There appears to be a growing consensus that the Pirates' 2013 roster will feature an unusually large number of "high beta" players. "Beta" is a statistical measure of risk used by used by financial investors. High-beta stocks are high-risk stocks, meaning that they considered to highly volatile in relation to the market as a whole. A high-beta baseball player, then, is one who has a decent chance to either produce well above average, or do very little.
David Todd first introduced the term "high beta" to the Bucs Dugout community in a podcast a few months ago in reference to Francisco Liriano and his projected performance in 2013. Subsequently, Tim Williams and Charlie both posted articles in which they listed additional players who they thought fit the description (Tim's list; Charlie's list).
In light of this discussion I took great interest in the recent publication of Baseball Prospectus' 2013 PECOTA projections. One of the fascinating and unique features of the PECOTA projections system is that it calculates each player's probability of "breaking out", "improving", "collapsing", or suffering from "attrition" in the season ahead. In other words, it provides a nice measure of volatility, or "beta."
In the tables below I first provide a list of players on the Pirates roster that PECOTA sees as high-beta. In other words, these are players with significantly higher/lower than league average probabilities of breaking out, improving, etc.
Next, since Francisco Liriano was the player that sparked this analysis, I decided to compare the volatility of Pirates projected starting pitchers as group with other staffs in the National League. To accomplish this, I simply averaged the "breakout", "improve", "collapse" and "attrition" for each team's starting pitchers. I should note that I only included pitchers who are projected to make at least fifteen starts next season.
Breakout or Collapse: A look at the Pirates' 'high-beta' roster
Bucs Dugout | Feb 19