A little over a year ago I published the results of a study that examined which metrics were most consistent on a year-to-year basis for starting pitchers. My colleague, Matt Klaassen, followed up and expanded on that study recently here at FanGraphs. Matt’s study also focused on starting pitchers–those with a minimum of 140 innings pitched in consecutive years.
Recently I was asked the following on Twitter:
@billpetti have you ever done research on reliever year-to-year performance variability? I’d like to see the common wisdom tested
— Justin Overfelt (@j_felt08) May 21, 2013
I can’t speak specifically to what the common wisdom is Justin is referring to, but I can certainly run the correlations for relief pitchers and compare them to what I found for starters.