Twins 8, Brewers 6 and Stealing Bases
by, 05-31-2013 at 12:26 AM (746 Views)
The Minnesota Twins won last night, swiping (and sweeping) the season series from the Milwaukee Brewers. The victory raised their record to 23-28 which translates to a 73 win pace over the course of a 162-game season.
But I want to talk about some different swiping that happened, or more accurately, did not happen. In the bottom of the sixth inning, Aaron Hicks was caught trying to steal second base. What struck me as strange at the time was that there were runners on the corners and one out. It seemed like a stupid decision to attempt that at the time, as it can short-circuit a good scoring opportunity. However, one always looks stupid when one is caught. So I wondered, was it as risky as it seemed?
It turns out – I studied this exact situation last year on 5/11, only it was Denard Span that was thrown out. Here’s how that went:
Tonight, though, I want to take it a step further. How does it compare to other situations in which one might try to steal a base?Generally, one studies something like this using Palmer & Thorn's Run Expectancy Matrix. It's a neat grid that shows, given a certain number of outs and people on base, the average number of runs that should score that inning, based on 75 years of major league games. It was published in The Hidden Game of Baseball by Pete Palmer and John Thorn. You can find it here.
Here's the numbers we care about:
1. 1.088 - That's how many runs a team on average would score with runners on 1st and 3rd and one out.
2. 1.371 - If Span would've stolen the base, that's how many runs the average team would've scored.
3. 0.382 - If he was caught, that's how many runs the average team would score.
So Span risked a gain of .283 runs if he stole that base, but a loss of .706 if he was caught. Converting those to percentages, if he steals that base 71% of the time, the team breaks even. That's not especially different than the 2/3 view that is the case for most base stealers. This wasn't especially risky.
There are 12 situations where a runner might try to steal a base without coordination with the other runner. Here they are:
Runner on 1st, 0 outs
Runner on 1st, one out
Runner on 1st, 2 outs
Runner on 2nd, 0 outs
Runner on 2nd, 1 out
Runner on 2nd, 2 outs
Runners on corners, 0 out
Runners on the corners, 1 out
Runners on corners, 2 outs
Runners on 1st and 2nd, trying to steal 3rd, 0 outs
Runners on 1st and 2nd, trying to steal 3rd, 1 out
Runners on 1st and 2nd, trying to steal 3rd, 2 outs
And here they are again, ranked by just how risky they are. The percentage indicates how often one needs to succeed for it to be a good decision.
92.51% - Runners on 1st and 2nd, trying to steal 3rd, 2 outs
91.10% - Runner on 2nd, 2 outs
79.67% - Runner on 2nd, 0 outs
77.69% - Runners on 1st and 2nd, trying to steal 3rd, 0 outs
77.25% - Runners on 1st and 2nd, trying to steal 3rd, 1 out
75.31% - Runner on 2nd, 1 out
74.74% - Runners on corners, 2 outs
71.39% - Runners on the corners, 1 out
70.73% - Runners on corners, 0 out
65.20% - Runner on 1st, 0 outs
63.41% - Runner on 1st, one out
60.06% - Runner on 1st, 2 outs
So it wasn’t patently stupid, like trying to steal 3rd when you’re already in scoring position. But it was the 2nd riskiest situation in which to try and steal 2nd base. The only thing that would have been worse was if it could have ended the inning.