The Fine Line Between Luck and Skills in Sports
Hitting a home run in Major League Baseball is as easy as … well, something extremely difficult to accomplish. Most of those who are reading this article would do just as poorly as the author when attempting this feat. As someone who thought T-ball looked challenging, I shouldn’t be the one to criticize the skills of professional ballplayers. But within any sport, fans of the losing team often crave to attribute certain events (such as home runs) to mere luck, a variable nearly impossible to quantify. As the predictive power of statistics becomes ever-present in athletics, the gray area between luck and skill prohibits sabermetrics’ effectiveness.
This past weekend data analysts, economists, and television personalities addressed this conundrum at the MIT Sloan Sports Analytics Conference in Boston. Notable speakers Nate Silver, Michael Maubausin, and others lead two talks about the predictive ability of sports and its correlation to luck. In one presentation, a number of activities were arranged on a line, a continuum of luck and skill. Roulette was placed deep into the “luck” side, while chess sat opposite, in the territory of “skill.” Hockey was located at dead middle (sorry NHL fans), followed in increasing order of skill by baseball, football, soccer and finally, basketball.
As a lifelong Mariners fan (who has suffered 11 long years of losing seasons), the idea that luck decided the M’s unfavorable fate felt reassuring, and my thoughts began racing. I knew we weren’t bad, just unlucky. Then the voice of reason chimed in. No, we are bad; “unlucky” is just a bunch of malarkey. So what was I left to believe about my beloved, crappy Mariners?
The speakers wasted no time in explaining how highly evolved professional sports have become in the past century. Back in the day of the great Ted Williams, batting over .400 was four standard deviations away from the league’s mean. Now, if you haven’t taken Professor McConville’s introductory statistics course, hopefully you take my word when I promise you that most batting averages two standard deviations away from the mean would be significant. Two standard deviations above, you’re doing significantly well; two standard deviations below, you might be worried about your spot in the lineup. Today, professional ballplayers, especially pitchers, are overall much more skilled than they were in 1941. The league’s average batting average nowadays is 0.254. If someone, say Mike Trout, were to hit over 0.400 (the same as Ted Williams), that would be five standard deviations away from our current norm. Of course, these days, the size of each standard deviation is much smaller than what it was seventy-two years ago, because the skills of major leaguers are roughly the same.
Essentially, the line that separates skill and luck is so blurred because the divide between the talented from the rest of the pack is so narrow. The distinction is in fact so slight that some sports have had to create new scoring systems in order to create separation. For example, gymnastics, which once ran on a 10-point scale, now reports scores in the mid-teens, to allow for greater variance in the complexity of routines. Additionally, the Olympic male marathoners have become so fast that a mere seven minutes separates the gold medalist from the 20th place finisher, whereas only decades ago, this number would be around half an hour. Again, runners have become so advanced that the clock must reach more decimal places in order to separate their times.
So how does any of this sound lucky? Really, it’s not. Athletes today are stronger, faster, smarter, and more skilled than former players. Luck’s presence in sports such as baseball is magnified only because standard deviations in performance (quantified in ways such as batting average) are so miniscule. When data analysts attempt to predict performance utilizing statistics with such narrow margins, the result is can be too close to accurately call, especially when the possibility of a “bad break” or a stroke of “dumb luck” is possible.
If a baseball game was nothing more then rolling a pair of dice, wouldn’t we all be swinging at pitches, earning millions of dollars? As luck would have it, only the truly gifted make it to the pros. Over time, players will become even more skilled, while the role of luck, and its effects on a game’s outcome will challenge our predictive abilities.