As we discussed Jeff Francoeur last week, the comments section spent a fair amount of time on Fangraph’s baserunning metric. You can count me as among the many who have just enough knowledge on the subject to be dangerous. The first thing that all or most of us, anyway, think of when you hear ‘baserunning’ is something that measures speed, steals, ability to advance on the bases and on and on.
In truth, steals and caught stealing were already factored into a player’s WAR before the baserunning (BSR or UBR – they are the same) metric came along. In addition, some of the other things that would logically be associated with the TERM baserunning have nothing to do with the METRIC Bsr. That said, here is a link to a far better explanation of Fangraph’s Bsr metric and I hope everyone with a question about it will click here.
A quick and dirty explanation contained in the Mitchel Lichtman article linked above:
Let’s say that there is a runner on second and one out. A ground ball is hit to the SS. Let’s say that on the average, in that same situation, the runner advances safely to third and the batter is thrown out 20% of the time, he stays put 70% of the time, he gets thrown out at 3rd 5% and beats a throw to third 5% of the time (batter safe on a FC). And let’s say that average base/out run expectancy (RE) of all those results, weighted by their frequency of occurrence, is .25 runs (all the numbers are made up). If the runner advances and the batter is thrown out, and the resultant RE is .5 runs, then the runner gets credit for .25 runs (.5 minus .25). If he stays put, and the average RE of a runner on second and 2 outs is .23 runs, then gets “credit” (he gets docked) for -.02 runs (.23 minus .25). So basically a runner gets credit for the resultant run value of what he does minus the average weighted resultant run value of all base runners in that situation.
I guess, more than anything else, reading the paragraph above and the entire article linked to just before will hopefully give all a clearer understanding of what ‘Bsr’ measures and what it does not. Knowing that steals, caught stealings, grounding into double plays, stretching singles into doubles or lumbering a sure double into a single are not included – basically because they are already accounted for in other metrics. It is more a measure of efficiency on the bases than speed or even hustle. It is what it is and attempts to quantify a portion of the game that previously had not been measured and not to define what would logically be inferred under the heading of ‘Baserunning’.
Of course, the primary criticism lately around here has been that Jeff Francoeur’s Bsr is lower than even that of Billy Butler. Now, we know that Billy Butler is not good at baserunning in the broad sense of the word. He is the classic ‘time him with a sundial’ runner and, while there is not a whole lot Butler can do to change that in any appreciable manner, Billy gets his deserved share of criticism. The very nature of Butler’s cement feet, however, cause him to not consider trying to score from first on a double or things of that nature and hence he avoids piling up a lot of the ultimate negatives of baserunning: outs.
That Billy Butler is rated higher in ‘Bsr’ than Francoeur is not Fangraphs’ saying that Billy Butler is a better overall baserunner than Francoeur, it is simply a measurement of a certain part of what we consider baserunning and one in which Frenchy gets his a lot of negatives (8 outs on the bases not counting caught stealings). The positives that, at least to some extent, would outweigh those negatives (the hustle double) are measured in a different metric and hence Jeff’s numbers in Bsr take a greater than expected hit.
Again, it is what it is, but maybe this gives us just a touch more understanding of the metric.