In 2008, the Phillies went 92-70, finishing 3 games ahead of the Mets in the NL East and ultimately winning the World Series. What can we expect this year, the year after the world championship?
Of course, one way to answer this question is to use a complex system like PECOTA or Marcel's Monkey to predict each team's performance for the year. I'll leave that to others.
Another way to approach the problem, with admittedly much less predictive value but nonetheless with some informative content, is to look at recent trends of the World Series champions. And those trends don't bode well for the Phillies.
Over this decade, taking away the Phillies, there have been 8 World Series won by 7 different teams. Only the Red Sox have won twice. The point of this study though is that no team won the World Series two years in a row. And, six of the eight teams that won the World Series lost more games the year after the World Series year. Only one reached the World Series the year after.
On average, the World Series champion lost 4.25 games more the year following the World Series.
This chart summarizes the performances of the World Series winners this decade:
|Year||WS Winner||WS Year Record||Next Year Record||Change||Postseason|
|2000||Yankees||87-74||95-65||+8||lost in World Series|
|2001||Diamondbacks||92-70||98-64||+6||lost in NLDS|
|2004||Red Sox||98-64||95-67||-3||lost in ALDS|
|2007||Red Sox||96-66||95-67||-1||lost in ALCS|
What does this chart prove for the Phillies this coming year? Like I said above, there is no exact predictive value here.
But, what it does show is that regression to the mean is a very powerful thing. Just like it can be the powerful force behind the Sports Illustrated cover jinx, it can also be the reason that World Series teams struggle to keep up the level of excellence the year following the championship. Thus, not only will the Phillies be battling against the re-vamped Mets and Braves this year, but also against a basic mathematical principle.