As It Happens

Cheat sheet tells you when it's safe to leave the ballpark early — if you're one of those people

Statistician Kaiser Fung has looked at the data and figured out the best time to leave a baseball game early — with little risk of missing the action.

Kaiser Fung's cheat sheet isn't catered to die-hard fans, but those who don't mind leaving early

Toronto Blue Jays fans cheer ahead of game three American League Championship Series baseball action between the Blue Jays at Cleveland Indians in Toronto on Oct. 17, 2016. (Mark Blinch/Canadian Press)

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The game has been going on for hours, the outcome seems decided, and the thought of beating the crowds to the parking lot is appealing. You pack up your peanuts and start to head home — even though the baseball game isn't officially done.

For some fans of the sport, leaving a game before it's over may sound like sacrilege.

But for those who aren't opposed, New York statistician Kaiser Fung and his colleagues have developed a cheat sheet that could help people decide the right time to leave — when there's a low probability the game will turn around.

They published their findings on the website FiveThirtyEight.

Fung spoke with As It Happens guest host and Toronto Blue Jays fan Piya Chattopadhyay. Here's a part of their conversation: 

Are you the guy who bails because you want to get to the car and get out of there — or are you the guy who sticks around?

I kind of solved this problem for myself, in a way. I'm the person who, if I have better things to spend my time on … I might leave early.

But on the other hand, if it is like a World Series game, it's a very important game, it's an exciting game, I'll be there.

Let's say the Toronto Blue Jays are leading by four runs … at what point am I safe to leave the stadium, knowing that my team likely will not get creamed?

What happens is if you have a four-run lead, it obviously would depend on what inning you are in.

If you are deep into the game, your four runs would be, you know, quite safe. If it's early in the game, maybe the other team might still come back.

What we have done in the cheat sheet is to tell you exactly when it is safe to leave.

In this particular case, if it is four runs, then after the fifth or after the sixth you should leave without too much fear of missing out on anything exciting.  

A four-run spread in baseball is not unusual, but we often have games [where] you're two runs up. ... What if they're ahead by just two runs — I shouldn't leave?

You pretty much have to keep staying. However, if there's a two-run lead at the end of the eighth inning, you could leave an inning early. That would be in OK.

In our world, what that means is that there's … on average a five per cent chance that you might miss out on something. But 95 per cent of the time, the lead is not going to be lost

How did you work this out?

We actually took five seasons, 2010 through 2015, every single game.

For every inning, we worked out what's the run differential at the end of the inning, and who's the eventual winner, and we compiled all of that information.

We used the 2016 season as a validation. We didn't use it to create the cheat sheet, but we applied it to the 2016 season to see what happens. The accuracy rate is about 97 per cent.

We did point out ... that it's not like every game will be correctly predicted.  About 60 games … out of the total of over 17,000, would be where you have left and then there was a lead change afterwards.  

We've been looking at some of your feedback on Twitter … Here's what [a Chicago Cubs fan] tweeted at you:

"As a life long Cubs fan the premise of the piece breaks my brain ... going to games is about SHOWING support for your team. For better or for worse. In good times and in bad. The IMPROBABLE wins are the ones I've never forgotten."

Does [he] have a point here?

Like I said, it's your personal decision.

For a lot of people, it's a tradeoff between the amount of time that you can save … versus the potential for missing out on something unlikely.

The key point here is that I'm not starting any trends. … It's already happening. It's just that we can apply some data analysis and get a more accurate way of determining when to leave, which would be useful for the people who are planning on leaving.

Do you have a message for Major League Baseball in all of this?

I think the league office has already been pushing for a number of years to try to shorten the games.

Some of the measures are really to increase the amount of action time versus non-action time, which I think is a very commendable thing to do.

Kaiser Fung is a statistician based in New York. (Provided by Kaiser Fung)

I have like one sort of out-of-the-box idea.

It's possible, if you follow the kind of math that we're doing here … to consider possibly calling a game early.

You're not really advocating for that are you?

I'm not advocating that but … I think if there's a lot of action, people are going to stick around.

It's really, you know, the staring and the walking around and the waiting and the stalling that's making people want to leave.

Written by Katie Geleff. Produced by Jeanne Armstrong. This Q&A has been edited for length and clarity. 


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