In our past two articles, we’ve discussed the importance of Contact Rate and Batting Average on Balls in Play (BABIP). Today, I’d like to talk about the third component of batting average and how you can put all three together to calculate batting average.

The third component is home run rate. There are other statistics we can use to arrive at this number (which we’ll discuss at a later date), but in the context of batting average, this is the simplest. It’s At-Bats per Home Run (AB/HR). It’s calculated, as you can imagine, by dividing at-bats by home runs.

You might not have thought that power has much to do with batting average. After all, a guy like Luis Castillo has a .294 career batting average while hitting 24 home runs in his career (which dates back to 1996).

Think about it, though. Contact rate measures the rate at which balls are either put into play or hit for home runs. BABIP measures the rate at which balls in play become hits. AB/HR measures the rate of non-balls in play, home runs. Home runs, while more damaging than a single, are still hits and therefore are included in batting average.

Hits divided by at-bats. Home runs are included among those hits.

I won’t go into the details yet of how we arrive at our AB/HR number (that’s more of a power discussion than a batting average one), but you can get a general sense of a hitter’s skill in this regard by looking at his history of AB/HR.

I’ve developed a very simple, intuitive tool in Excel to help you calculate batting averages easily. I think examining it will help shed a lot of light on this, so I ask that you download it now and look at it while reading. Scroll to the bottom of the post to download it.

Here is a screen shot of it:



Click on it to enlarge. In order to use the tool, all you have to input is what's highlighted in yellow: the hitter's At-Bats, Contact Rate, AB/HR, and BABIP. The tool does everything else.

And if you'll notice, everything matches up perfectly. Pujols did hit .327 last year with 32 home runs and 185 hits.

You can go through the formulas yourself, but I'll quickly explain how it works. When you input the ABs and Contact Rate, it simply multiplies the two together to get the number of contacted balls (BIP+HR). You then put in AB/HR, and it calculates HR by dividing AB by AB/HR. You then input BABIP, and it multiplies it by BIP (which it calculates by subtracting HR from BIP+ HR) to get Hits on Balls in Play (H on BIP). You then add this to HR to get your totals hits (H). You then divide hits by at-bats to get batting average!

Very simple, yet I'm sure a lot of you had never thought about batting average in this way before. All we're doing is taking the components of batting average and combining them!

Once you have the tool, you can fool around with numbers to see what guys would hit if they had different skills. Maybe you think Pujols was lucky with BABIP last year and you want to see what he would hit if his BABIP was just .300. Just input it into the sheet, and the calculations are done for you. You should get a .309 average with that BABIP adjustment.

I believe that this will be an invaluable tool to use not only when coming up with batting average projections in the off-season but during the season as well. Hanley Ramirez will not have a .600 BABIP all year and Mark Reynolds will not have a AB/HR of 6. Use this tool throughout the year to make adjustments and get an expectation for what a player should hit going forward.

If you have any questions about this, feel free to send me an e-mail!

Download the tool:
uploads/Component%20Batting%20Average%20Calculator.xls