Over at the newly redesigned FiveThirtyEight, Neil Paine has written a great article, "When Spring Training Matters," considering preseason statistics for hitters. In it he weighs whether we can reasonably predict a player's regular-season performance based on his success (or failure) during February and March. Paine looks at, for example, Marlon Byrd's unexpected performance last spring, wherein he slashed .357/.393/.571 before proceeding to have his best season ever. In the end, he examines how writer Tom Tango's Marcel projections might help us root regular-season predictions in a player's spring training stats. His conclusion?
[S]pring productivity is statistically significant when predicting actual performance in the upcoming season, even after controlling for a player’s Marcel projection. However, while significant, the effect is extremely small: To raise his expected regular-season wOBA [weighted on-base average, a measure of a hitter's overall offensive value] by just a single point, a typical player would need to hit for a wOBA roughly 17 points higher than expected during the spring.
In other words, spring numbers can and should affect our predictions for a player’s regular-season production, but only slightly, and only after a particularly strong or weak performance.
Paine is at best cautiously optimistic about preseason stats, but he still lauds the showings of Detroit's Nick Castellanos and St. Louis's Kolten Wong, using Tango's model to predict a solid 2014 for each of them.
While cautious, Paine's findings should comfort Astros fans eager to see how Robbie Grossman will perform this year--not to mention a front office that's trying to extend his contract. Here are the 24-year-old's stats from last season followed by his spring numbers this year:
|Season||Plate Appearances||Batting Average||On-Base %||Slugging %||Walks||Strikeouts|
Yes, the latter is a small sample size, and, yes, Grossman will probably fail to post a .400 OBP this season. But if these numbers don't represent a "particularly strong" performance, then what does? Indeed, Grossman is affirming his ceiling as a valuable major-league starter. Given their recent talks with him, Luhnow & Co. seem to agree.*
What do you make of Grossman's excellent spring, as well as the front office's attempt to extend his contract? Let us know below.
(All stats are courtesy of baseball-reference.com.)
*On a related note, if you can find Grossman's line-drive percentage from this spring, please share it in the comment section. It'd be interesting to see how it compares with his percentage from last season (25%).