The Roto Grotto: catching up with pitcher stats

So far, I’ve used hitter statistics for all of my examples. Really, hitter stats can demonstrate every concept that applies to either hitter or pitcher fantasy stats, but I spent this week catching my pitcher stats up to my hitter stats. Now, I can show comprehensive 2012 results.

First, here is the top-25 total Z-scores of pitchers based on the league mean and standard deviations of each roto stat from 2012:

There are several similarities between pitchers and hitters. Saves are a stat that applies only to certain types of pitchers. In that way, they are similar to stolen bases. Each starter has the same small negative Z-score for Saves of -0.32.

ERA and WHIP are the pitcher rate stats, which are analogous to batting average for hitters. Rather than scale to at bats, I scaled ERA and WHIP to innings pitched. The main difference is that both ERA and WHIP scale from high to low rather than low to high, and so I multiplied the Z-scores for those categories by negative one.

Remember that all Z-scores are based on per game numbers with a fairly small minimum innings qualification. Most names are the ones you would expect, but that is why pitchers like Chris Tillman and Brett Anderson made or nearly made the list.

Finally, hitter and pitcher totals can be combined to produce apples-to-apples comparisons based on total Z-scores:

Even though starting pitchers by their nature contribute in only four categories, David Price and Justin Verlander still made the top-10 overall by total Z-score last season. Of course, total performance is not the only justification for drafting a player. Pitcher and hitters have different chances of injury, declining performance, and replacement levels.