How are these numbers calculated?

Big Games

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

Week of 8/9100.0*Chance in playoffs100.0*Average seed
Melb Ice 4 Adelaide 2 -18.3
-0.4
Melb Ice 3 Adelaide 1 -15.0
-0.3
Syd Bears 0 Syd Ice Dogs 8 -10.0
-0.1
Syd Ice Dogs 2 Perth 8 +8.9
+0.1
CBR 4 Melb Mustangs 2 -1.8
Newcastle 6 Syd Bears 2 -0.9
-0.1
CBR 2 Melb Mustangs 4 +0.5
Newcastle 5 Perth 4 -0.4
Week of 8/16100.0*Chance in playoffs100.0*Average seed
Perth 3 Syd Ice Dogs 6 Out
-0.2
Adelaide 5 CBR 2 +12.9
+0.3
Adelaide 6 CBR 2 +12.7
+0.2
Perth 1 Syd Ice Dogs 3 -11.2
-0.1
Melb Mustangs 6 Newcastle 3 +2.4
+0.2
Melb Ice 7 Newcastle 2 +0.1
Week of 8/23None
Points
Chance Will Make Playoffs