If you’ve spent the last week or so fretting about whether the Nats win “Home Field Advantage” you may want to re-think it. A quick analysis of the past 21 years of National League Division Series indicates that Home Field Advantage is a bit of a myth.
There have been three constants in the sports media as the playoffs approach. First, home field advantage is huge. Second, the home field advantage is multiplied when it involves a West Coast team as the home team. Third, it’s important for the team to enter the playoffs on a hot streak. The data does not support any of these hypotheses.
Here’s a quick glimpse of the NLDS playoffs since 1995.
The Home Team has won 21 of the 42 series. That’s exactly equivalent to a coin flip.
West Coast Home Teams are a dismal 2-6 in these series. Flying to the West Coast to open the series apparently had no ill effects in 75% of the cases. Three of those home losses were to true East Coast teams. Logically one would think that the flight out, the jet lag, etc would have a big impact. The data does not support that.
The most significant statistical correlation in this data set is the outcome of the first game. If the Visiting Team wins the first game their odds of winning the series are 90%. The Visitors have won the first game 19 times. Only one of those teams went on to lose the series. On the other hand, only two Visitors lost the first game and then went on to win the series. Excluding the abomination in 2012 when the Nationals, as the Home Team played the first game on the road, the winner of the first game went on to win the series 92.7% of the time.
As for being hot coming into the playoffs you need look no farther than 2014. The Nationals came into the NLDS having won 16 of their last 21 games with the final game being the emotional Jordan Zimmermann No-Hitter. The Giants entered the series having gone 11-10 over their last 21 games. They also had used their best pitcher in the Wild Card Game. But, they came into town, won the first game, and we all know the rest. There are many similar examples in the data. The playoffs are, truly, a new season.
So, are you still fretting about the so-called “Home Field Advantage?” You can stop now. Save your worry beads for the first game of the series. It will likely tell the tale.