Saturday, May 31, 2014


Tim Kurkjian has an article up at ESPN that has gotten a predictable amount of promises much about the "unwritten rules" of baseball but, despite Tim's agreeable writing style, ultimately delivers very little aside from a series of "21st-century folksy" quotes.

Now what we'd really like in an article of this type is some attention to the principle of quantification. It's true that some of these so-called "unwritten rules"--the slow HR trot, pitcher retaliation for real or perceived slights of respect/etiquette, bunting in no-hit games, swinging 3-0 with a big lead--are either subject to a level of visual scrutiny not easy to capture in the data, or simply too rare to be worth counting. One suspects that most of these so-called "unwritten rules"--and there must be a bunch more than what Kurkjian decides to cover--are more related to the day-to-day necessity of simply wearing a jock strap than having much relevance to what actually happens on the field.

But there's one of Tim's five rules--yes, the one we deliberately left out of the above account (as Bugs says, "ain't I a stink-ah?")--that is actually quantifiable.

What is it? Stealing bases with a big lead. That we can count, albeit somewhat indirectly. (Forman et fils has not yet found a way to make stolen bases into something that can be traced through their "event" data--shame on you, boys!)

But not to fret, nor bitch too noted, we can get a pretty reliable count on this.

And it's kind of interesting. So far in 2014 (prior to the games of 5/31), we have a total of 957 stolen bases for the year. Of that total, 913 have been stolen with a relative score within four runs; 44 have come with the score differential at five runs or more.

That means that teams are violating the unwritten stolen base rule just under 5% of the time (4.6% to be exact).

This value is almost identical to what it was for the 2013 season (2693 SB, 136 with a 5+ run differential, 5% "unwritten rule violation").

"G#dd$%n m%th&rf^#ing Oakland A's stole
25 $#@%ing bases in 1976 with a five-run
differential! Take THAT, you %#&#ing wankers!!!"
We went back and looked at a couple of previous years, 1987 and 1976, when the SB/G ratio was at or near its highest levels since the end of the deadball era, and the numbers are largely the same. 7% of all SB attempts were violating the "rule" in '87; 4.5% were doing so in '76.

Would you be surprised to discover that the success rate of SB attempts with higher run differential are significantly better than those occurring within 4 runs? Our small sample here indicates that this is in fact the case. SB% in 5+ run differential (the "violation zone"...) is 81%, while the SB% when the score is from 0-4 runs different is just under 70%.

We're not sure if you (and the kid at left, who's more than a bit too "precocious" for his own good, if you ask us...) should get as hot and bothered as some ballplayers do when one of their opponents takes off on the basepaths when the score is lopsided, but now you at least know that your chances of being offended by an impertinent use of the stolen base is only about 1 in 20.