How are these numbers calculated?

Big Games

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

Week of 10/20100.0*Average seed
Detroit 45 Ohio 58 +0.5
Los Angeles 45 Boston 52 -0.1
St. Louis 45 Evansville 38 -0.1
New York 19 Tampa Bay 21 -0.1
Week of 10/26100.0*Average seed
D.C. 52 Ohio 59 +0.6
Evansville 44 Detroit 24 -0.1
London 55 Tampa Bay 57 -0.1
Week of 11/2100.0*Average seed
Tampa Bay 52 Ohio 38 -0.5
St. Louis 45 Kansas City 41 -0.2
Boston 40 D.C. 35 -0.2
Evansville 41 London 36 -0.1
Games Above .500
Chance Will Make Playoffs