Stats to Avoid: Batting Average
Batting average is the most recognizable statistic in the game. It might be the most famous statistic in sports and it’s probably up there with Gross Domestic Product (GDP) among the most popular statistics about anything anywhere on the planet. Even people who don’t like or watch baseball understand what batting average means. Just like how you know a singer is famous because your mother knows who they are, you know batting average is huge because you never have to explain it to anyone.
Which is why it’s so difficult to remove it from our vernacular. Batting average is built into the language of the sport, but it’s simply not a useful statistic and if you want to analyze a player properly, it’s something you don’t want to pay close attention to at all.
There are a myriad of other options ranging from OBP to wRC+ that you can use instead, but this post is going to lay out the case against batting average and why you should look for a new go-to statistic this season. If you want to read up on your other options, we have tons of pages and articles that explain them.
Batting average has two primary flaws that we’ll address in turn. First, batting average ignores a segment of offensive actions just because they aren’t “hits,” and 100 years ago, someone decided a hit and a walk were fundamentally different.
But in reality, the difference is among players with similar batting averages but much different walk rates. If you come to the plate 450 times and get 150 hits and no walks, you have a .333 batting average and a .333 on-base percentage. If you come to the plate 500 times and get 150 hits and 50 walks, you have a .333 batting average and a .400 on-base percentage. Those are vastly different hitters but batting average isn’t sophisticated enough to account for the difference.
In baseball, we care about run scoring (and prevention) and so when looking at offensive statistics, we want to find statistics that tell you something about how much a player contributes to the run scoring process. Batting average leaves out walks and walks play a major role in run scoring.
The second major flaw is that batting average treats every hit equally even though certain hits are more valuable than others. Batting average treats a single and a double like the same thing, even though a hitter who only hit doubles would help his team score a lot more runs than a hitter who only hit singles. Again, we care about a player’s contribution to run scoring and if you treat everything equally you’re not getting a very accurate measure of those contributions.
Which leads us to pose the question, what does batting average bring to the table? When thinking about a statistic, you need to consider what question it answers and if you want to know the answer to that question at all. Batting average tells you how many hits a player gets per at bat.
And is that something you care to know? Really think about it. If there were no baseball statistics and it was your job to create them, would you want to separate out hits and at bats from times on base and plate appearances? What does batting average tell you that OBP doesn’t? Does it tell you anything you can’t learn from wOBA?
In general, the answer is no. You might want to get a sense of the type of a hitter someone is by comparing their AVG, OBP, SLG, wOBA, etc, but you wouldn’t ever want to judge a player based entirely on his batting average. It’s simply not communicating anything very important.
It’s worth making an important distinction, however. Batting average tells you something about how good a hitter has been, it just doesn’t tell you as much as other available statistics. A .360 batting average is a pretty strong indicator that you’re looking at a successful offensive player and a .205 batting average probably means the player is lousy. The point isn’t that batting average tells you nothing, it’s that it tells you much less than OBP, OPS, wOBA, or wRC+.
In other words, there’s nothing batting average tells you that you can’t learn somewhere else while also learning even more. So in the end, it’s not that batting average is useless, it’s that it’s only useful if you don’t have access to these other statistics. You can butter a roll with a spoon but there’s no reason to use a spoon if you have easy access to a knife.
Analysts have left batting average behind in favor of OBP, wOBA, and wRC+ but it’s still part of the conversation among fans and on broadcasts. That’s slowly starting to change, but there’s still a long way to go before it’s completely left the discussion. As you prepare for the 2015 season, I encourage you to look into some of the other offensive rate statistics and make them a part of your repertoire.
Neil Weinberg is the Site Educator at FanGraphs and can be found writing enthusiastically about the Detroit Tigers at New English D. Follow and interact with him on Twitter @NeilWeinberg44.
“If you come to the plate 500 times and get 150 hits and 50 walks, you have a .300 batting average and a .400 on-base percentage.”
#actually, you’ll have a .333 batting average. But yeah, obviously that still helps to illustrate the point that batting average is ostensibly “the percentage of times a player gets a hit” but fails at even measuring that.
150 hits in 500 P.A. is a .300 avg bud
Average = Hits / At Bats. …. A walk doesn’t count as an “At Bat” so you need to subtract the 50 walks first… so it’s 150 / 450 = .333
Batting average uses AB as the denominator, rather than the more inclusive PA, so unless you know the breakdown of how many appearances fell into the buckets of outcomes that don’t count as “at-bats”, you can’t even determine the batting average with just that data.
If there were no walks, no HBP, no sac flies or sac bunts, and so on, then that would indeed be a .300 BA, but going 500 PA without a single one of those outcomes is extremely unlikely, so the actual figure will probably be a bit higher (and still not as useful as the OBP figure).
Stepping up to the plate 500 times is different than having 500 at bats