How are these numbers calculated?

Big Games

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

Week of 4/10100.0*Chance in playoffs100.0*Average seed
Pirates 247 Rays 191 -22.4
-1.6
White Sox 200 Americans 164 +0.8
+0.1
Red Sox 361 Indians 260 +0.6
+0.0
Blue Jays 271 Brewers 305 +0.4
+0.0
Nationals 169 Twins 250 +0.4
Week of 4/17100.0*Chance in playoffs100.0*Average seed
Rays 194 Red Sox 226 -21.3
-1.0
Twins 232 Pirates 218 +1.5
-0.1
Brewers 298 White Sox 277 -0.6
+0.0
Phillies 225 Blue Jays 294 -0.1
-0.1
Americans 217 Tigers 230 +0.1
+0.0
Indians 192 Nationals 281 +0.0
Week of 4/24100.0*Chance in playoffs100.0*Average seed
Rays 179 Nationals 289 -1.8
Indians 266 Twins 250 +0.3
Brewers 257 Americans 351 -0.2
Phillies 202 White Sox 258 -0.1
Red Sox 236 Pirates 187 -0.0
Blue Jays 251 Tigers 123 -0.0
Games Above .500
Chance Will Make Playoffs