Isolating the Hit Tool

A couple of months ago, I submitted to these pages a piece in which I attempted to identify five-tool players by the nerdiest possible numbers. For each of the tools — hitting for average, hitting for power, etc. — I used an advanced metric that would serve as a sort of proxy for that tool. For average, it was contact percentage; for power, it was home runs per batted ball; for speed, it was Speed Score; for fielding, it was a combination of UZR and the WAR positional adjustment. The methodology, if imperfect, at least had the effect of framing the conversation.

There was some question at the time regarding what exactly is meant by the “hit” tool — and how we define it is likely to have an effect on the how we measure it.

Fortunately for all of America, J.D. Sussman of Beyond the Box Score actually wrote a meditation on the hit tool back in March — a piece for which he was able to elicit the following definitions of the hit tool from people who know a thing ot two about a thing or two.

Here’s how Sussman’s correspondents replied:

Rene Saggiadi (European Talent Evaluator): It’s simply the ability to square balls up.

Jason Parks (Baseball Prospectus, out of context quote): a “smooth swing and excellent barrel awareness that should allow [one] to hit over .300.”

Jim Callis (Baseball America, Interview): Someone’s pure hitting ability.

Jeff Reese (Bullpen Banter): The hit tool is evaluating the aspects that are conducive to high batting averages.

Additionally, Kevin Goldstein, Ben Badler, and Jim Callis noted that MLB regulars with 80 hit tools included Albert Pujols, Ichiro Suzuki, and Joe Mauer.

While attempting to reconcile these definitions with which advanced metric might be most representative of them, something revealed itself that should have been obvious — namely, that many of the players who have posted the highest batting averages over the last decade or so are also among that period’s best home-run hitters. That is, of course, because home runs are hits, too, and count towards batting average just the same.

Among the 552 batters who accrued more than 1000 plate appearances between 2002 and ’11, here are the top 10 per batting average:

To get a sense of the impact of home runs on batting average, consider the following list. It’s the top-10 list for batters per “non-home run batting average” (or, NHRAvg). To calculate NHRAvg, I divided (hits – home runs) by (at bats – home runs). Essentially, we’re looking at all the at bats that didn’t end in a home run.

In fact, only three players from the first list appear on the second one: Ichiro Suzuki, Joe Mauer, and Todd Helton.

It’s not at all my intention to argue that the players on the second list have a superior “hit tool” to the ones on the first list. Rather, what I mean to say is that the integrity of the five tools is most well preserved if we minimize — and, hopefully, eliminate — those areas where they might overlap. If one tool correlates very highly with another, then the importance of said tool is diminished. If a player’s power is helping to sustain a high batting average, too, isn’t he receving double credit for having excellent power? And how do we rate the hit tools of players like Starlin Castro, Derek Jeter, and Michael Young — that is, players with high non-home run batting averages, but who lack homers?

It was this thought, for example, that led me to use home runs per batted ball as the proxy for the power tool — because using ISO, for example, would credit those players who are adept at turning singles into doubles and doubles into triples. That’s a different thing than power-on-contact — and anyway, doubles and triples are part of Speed Score.

In any case, it’s not my intention to solve the problem here. Rather, I’ve only intended to highlight this one point — that there’s inevitably some interaction between the “hit” tool and “power” tool if we define the former in terms of sustaining a certain batting average. Conversely, there are players who might fulfill other definitions — like Parks’ and Saggiadi’s above — while posting slightly lower batting averages, owing to a lack of home-run power.