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There has been an ongoing discussion at Baseball Think Factory about Keith Foulke’s usage last year. Foulke did have a strange record, in that many of his appearances were in low-intensity situations. This is unusual for a closer.
Two of the issues raised were whether Foulke’s low-intensity appearances occurred primarily in the beginning of the season, and do high-intensity appearances tend to be “clumped” together.
The best way I know to show that is with a graph. So here ‘tis:
The lines/bars represent each of Foulke’s individual appearances, and the superimposed line is a ten-game rolling average. P is a measure of the importance of a reliever’s appearance.
As you can see, there is some natural clumping of high-intensity situations, and he was used a lot in low-intensity situations from mid-April toward the end of May.
For reference, the top closers averaged around 0.09 in average P Value over the full season, and Foulke came in at 0.067.
You can find a full definition of the “P Value” in my Hardball Times article. More bullpen information like this is available in The Hardball Times Bullpen Book.