Two guys are watching Premier League highlights, when onto the TV screen comes Rory Delap, then with Stoke City, doing one of his renowned throw-ins from the touchline directly into the box. One guy, a native of the American Midwest who’d been raised on baseball, basketball, and hockey, is amazed by the throw and the havoc it creates in front of the opponent’s goal.  “Why don’t other teams do that?” he asks.

The other guy, who grew up with soccer in Germany, explains that Delap is an unusual player, having been trained as a javelin thrower.

“But can’t teams train a guy to make throws like that?” asks the first guy.

“It’s not what you do unless you have to,” answers the second guy, who had played semi-pro soccer in his younger days.

“Well, why not? It seems to work for them.”

The former footballer is stymied for an answer.  All he can say is: “Because.”

In most cases, a debate like this would have ended here, with the guy with superior sports credentials having the final word.  But these guys were Ivy League professors, who do research in behavioral social sciences.  Instead of accepting “because” as an explanation for soccer customs, they began to question the behavior of clubs, managers, and even players, and to research the real outcomes of their decisions.

In their book The Numbers Game: Why Everything You Know About Soccer Is Wrong (Penguin, 2013), these two guys, Chris Anderson and David Sally, offer the results of their investigations.  Using the wealth of data that is now available about what happens on the field, and drawing from current theories in the social sciences, they undermine many of the conventions of on-field strategy and club management.  Their book brings together colorful stories and telling statistics in an engaging and insightful dissection of contemporary soccer.  You’ll be surprised to learn that much of what you knew about soccer is indeed wrong.  And as Chris and Dave admit in the interview, so were they.