This is a look at baserunning runs, excluding stolen base attempts. Here’s the basic method:
- For all plays, we consider the lead runner only.
- We figure out the average change in run expectancy for the lead runner for each non-discretionary running event – typically a ball in play (either a hit, error or out). Those plays are grouped by:
- The number of outs in the inning.
- The type of event – single, double, etc. (A fielder’s choice is considered an ordinary out.)
- For batting outs, whether the ball was hit in the air or on the ground.
- The position of the player who fields the ball.
- Then we figure the change in run expectancy for the lead runner on each individual baserunning play. For a non-discretionary event, we subtract the average value of that running play. For a discretionary running play, such as a wild pitch or passed ball, we do not – a runner is not penalized for the decision not to run.
That gives us our baserunning runs. Your leaders (and trailers) for 2009:
Your typical caveats apply – don’t read too much into a one year sample. Remember that players at the extremes during any sample tend to regress to the mean as the sample increases, etc.
The full list is available here.