We’re pleased to republish this often referenced article by Pizza Cutter that originally appeared in StatSpeak.net on November 14th 2007.

What does a year really tell you about a player? Seriously. If I gave you the seasonal stats for any player last year (or the year before), how much could you really tell me about him? If I told you he hit .300 last year, are you confident that deep down, he’s really a .300 hitter? How do you measure a year in the life?

Like a lot of things that happen out here in the Sabersphere, I take my inspiration for this (series of?) article(s?) from a conversation that went on at the Inside the Book blog. A few folks were discussing an article that I wrote here at StatSpeak on productive outs and as these things are wont to do, the conversation wandered. Inside the Book co-author MGL asked me a fair question: when I talked about productive outs, what sample size I was dealing with. Not so much how many player-years were in my data set, but for each of those player years, how many PA’s did each player have. It’s a much more important question than you might think.

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