AWHIP

Introducing AWHIP

by Drew Duffy 4/17/23

I have begun an early stage creation of a new way to interpret WHIP. While WHIP is an imperfect stat (just like all other ones), I think that there is an ability to enhance the metric to be more indicative of overall performance. Some shy away from WHIP, including Tim Dierkes of MLBTradeRumors. He makes the case that WHIP is almost too simplified, which creates a skewed view of overall evaluation. His argument is that the two factors that come into the equation, Walks and Hits, are better off being treated separately, since they are indicative of vastly different skills. As he notes in his article, Dierkes states how simple the calculation of the stat is. To calculate WHIP, all you have to do is sum the walks and hits that a pitcher gives up and then divide them by the total innings pitched. 

This is the equation for WHIP:

WHIP = (Walks + Hits) / Innings Pitched

Now, I have seen other people note the oversimplification of the statistic, but the alternative methods are not great in my eyes. I have seen some people completely get rid of WHIP as a useful statistic, which has some merit though the premise of the idea is a good one. I have seen an alternate method that treats each batted ball outcome similarly to the way that Slugging Percentage is calculated for hitters. This means that singles are the baseline, doubles are worth 2x, triples 3x, and home runs 4x. This is closer to where I see value in adjusting WHIP. 

In one of my past projects, I used weighted values based on each outcome of the at bat to show Aaron Judge’s “Offensive Bases Affected”, as I called it. I believe this gives a more appropriate value to each outcome, which can be used here in my AWHIP calculation. FanGraphs publishes the wValue for all different outcomes of an at-bat, which serve as the coefficients in my new model. I also added in HBP as part of my calculations, one thing that WHIP does not currently include. This model gives a more encompassing look at a pitcher’s 

This is my equation for AWHIP:

AWHIP = (SUM of (# of occurrences X wVal of event)) / Innings Pitched

For the 2022 Season, here are the FanGraphs wValues:

wBB wHBP w1B w2B w3B wHR

0.689       0.72     0.884     1.261       1.601       2.072

For each event, there is a number of times that a pitcher surrenders that result. I summate all of the occurrences then divide them by the total innings that a pitcher pitched. This gives me a number that is an adjusted WHIP, or AWHIP. 

First, I looked at two pitchers who had identical WHIP from last season. Corey Kluber and Jose Quintana both pitched to a 1.213 WHIP in 2022. Here are their numbers: