From SABR member Aaron Gleeman at Baseball Prospectus on February 21, 2017:
“Breakout” can mean different things to different people. It can mean a prospect or untested young big leaguer establishing himself as a valuable regular. It can mean a relative unknown becoming an impact player. It can mean a well-known star making the leap to full-blown superstar, perhaps even following up a “breakout” one year with an even bigger “breakout” the next. Your own definition may vary, but in PECOTA’s case “breakout” is all about out-performing track records.
PECOTA assigns each player a “breakout rate” for the upcoming season based on their odds of beating their established level of recent performance by at least 20 percent, with historical player comps serving as an important factor. Because the entire system is based on regressed-to-the-mean, 50th percentile projections, breakout rate identifies the players most likely to leave that in the dust for their 70th, 80th, and 90th percentile upsides.
Stars like Mike Trout, Anthony Rizzo, and Francisco Lindor have relatively high breakout rates for 2017, but it’s not because PECOTA projects them to significantly improve upon their already great 2016 seasons (for Trout, that would presumably mean learning to pitch and winning the Cy Young award or something). Instead, the system pegs them as the players most capable of rising above their 50th percentile projections.
Below you’ll find 10 position players assigned a high breakout rate by PECOTA. I think it makes sense to focus on untapped upside, so I’ve removed established stars like Trout and Rizzo from the mix and also limited the pool to players projected to have at least 500 plate appearances.
Read the full article here: http://www.baseballprospectus.com/article.php?articleid=31215
Originally published: February 21, 2017. Last Updated: February 21, 2017.