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Why Sports Need Randomness

Noah Davis talks to David Sally, one of the authors of The Numbers Game: Why Everything You Know About Soccer Is Wrong, about how uncertainty affects and enhances the games we watch.
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Steven Gerrard. (Photo: Associated Press)

Steven Gerrard. (Photo: Associated Press)

In sports, the best team doesn't always win. Why? Well, sometimes weird stuff happens, things you wouldn't expect and couldn't explain. This randomness, as the saying goes, is why they play the games. According to David Sally and Chris Anderson, authors of The Numbers Game: Why Everything You Know About Soccer Is Wrong, the world's most popular sport is also the most random. Roughly 50 percent of any given contest’s outcome is dictated by randomness. We talked to Sally about what this means for fans, why "coincidence is logical," and a certain league-altering slip.

What is randomness in sports?

There are a number of ways to define randomness, but the simplest way is to think about doing a statistical prediction of a sporting event or an action within sports. I can take a number of factors that I can count, and I can do a regression, and what's left over is randomness or noise. They are the things we can't really predict.

Take goals in soccer. I can explain a lot of goals with statistics and numbers of shots. I won't have much noise. But if I'm trying to predict whether a given shot goes in or how many shots a team generates in a given match, that gets very noisy very quickly. That becomes a very difficult thing to predict on a match-to-match basis. That's a very statistical way to think about randomness.

"When you think about fans, I don't know if I want to rationalize it. You kind of want the tragedy and the comedy that's provided by randomness. You kind of want to tear your hair out when that defender trips over his foot in a random incident."

From a sports fan's perspective, there are events that can happen that you have never seen before. That's one of my favorite experiences. It's not that there is zero probability of that event happening; it's that you don't even place a probability on it happening because you never thought that thing could happen. The shot going in off the beach ball in the Liverpool match. Who would have ever guessed? It can be bad luck, too, like Paul George getting his foot stuck on the stanchion and breaking his leg.

How much of the statistical side of randomness is not having the tools to measure events? Have we reached maximum knowable information in sports?

We know from dynamic systems and Chaos Theory that there are some things that aren't predictable. There's the famous example of a butterfly flapping his wings and creating a hurricane. In a complex, dynamic system that can happen. That's fundamentally not predictable with our current level of science and mathematics.

However, in sports, and especially in soccer, we are very far from that threshold. When it comes to soccer, there are many things that we don't have the inputs for. We know we can do a lot better in terms of what's possible to feed into the equation. Think of a sport like baseball. Now that we have more of the location data, it has more and more inputs even on the defensive side. They are able to improve their predictive ability. But even in baseball, they are still pretty far from the threshold.

Does randomness make sports fun to watch? A lot of the great upsets happen because of what might be conceived of as a series of random occurrences.

I think it's critical to sports. It's essential to the actual consumption. If you knew 100 percent that the Spurs were going to beat the Heat, would it still be worth watching? You want to say that it's a beautiful performance, that I want to watch the Spurs run their offense even though I know the outcome. There's something to the consumption of seeing a talented team play that well. In technical terms, is randomness necessary and sufficient? I think it's actually neither. It's not entertaining to watch somebody roll dice, which is utterly unpredictable.

But I think randomness is an important element. I think there are deep roots in human nature after the consumption, after watching the match, to try to create a narrative around the uncertainty. We have a deep-seated need to create narratives for things that aren't really explainable. Why did lightning strike that guy? That's a completely probabilistic, random event. But we have a need to create narrative. We have a need to sit in the pub after and figure out why it was a “just result,” why “the right team won” and why was that. It's not an interesting narrative to say, “Well, it's just random,” so we discount that.

Not knowing the outcome is a big part of watching sports.

How should fans deal with randomness in sports?

In our book, we quote Johan Cruyff who said "toeval is logisch," which translates to "coincidence is logical." That quote represented his ability as a player to accept the fact that as great as he was and as great as Ajax was, things were going go happen that they couldn't control, like losing to an inferior opponent. At the same time, he could compartmentalize it in some ways. He wasn't going to be tortured by it. It was logical when a random event happened.

On the other hand, when you think about fans, I don't know if I want to rationalize it. You kind of want the tragedy and the comedy that's provided by randomness. You kind of want to tear your hair out when that defender trips over his foot in a random incident. I don't know if we as fans would want to compartmentalize it as clearly as Cruyff does.

I don't think the Liverpool fans who watched Steven Gerrard slip would agree with you, but I see your overall point.

Well, they might want to do away with it. But that's the thing with randomness: you get the negative with the positive.

Can teams take advantage of randomness?

There are some basic principles. If you're the inferior team, you want to get to penalty kicks. You want games and seasons shorter. Under Tony Pulis, Stoke City matches had the ball in play for the shortest amount of time, something like 57 minutes out of the 90 total. They were far better off with less action, less events, less moments for skill. If you're the better team, you want to reduced the amount of noise and luck involved.

In European football, where they play an entire season and don't have playoffs, the best team usually wins. In March Madness, where it’s one loss and you're out, the best team frequently doesn't win.

Soccer's the most random sport but what should fans watch if they don't want randomness?

Triathlons. Long ones, like the Ironman.