Wednesday, April 08, 2009

I Will Pay Attention to "The Verducci Effect" When He Uses Workload to Compare Pitchers' Workloads

How much does a contemporary baseball pitcher work? I understand the desire to express this in terms of games pitched, games relieved, games started, batters faced, and pitches thrown. I don't understand the desire to measure it in terms of outs produced.

I don't see how Verducci makes an argument about increasing workload. Perhaps his assessment is accurate, but he is essentially drawing twice from the same barrel: pitchers who record many more outs in year x will tend to record fewer outs in year x + 1 and will tend to allow more runs per out in year x + 1. In other words, Mr. Verducci is alerting us to the phenomenon known as regression.

Here is my suggestion. Mr. Verducci has been trying to isolate the effects of increasing a pitcher's workload. Perhaps he should start by measuring a pitchers' workload instead of offering a stand-alone method for cherry-picking.

This is not, it should be noted, a criticism of his results - perhaps he's right that pitchers with a sharp increase in workload are worse and/or more injured in the following season than a rigorous projection would figure. But Verducci is essentially cheating in his presentation of the argument, using outs to select pitchers instead of workloads. Do pitchers whose batters faced totals go up by more than 100 tend to break down? Isn't this the first question you would ask if you were "tracking" this?