FanGraphs introduced a new stat by MGL, the same innovator who came up with ultimate zone rating, called ultimate base runs. Essentially, the measurement is to look at just how good of a base runner said player is compared to his peers. Or if you want the full dirty details of it:
↵↵↵Runs are awarded to base runners in the same way they are rewarded to outfielders on "arm" plays. The average run value in terms of the base/out state is subtracted from the actual run value (also in terms of the resultant base/out state) on a particular play where a base runner is involved. The result of the subtraction is the run value awarded to the base runner on that play.
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It might not surprise you to note that Michael Bourn has added 11.7 runs to the table over his Astros career with his baserunning. It also may not surprise you to learn that Carlos Lee has subtracted 19.4 runs from the Houston tally by being as slow as Friday afternoon. One surprising result? Brett Wallace has already lost the Astros four runs on the bases this year alone. I knew he wasn't a sprinter, but I didn't think he was as slow as Lee.
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