.1
Swindon 3 Stevenage 0 +0.1
Colchester 0 Shrewsbury 0 +0.0
Week of 4/27100.0*Average seed
Carlisle 0 Colchester 2 +0.4
Sheff Utd 0 Preston 0 -0.2
Crewe 2 Walsall 0 -0.1
Points
Chance Will Win Championship