Starting Pitcher DL Projections (Part 2 of 2)

Yesterday, I went through the formula used for predicting which starting pitchers have the greatest chances of going on the DL in a given year. Now here are the projections for 2011. Besides revealing the list, a few other points and possible improvements to the process will be discussed.

First, here are the five most and least likely starting pitchers (>20 GS and >120 innings in 2010) to go onto the DL in 2011 (creating these projections is still a work in progress, so no one should take too much stock in them right now):

There are no real surprises on the list, with young experience pitchers ~25% less likely to go on the DL than older injured pitchers. A complete list of players can be found here in this Google Doc.

The projections estimate that 45 of the pitchers will go on the DL sometime during the season, which is 39% of the pitchers being examined. Looking at 2010, the projections would have predicted 43 players going on the DL and 37 actually did or 34% of the total pitchers.

Knowing just the chances for going on the DL is not the entire picture. The number of days lost also needs to be known, but I have not figured out a good way to get the days lost yet. Instead, here is a chart to use with the number of days lost for each trip to the DL for this group of starting pitchers:

One encouraging sign from the proceeding graph is that, once on the DL, the pitcher has less than a 20% chance of missing more than 90 day in the season.

Besides figuring out the possible days lost, I may look into a couple other improvements in the future, as follow.

1. Use Tom Tango’s fan playing-time projections. Instead of looking at what a pitcher did the year before, it would look at how much fans think the pitcher will pitch in the coming year. He has only generated them for the past two years, so the data set used to create the projection would be limited.

2. Look at the pitcher’s fastball velocity. It seems that pitchers who throw harder are more likely to end up injured than pitchers that are soft tossers. I may add these pitch speeds in when I get around using Tom’s playing-time projections.

With the starting pitchers done for now, I will be moving on to relief pitchers next. Hopefully, I will have some data in the next couple of weeks.