THE BOOK--Playing The Percentages In Baseball

I messed up the order.  The ones I termed “strategic” are more like “quasi-intentional”, and those were the run value of the walk is super high would be very strategic, since you’d really have to go out of your way to try to walk someone here.

A couple years ago there was an article in the New York Times about “strategic walks”.  (As I recall, the point was to show that pitchers like Maddux or Glavine employed this strategy.) One of the points made was that, in measuring the value of a walk drawn by a batter, you should subtract the batter’s slugging average—apparently the theory was that by walking, the batter is “losing his chance” to hit a single, double, etc.

This seemed somewhat odd to me, as it assumed that a plate appearance could be bifurcated into a two step process—first, walk or no walk; second (if no walk), hit or out.  But maybe it is true to some extent if pitchers do in face employ “strategic walks”. 

So (ignoring the impact of stolen bases), is a walk drawn by Lance Berkman worth less than a walk drawn by Willy Taveras?

Found the article:

http://www.nytimes.com/2006/04/30/sports/baseball/30score.html?scp=10&sq=Alan%20Schwarz%20and%20Greg%20Maddux&st=cse

I remember that article.  I commented on it too, I’m sure.

Basically, if Manny Ramirez is +.10 runs per non-BB PA, then walking him (+.33 runs) will add +.23 runs to our initial expectation.  If Juan Pierre is -.05 runs per non-BB PA, then walking him will add +.38 runs to our initial expectation.

So, it is much crazier to walk Pierre (or the pitcher) than to try to let him hit.

Indeed, the time that the IBB becomes a necessity is when the win value of the IBB adds less than the win value of the non-BB PA.  If for example, Manny in some leveraged situation would add +.05 wins in a non-BB PA, and if you walk him he would add +.04 wins, then you MUST walk him, because you are really removing .01 wins than expected.

Interesting.  I have always suspected that the run value of walks for slugging players was less than that of non-slugging players, simply because the former tend to be draw walks in situations where the BB is not worth the usual (average) .31 (or so) runs (such as with bases open - the unintentional intentional walk).

That is certainly easily testable.  We can look at the PBP data and figure out the value of the average non-intentional walk for sluggers and non-sluggers, dividing them anyway we want.  My guess is that for non-sluggers it is going to be worth around .33 runs and for sluggers, .30 runs or something like that. Obviously it is not going to be binary like that - it is a sliding scale.

If my theory is true, then we are slightly overvaluing sluggers with high walk totals like Dunn, Bonds, and undervaluing light hitters with good eyes and high walk totals, like Kendall, etc.