A hit is simply this: a ball put into play that slips through the defensive positioning and ability of the fielders. Are either of these factors within the control of the hitter? No, not really. The difference between a double to the gap or a caught liner is simply “was the shift on?” A hit up the middle versus a double play can be a question of whether or not the shortstop was holding the runner at second on. The difference between a liner down the line and a caught ball is whether or not Ryan Howard was playing 1B or DH in an interleague game.

Clearly the hitter controls or exercises some control over the direction of the ball and the strength of contact by “timing” and “squaring” the pitcher’s offering, but once the ball is in play, whether or not that balls is a “hit” is almost entirely depending on the positioning and ability of the defense. The glaring exception to this rule, of course, is the home run. That is a “hit” truly and 100% earned, although fielders can even steal those sometimes.

In short, hits are not something a player particularly controls. There is a lot of luck involved and over long enough sample sizes, luck tends to average out. It is not shocking, therefore, that over 162 games against 20 or so teams, a player’s collective “balls in play” (BIP, non-HR balls put into play) which are converted into hits tend to fluctuate between a normative band of numbers (usually between .290 and .310, though a player’s BABIP varies based on his speed, types of contact (each of GB, FB, LD are differently correlated with BABIP), and strength of contact). Last season, the lowest BABIP a team had was .285 (the Reds) and the highest a collective team had was .326 (the Angels). Only four teams did not have a collective BABIP between .288 and .312 last season. The MLB average BABIP last season was .302.

Thus, knowing that BABIPs tend to normalize and that hits are mostly defendant on BIP averages, it is not so difficult to conclude that hits are a poor measure of a hitter’s ability — if for no other reason than a hit is more in the fielder’s control than that of the hitter.

Is batting average also a poor metric by which to measure a player and team’s ability to score runs? I will pretend that you answer my rhetorical question by stating “of course it isn’t, that’s why we have RBIs” because 1) runners being on is situational and independent of a hitter’s ability, 2) the normalizing effects of BIP do not cease effect in high leverage (clutch) situations, and 3) clutchiness really does not exist (read the link for more info on why).

To answer my question, I posed another question: how does one score runs? Scoring runs is accomplished by a two-step process: putting runners on and moving them over. Putting a runner on base is measured by On Base Percentage (OBP), which accounts for both hits and walks. Hits are largely a function of luck, while walking is more of a skill (a player’s ability to read the strike zone and determine a pitch’s trajectory is not dependant on outside factors other than an umpire’s [in]ability to call balls and strikes). Moving the runner over is measured by the hitter’s power, or ISO (Slugging Percentage (SLG) minus Batting Average (BA)). A double will move a player over more bases than a single and a triple more than a double, while a home run will clear the bases and score the batter. The higher a player’s power, the higher his SLG. Because SLG is measured as ((1B)+(2*2B)+(3*3B)+(4*HR))/(AB), a player with absolutely no power (hits only singles) would have a SLG of 1B/AB, where H (hits) would be equal to 1B. Thus, a player with no power’s SLG would be equal to his BA (BA=H/AB). As a player has more power, his SLG becomes larger than his BA. This is why a player’s power is measured by ISO.

Where, I dare ask you, is “hits” a component of this runs-scoring model? It exists, hidden away in getting on base and to some extent moving the runner over, but the “ability to get more hits than the average guy” component of the game that most people attend to when they say “he’s a good hitter” is better encapsulated in a hitter’s strikeout rates. A player who puts more balls in play will have a better batting average (as determined by BABIP). Of course, this comes at the trade off of putting runners who are already on base at risk of the double play. “Batting Average” is too luck oriented (for the reasons mentioned above) to be “the” reliable input of OBP. If you want a higher BA-based OBP, you should look less to BA and more to a player’s K-rates (and BB%, although you probably don’t want to get rid of guaranteed-on base points (walks) in exchange for maybe-hits).

Thus, BA, though not entirely useless, is a misleading and inefficient metric by which to measure runs scoring ability. It’s a part of the equation, but it is a misnomer to point to batting average as a point of leverage in the equation. The best metrics which account for runs scoring are OBP (which encapsulates BA (which does account for 50-65% of OBP)), ISO, and K%.

this was all taken in part from:
http://gameofinches.blogspot.com/2010/01/quintessential-sabermetrics-argument.html

I actually thought of that H/PA thingy too for getting IsoD right, then realized we were just re-inventing the wheel.

Also, maybe I didn’t stress enough that these are both tools that should be used to separate players with similar batting averages. Clearly, it’s easier for a player that hits .300 to have a better OBP than one with .200 regardless of IsoD, and same with SLG/IsoP

We all know it’s not really joser.

Jack – I’m liking your stuff. Keep it up!