Hosmer's Dash and Decision Making
Monday, November 2, 2015 at 12:41PM
Joe Peta


Decision Making and Hosmer’s Dash

One of the things that professional blackjack players, stock traders (especially those who specialize in options) sports bettors and poker players understand is that making a decision with negative expected outcome is often the correct decision.  In fact, one of the reasons it’s very hard to rise to the top of the profession in any of those endeavors is that proactively making a decision with a negative expected outcome goes against the wiring of the human mind.  A wealth of behavioral finance textbooks will tell you that defending an action that is most likely to fail is an uncomfortable state of mind.  Baseball bettors have to do this all the time when deciding whether to back an underdog on the money line.  Almost always, one expects to lose when betting on an underdog – the question is can a decision with an expected negative outcome actually have a positive expected value.

In the wake of Eric Hosmer’s decision to make a dash for home plate in the top of the 9th inning, all you have to do is go through the Twitter feeds of baseball fans and analysts or listen and read the wealth of commentary both spoken and written about the play.  There is a huge, quite vocal faction of analysts who believe that Hosmer may have scored on the play but it was a foolish decision.  Bad process + good result = dumb luck is essentially what they are saying*.

*(Or as the most adamant -- and clever -- tweet directed at me stated, “//Hosmer drives off cliff.//Car lands on ship covered in pillows and millions of cash//Joe Buck: “Unbelievable driving!”)

I say, hogwash.  It wasn’t bad process.

First of all, let’s stipulate some points of agreement.  It’s not as simple as pointing to screen grabs that show Hosmer out of the picture when Lucas Duda’s throw got to Travis d’Arnaud’s glove, but without a doubt a better throw nails Hosmer at the plate.  There was a substantial window to the left of d’Arnaud for Duda to throw the ball through, and if he does it’s not a particularly close play at the plate.  Further, for a professional first baseman, even one that is a substantially below-average fielder as Duda is, it’s a throw from 90 feet away that is successfully made more than 50% of the time.  So stipulated.

Therefore, the chorus of Hosmer’s critics contend, it was a bad decision because it’s a decision that most likely results in a game-ending loss.  I also concur.  However, if Hosmer decides not to break for the plate, there is also a probability way in excess of 50% that the game ends in a loss.  So is that the wrong decision too?

Options traders constantly buy and sell options that have little chance of being profitable.  Professional blackjack players hit on 16 all the time – even though the decision instantly ends in ruin more than 60% of the time.  The same critical reasoning that make those decisions proper apply to Hosmer’s choice as well.  The only relevant factor in evaluating Hosmer’s decision is this:  Are the odds of failure, which dominate both choices, smaller by running than by staying at third base?

During the 2015 season, there was a runner on third base with two outs 2,865 times (all data per baseball-reference.com.)  On 680 of those instances, the runner on third scored.   That’s a success rate of 23.7 percent, or, of course, a failure rate of 76.3 percent.  In 2014 there were 2,875 instances with a success rate of 22.5 percent.  So staying on third has a failure rate in excess of 75 percent, of that we can be sure.  However, with that many observations, nearly 6,000, we’re getting a baseline probability that reflects the average across all of major league baseball. 

But Jeurys Familia was on the mound for the Mets and with a lifetime ERA of 2.42 and supporting peripheral skills he is absolutely, without question, a well-above-average pitcher.   We’re starting to get into small sample sizes here, but just for fun let’s look at Familia’s success rate in that situation.  Ten different times Familia has faced a batter with a runner on third and two outs and the runner has never scored.  Now, Alex Gordon, the batter-in-waiting when Hosmer broke for home, is not an average hitter either (even though Ned Yost hits him 8th in the lineup – but that’s a different topic worthy of 2,000 words) but he’s not as close to as much above-average as Familia is.  Over his career Gordon has succeed in driving home the runner from third with two outs just 17.9 percent of the time.  Make any adjustment you want to factor in what you think Gordon’s batting average will be against Familia in that situation, but I think you have a hard time getting that figure in excess of 22 percent.  (Speaking of small sample sizes, please don’t let Gordon’s home run in Game 1 cloud that calculation. Also I am ignoring two other points that do little to change the decision, if Gordon walks run-expectancy increases but we have to start debating the skills of the next hitter, most likely pinch-hitter Kendrys Morales batting left and the chance that a hit that successfully brings Hosmer home would have also eventually plated Gordon, which includes a Gordon home run.)

In any event, I’m willing to concede that if Hosmer stays at third base he would have scored about 22 percent of the time.  We’ve agreed that Hosmer was “lucky” in the sense that he was unlikely to score by making his break for the plate, but the fact that he was more than likely to be out at the plate is really irrelevant.  The relevant question to ask yourself is, “Was there a greater than 78% chance he was going to be out at the plate?”  Or stated another way, “Do you really think Lucas Duda successfully completes that play 80% of the time?”

I think the answer is “no” but even if you think the answer is “yes” the decision is so close that there is no way you can label Hosmer’s Dash as bad baserunning.  As any really experienced poker player will tell you, aggressive poker equals winning poker and the same principle applies here.


Mop Up Duty:

Joe Peta is the author of Trading Bases, A Story About Wall Street, Gambling, and Baseball*  (*) Not necessarily in that order, a Dutton Books/Penguin (U.S.A.) publication currently available wherever books are sold.  Here are three on-line booksellers you can currently choose from:




He is also the author of Trading Bases, the Newsletter, a companion piece to the book.  If you have been forwarded this issue and would like to be placed on the mailing list, please send an e-mail to tradingbases@gmail.com

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