I mentioned in a previous column that the 2008 Bill James Handbook is now available and so I thought it would be interesting to take a look at how the Baseball Info Solutions (BIS) baserunning numbers compare to our five metrics.
Although what BIS includes is a subset of the five metrics (they don’t include advancing on fly balls other than sacrifice flies nor advancing on ground outs) and includes an indirect and context dependant metric (percentage of times the runner scored when on base), they do now include a category called Stolen Base Gain (SBG) defined as simply stolen bases times two minus caught stealing that allows to make some fairly direct comparisons. In that vein, below I’ve listed the players in The Handbook (I apologize in advance for any errors in transcription since this was done by hand scanning all 400 listings) who in total gained 35 or more bases or lost 20 or more in the BIS system. To the right you’ll see the roughly equivalent number of EqRuns minus EqSBR, EqSBR, and the total number of runs (EqRuns) followed by the player’s ranking.
Obviously there is a strong correlation here as only Dave Roberts, who ranked third in our system at +8.4, was left out of the BIS leaders (he did gain 31 bases which would have put him in the next five). In addition, both Orlando Cabrera and Willy Taveras come out looking better in the BIS system than in ours although both have been consistently among the league leaders with Cabrera taking third in 2006 at +8.6 and Taveras seventh at +6.5. The differences in cases like these are typically due to the added context our measures take into consideration (and sometimes the fact that we include pick offs), for example causing a runner to get less credit for advancing from first to third if the ball is hit to the right fielder with two outs than to the left fielder with nobody out. Careful readers will note that our numbers listed here have changed slightly from the previously published version since a few small wrinkles were squeezed out of the system.
Also new this year in The Handbook is a table of team results and so below we can compare the BIS team results with ours.
The overall correlation here is pretty strong at r=0.75 with the largest difference being the Dodgers, who ranked 22nd in the BIS system but third in ours. While BIS shows them at -40 bases gained our system has them at +9.0 in EqHAR (advancing on hits) accounting for almost all of their total of +9.6. After drilling down into this metric it’s not obvious why the difference is so large. The Dodgers did well in advancing from first on a double (+5.3 in 62 opportunities and never being thrown out) and advancing from second on singles (+3.9 in 176 opportunities and thrown out three times) while losing a little on advancing from first on a single (-0.3 in 269 opportunities and thrown out twice). This may be a case where the Dodgers had an unusually large number of opportunities that were high risk and high reward that paid off for them.
In any case, overall it’s nice to see that these two systems do substantially agree.
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