Bill Petti and I have been looking at pitches thrown at the edge of the strike zone over the last few days. Pitchers who throw a higher percentage of pitches on the edge perform better than those pitchers who throw a lower percentage. Edge% is not going to change the core traits of pitcher talent, high strike outs and low walks, but it is a nice tool to help differentiate between two similar pitchers.
Let’s examine at two pitchers, CC Sabathia and Dan Haren. My gut reaction when seeing the pair is to go with CC especially after Haren struggled through 2013. By looking at their valuations, Edge% makes the choice a little harder.
When ranking pitchers, I use a formula I created last year which only uses strikeouts and walks to get a pitcher’s valuation. The pair have almost identical projections when using CAIRO projections. Looking at their numbers it is easy to understand why.
Name: K%, BB%
Sabathia: 21.3%, 6.2%
Haren: 20.9%, 4.7%
The extra strikeouts Sabathia gets is offset by his walkss. In a draft or auction, I historically keep a few other numbers besides my Fantasy Valuation. The first extra stat is age. Try to always go with the younger pitcher. This pair are both going to be 33, so no advantage to either one. The second is K%. A pitcher is more likely to improve their walk rate than strikeout rate. Take the higher K% pitcher when given the choice. The pair is close, but Sabathia get a small edge.
Another factor is GB%. Sabathia gets a nice boost with an average GB% of ~47% over the past two seasons while Haren is closer to ~41%. The final stat I used in previous seasons was health. Both pitchers come with risks. They are both are past 30 and spent time on the DL last season which will be shown in their 2013 DL chances (2012 link). Injury concerns also exist because both pitchers saw in a drop in their velocity from the season before.
Average Fastball Velocity (mph)
Name: 2011, 2012
Sabathia: 93.8, 92.3
Haren: 90, 88.5
Looking at just the previous values, I would take Sabathia. With Edge%, I have a new value. The value correlates decently from season to season, so it is predictive. Here are the pairs values from the past 3 seasons
Name: 2012, 2011, 2010
Sabathia: 15%, 16.2%, 17.7%
Haren: 17.4%, 16.8%, 14.6%
Haren has been throwing on the edge more in recent season while Sabathia is going there less and less. Finally a mark to put up in Haren’s favor. In the end, the advantage in Haren’s Edge% is not enough to overcome Sabathia’s ground ball rate.
Edge% is another tool to help differentiate pitchers with similar rankings. With Sabathia and Haren, it was not enough advantage for Haren to push him over Sabathia, but it put the pair’s value closer together.