How are these numbers calculated?

Big Games

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

Week of 5/28100.0*Chance in playoffs100.0*Average seed
Chile 18 Portugal 6 -16.4
-0.5
Portugal 26 Namibia 17 +0.9
+0.5
Chile 6 Italy 50 +0.5
Italy 33 Namibia 7 -0.2
-0.0
Week of 6/5100.0*Chance in playoffs100.0*Average seed
Italy 59 Portugal 13 No
-0.1
Chile 23 Namibia 21 -0.0
Games Above .500
Chance Will Make Playoffs