RBI Hitting Approach: Should it Change?

Having had a lengthy discussion with the three other coaches on our collegiate staff regarding a hitter’s approach with RISP, I thought I’d make an attempt to analyze how professional hitters might alter their approach in RBI situations. Specifically, we’re focusing on runners at 3rd or 2nd/3rd with less than 2 outs. We have eliminated all situations in which a runner resides on 1st since a coach/manager may elect to employ a strategic play (e.g. a hit & run). We have also eliminated all bunt attempts from this study. We truly want to evaluate the approach a hitter may take without external factors such as managerial strategy.

With a proven, established approach already in place in our college program, a new perspective provided the suggestion to be more aggressive and “eat the RBI early.” That is, a hitter in an RBI situation ought to look for something he can hit early in the count. This philosophy to “look for something you can hit versus drive” may allow one to avoid more strikeouts, but will it lead to success?

First, let’s establish the “standard” approach. Seems to me, the simplest situation is 0 on, 0 out. A hitter’s goal is to simply get on base. With 500,011 MLB PA’s from 2002-2012, this is clearly enough data to establish our standard. (Other situations such as 0 on, 1 out could be considered, however certain nuances of the game could affect the P/PA. For example, a 1-pitch AB by the leadoff hitter may force the second hitter of the inning to take a pitch to avoid the quick inning.) Nevertheless, we find 3.8175 P/PA with 0 on and 0 outs.  In case you’re curious, for hitters with at least 20 PA’s, I’ve plotted the leadoff hitting approach below.

ppa_0on_0out

Now we’ll compare to our RBI situations. See the table below for the base states and the corresponding P/PA for each of the population as a whole.

Outs Bases Occupied P/PA
< 2 3rd 3.8175
< 2 2nd & 3rd 3.8255

Such small differences in P/PA appear to provide no statistical difference from the P/PA in our standard situation. However, to finally answer the systemic question, we need to create a hypothesis of the overlapping data and test the statistical significance. To do so, we could do old school calculations using Student’s t-test, or we can use modern day software to simply tell us that these two distributions are actually statistically the same (that is, with 95% confidence, they are derived from identical means).  However, let’s take a look at how individual hitters (with at least 30 PA’s) alter their approach from leadoff to RBI situations.ppa_diff

The plot above shows how some individual hitters will, in fact, alter their approach in RBI situations.  Keep in mind that pitchers are taught to pitch less to contact with RISP.  That is, they will attempt to execute pitches with more selectivity.  Typically, they are taught one (or more) of three philosophies in potential RBI situations:

  1. work the “lower U” of the strike zone
  2. attempt to achieve pitch height AND width (i.e. hit the corners of the zone)
  3. go to offspeed, typically down, and especially if it’s a swing and miss pitch (resulting in more pitches out of the zone)

A quick look at PITCHf/x data tells us that a pitcher will throw strikes in the zone approximately 52% of the time to a leadoff hitter and just 45% of the time in our noted RBI situations.  Thus, a causal increase will undoubtedly occur in the hitter’s P/PA in these situations.  Next week, we’ll take a look at the RBI success rate as a function of the altered approach. Stay tuned…

 

2 thoughts on “RBI Hitting Approach: Should it Change?

  1. Quick note on the “standard” approach: did you include 1st inning leadoff batters? It’s a tiny part of the sample, but I wonder if it could give the data any bias due to actual leadoff (1st in the batting order) hitters taking more pitches per plate appearance.

    • Chris/1, great point. We contemplated this for some time and ultimately came to the conclusion to include them in the sample. Our thinking was that a leadoff hitter the first time through the lineup should have the same approach (or very similar) whether they lead off the first, second, or third innings. The point being that he’s facing a new pitcher (to see/understand his pitches for the benefit of his future PA’s as well as his teammates). Well, if we did this for the starter, we should consider doing the same for relievers. It was difficult for us to determine where to draw this line, so we decided to just include them all.