Listening to game three of the National League Divisional Series between the Washington Nationals and Los Angeles Dodgers today on the way to the airport, I heard a startingly weighty statistic: The team that wins game three of a five-game series wins 77% of series! That’s one pivotal game!
After mulling over that for a second, I thought to myself, “Hmm, I wonder if that’s significantly different from what you’d expect even with each game being a coin flip. After all, it’s not like the winner of any game in a series is only 50% to win the whole best-of-five.” And with Gogo internet on the flight in typical fine form, I had plenty of extra time to jump into a quick Julia REPL and find out.
We can simulate a 5-game series between teams
In real life they don’t play games 4 and 5, but there’s less effort making the machine calculate those dead rubber games than real major league playoff games.
Here’s a function to see whether the winner of game three won the series:
So now let’s just run that simulation 100,000 times and see what happens.
So even if every game were a simple coin flip, the team that won game three would win about 69% of series. And of course, the games aren’t exactly coin flips — one of the teams is probably a little bit better than the other, skewing that number even higher.
A nice thought experiment realized while flying without internet. What I failed to figure out is how my laptop could chat with a ground-based customer service rep to troubleshoot the broken airborne Wi-Fi.