Sunday, March 1, 2015

Sports Philosophy: Part 1

In the 2013 NFC championship game, the 49ers were driving down the field against the Seahawks, needing a touchdown to win the game and reach the Super Bowl. As they completed short pass after short pass, the anxiety of the home Seattle fans was building, and the FOX broadcasters were growing more and more animated with each play.

Any sane person would tell you that the 49ers chances of winning were increasing as they marched down the field. It makes sense: closer to the end zone=closer to scoring=closer to winning the game. The logic is sound. Completely inarguable. Or is it?

A supposedly insane mathematics genius (or just the win probability calculator on would tell you that the 49ers chances of winning were actually decreasing as they moved down the field. Why? The time. The 49ers were running out of time so fast that 15 yard completions on first down were actually making them more likely to lose.  

The naked eye obviously has a hard time making win probability estimates or calculating the relevance of each play in complex games. It’s hard to tell if a 4-yard run on first down is a good play or if making 1 out of 2 free throws is a good offensive possession. Was the sacrifice bunt a productive play in this situation? How can we know for sure?

You may be asking yourself how this relates to sports betting, or merely to anything at all. Why should we want this information? How can this have any impact on our lives? We want the information so that we can actually know what we’re supposed to root for when we watch sports. And to further the point, this approach helps us make educated decisions if we’re going to make predictions and put our money where our mouths are.

Sports have more mathematics, probability, luck, etc. than just about anyone is willing to believe. But when you finally embrace this philosophy everything becomes clearer. Suddenly the game becomes a simple numbers problem and you have a great understanding of what is actually going on.

If you choose to believe in momentum or clutch genes or whatever else you picked up watching ESPN, you should at least be able to assign some value to it. Asking how much something is worth is absolutely essential to being a knowledgeable sports fan and sports bettor.

I recently had a debate with a friend about a game between the Cavaliers and Knicks in which the Cavs were huge favorites. He argued that the Cavs were a good bet that day because they had All-Stars and the Knicks team was full of scrubs. His analysis was spot on, but his conclusion was baseless. I agreed with him that the Cavs were great and the Knicks were terrible but contested that the difference in talent was worth far less than the 17 point spread implied. The best teams in the NBA outscore their opponents by 7-10 points per game (see standard point differential statistics) and 17-point win margins are only fair to assume in extreme cases.

Subjective reasoning can be useful at times, but only if you’re able to estimate its importance. You cannot simply pick against a team because their best player is injured and expect to be right. The value of that player needs to be properly accounted for and then compared to the game’s odds. This is where most people falter and why most sports predictions fail. They are founded on emotions and subjectivity and not data and facts. Our minds are always getting in the way when we think about sports, a point that I will expand on when this (let’s call it a lecture) continues.

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