This morning, Bill Petti posted an article on hitter volatility. With this research he wanted to show if players are consistent throughout the season, or if they are someone who has a big game followed by a handful of poor games.
Essentially, the idea is to understand whether there are appreciable differences in how players distribute their daily performances over the course of a season. For example, if you have two hitters that are roughly equal in terms of overall skill (i.e. both are 25% better offensively than the league average) is there a difference in terms of how much each is likely to vary from their overall performance on a game to game basis? Is one hitter more consistent day in and day out, while the other mixes in phenomenal performances with countless 0-4 days
He came up with a metric called VOL, and the lower the VOL the more consistent the player is. For example, in 2012 Elvis Andrus was the second least volatile player during the season. His VOL score was .384, which comes out to a 77 VOL-. 100 is considered league average, and anything below that is considered above average, and anything above that is considered above average.
Bill also found relationships between year 1 VOL and year 2 VOL, but you will have to read the article to see those results. As he noted he still has a lot of work to be done, but going forward this could be something that helps out a lot when we want to see who the most consistent players in the game are.
Questions for conversation:
1. Anyone at the top of the list surprise you?
2. Anything Bill should re-consider?