2012 and 2013 gave us two of the most compelling MVP races in recent memory. Both boiled down to Mike Trout versus Miguel Cabrera, but in the public eye, it was more than that. The MVP race became a referendum on sabermetrics. Statheads versus scouts. New school versus old school.
Trout had WAR, Miggy had the narrative. Trout was a better all-around player, Miggy was the better pure hitter. Both put up otherworldly numbers, but Cabrera had one advantage: His Tigers went 181-143 and won two division titles, while Trout's Angels went 167-157 with no playoff appearances. In the end, Miggy took the award both years, with 92%-67% and 92%-72% share percentages, which are pretty large differences.
Now, the postseason appearances probably weren't the only reason why Cabrera took home the award, but they didn't hurt his case. The question becomes, then, how much do playoff appearances help an MVP candidate's case, and should they help?
So let's start by getting data. We're looking at the batters who finished in the top 10 of the MVP vote since 1989. Why only batters? Including pitchers complicates matters a bit, and I want to keep this as simple as possible. Further, we'll wind out looking at the following stats: bWAR, SB, and the three Triple Crown stats (HR, RBI, and AVG). All values were standardized to make coefficients a bit more comparable.
Lets start with just some exploratory analyses. If you take a look at the 452 player-seasons in the dataset, 248 of them were on playoff teams, for a total of 54.9%. That's not an overly impressive difference, but let's dig a little further.
The average rank for a player on a playoff team? 4.77. For a non-playoff team? 6.00.
Finally one more bit of exploratory analysis: Say we grouped players on whether they finished in the top five or not. Here's what a table of this new variable would look like when divided up by playoff appearances.
|Not Top-5 Finish||116||88|
So, it seems like playoff appearance do affect a player's MVP finish. Not exactly breaking news, but the question remains, how much does the playoff appearance affect their ultimate standing among voters? And further, how much should it?
Now, we need a model to deal with the non-continuous rank. If you remember from last week, we listed out a model to do just that. But just to remind everyone, here it is again: (Gory math alert!)
Ranki|zi = i if τi ≤ zi ≤ τi-1
zi | β ~ N(xi'β, 1)
β | φ ~ N(0, 1/φ)
φ ~ Γ(0.1, 0.1)
So, we run this model, and we get that the affect of a playoff appearance is 0.7035 to the latent value. What does that mean in terms of rank?
It means that for two exactly equivalent players, with the exception of a playoff appearance, the playoff player could get bumped up roughly two spots in the final voting. To get an idea of what we're talking about, assume that the season has finished and voting has occurred. Further, assume that a player has not made the playoffs and finished with a ranking of ___. (Pick row from the table below.)
Depending on how impressive their numbers were, if they had instead made the playoffs (assuming no other playoff statuses were affected), that same player would be expected to finish at least ___ and at best ___. (Again, see the appropriate column in the table.)
|Without Playoffs||Worst Expected W/ Playoffs||Best Expected W/ Playoffs|
So, to recap, just appearing on a playoff-bound team is worth roughly a 2-3 spot bump upward in voting for the MVP. By comparison, to have an equivalent effect on their MVP voting, a player would have to increase their bWAR by more than 3.3!
In fact, out of the chosen statistics, playoff appearances have a larger affect than WAR, home runs, RBI, batting average, and stolen bases. In other words, all the statistics. Even if you choose other statistics (ISO, OBP, wSB, UZR), playoff appearances still have the largest impact.
Now granted, when you get to the level that these MVP finalists are at, you're going to see impressive statistics from all of them. You need something to distinguish them.
But is being on a playoff team worth an increase of two spots? This probably can't be answered, as it drives at the question of " What do we mean by ‘ Most Valuable' Player?" But maybe voters should consider reigning in the weight of playoff appearances on the MVP race.
. . .
Statistics courtesy of Baseball Reference.