Regression and Recovery Candidates for 2013

A few weeks ago here at Beyond the Box Score, I released three predictive models for batted ball data in a Fanpost-- Introducing pLD, pFB, pGB: Accurately Predicting Batted-Ball Info. The formulas in that data-set showed impressive accuracy; however, I would like to apply and test its validity on the 2013 season. So I have taken all qualified hitters in 2012 and created a table with their projected slash line of LD/FB/GB.

Note: the article includes the methodology on deriving the models and will help your understanding of the results we will find today. Also in the piece, the models used are included.

RESULTS

Here is the table with the 2012 raw data and the predicted totals for 2013. The wDIFF's are essentially 2 year weighted differential totals. So it is the differential between the 2013 projected batted-ball number and the player's two year average in that batted-ball category. Also, please note that the 0's are essentially NULL because they were rookies in the 2012 season:

Now that we have these visuals we can identify the players who are candidates for recovery or regression in 2013. Keep in mind that the predictive models are independent of each other. As a result, don't expect a guy like Stubbs to improve in every category but instead see some recovery in one area and perhaps regression and/or stabilization in the other. In other words, the totals have an indirect variation with one and other. In the future, these models will be compounded to create a pBABIP metric, in which the BIP% is a weight along with a regressed BA for each batted ball type. For now each metric is a separate entity with no statistical relation to the next.

With that being said, in the pLD category, we expect to see some serious regression for Alex Rios, Michael Young, and Alex Gordon. Expect to see a large drop off for Prince Fielder, who enjoyed a line-drive fiesta last year with the Tigers hitting 128 after never enjoying a season with more than 93. Coincidentally, Fielder had a 14 point uptick in his batting average despite his OBP inching down a little while his SLG declined nearly 40 points. I am sure Torii Hunter wishes to see the same phenomenon occur in Comerica to himself when he joins the Tigers opening day lineup in 2013 . However, his LD rate is project to stabilize with an uptick in the amount of FB's. Sorry Yankees fans, Derek Jeter is projected to have a steep regression to his LD total in 2013. Interesting recovery candidates include: Mark Trumbo, Drew Stubbs (playing time assumed), Cameron Maybin, Kevin Youkilis, and Mark Teixeira.

In the pFB category look out for a FB drop off from Jimmy Rollins, Edwin Encarnacion, Ian Kinsler, Aramis Ramirez, Aaron Hill and J.J Hardy. In other words, we can assume for some power drop off in these players. Meanwhile, recovery is projected for Carlos Gonzalez, Yunel Escobar, Cameron Maybin, Kevin Youkilis, and Jamey Carrol. A regression in FB could mean less power for some break-out power players but also a return to form for certain players who can expect their batting average to improve. For Carlos Gonzalez he has seen his fly ball total decrease from 167 to 117 in the last two years. With pFB projecting roughly 140 FB for Cargo in 2013 expect his power to return to his career norms, especially because a good portion of those extra FB's may come from within Coors.

Now time for pGB. Those who we should expect a notable regression in their GB totals in 2013 include: Derek Jeter, Ichiro Suziki, Martin Prado, and Elvis Andrus. For improvements Josh Hamilton, Danny Espinosa, and B.J Upton seem set to see an increase in their GB rates. For Dan Uggla, expect a large increase. Uggla experienced a futile campaign in 2012 arguably his worst season to date. His pGB indicates that we should see Uggla's ground-ball output to be around 160. If anyone has seen Uggla hit, he mashes ground-balls but is prone to hitting in-field flys (16.9% in 2012). Uggla is a strange case as he had a career high in LD% but saw a career worst batting average. Given that LD is the most probable batted ball type to land for a hit, we should have seen a recovery last season instead of that atrocious .220 batting average. Given this information and his positive pGB and pLD predictions, I think its safe to say we will see some kind of recovery from Uggla, but the days of him hitting in the .260~.280 are over.

Overall, I like the chances of seeing B.J Upton and Danny Espinosa improve their batting averages in 2013. Another player that I like for 2013 is Ian Kinsler. After hitting a career high 213 GB's in 2012 following a career average of around 147 GB per season, I find it interesting to see his FB rate is projected to decrease. If in fact Kinsler's FB rate drops, expect to see an uptick in his ability to hit line-drives and ground-balls, assuming his BIP and BABIP remains constant. Meanwhile, Cameron Maybin is a strong recovery candidate for 2013. If his average hovers around .270 and .280 look for Maybin to be one of the most valuable center fielders in the game given his exceptional fielding for his position. Lastly, look for Mark Teixeira and Kevin Youkilis as veteran players prime to bounce back slightly.

After the 2013 season I will take the raw 2013 batted-ball data for all qualified players in this case study and analyze the precent error. For now, all we can do is sit and watch through another glorious season of our national pastime.

You can contact Max Weinstein on twitter @MaxWeinstein21

All statistics courtesy of Fangraphs