The Triple-Slash Line Conundrum by Era

A couple of weeks in the past, I regressed as a writer. I regressed loads, really: twenty years price of slash line knowledge regressed towards twenty years of run scoring knowledge in varied methods. However — and this can be a harmful sentence, and often a nasty one — somebody requested me a query on Twitter and I need to reply it. Particularly: was batting common at all times the weakest correlation to run scoring among the many slash line statistics, or has it solely change into so lately?

That is going to be a fast hitter. I broke the sport down considerably arbitrarily, utilizing eras outlined by OOTP Perfect Team. I began in 1947 and went up till 2000 (the outcomes of the 2000s have been in my earlier article). Right here’s what these 2000s outcomes seem like, which ought to each offer you an concept of the correlations at present and preview the format for the remainder of the article:

With out additional ado, let’s get began.

Golden Years, 1947–1960
Now, these weren’t the golden years for me, as a result of I wasn’t alive, however I suppose that’s what some folks name this period of baseball. Jackie Robinson! Ted Williams! Stan Musial! Willie Mays! Batting common mattered extra, however it nonetheless didn’t matter:

What do I imply by that? Nicely, for those who predict run scoring with OBP and SLG, you get a 0.908 adjusted r-squared to precise runs scored. Predict run scoring with your complete triple slash line, and also you get an adjusted r-squred of 0.91. Batting common did higher, by itself, as a run scoring predictor, however utilizing OBP and SLG was the gold commonplace within the golden years.

Baseball Growth, 1961–1979
This can be a broad period that folds in some pitching-dominant years that led to guidelines modifications, the early a part of the velocity period, and a few early-60s residence run mania. It’s additionally an period the place, if you understand OBP and SLG, you don’t must know batting common to foretell run scoring:

Just like the 1947–60 span, utilizing OBP and SLG as predictors does simply in addition to utilizing all three statistics. Extra particularly, OBP/SLG had a 0.922 adjusted r-squared to runs scored. The total AVG/OBP/SLG regression checks in at 0.923. Common… for those who’re already 99.89% of the there, it’ll get you that final tiny little bit of explanatory energy. That’s not precisely a ringing endorsement.

Defensive Period, 1980–1992
Although I wasn’t alive for a giant chunk of this period and wasn’t following baseball for the overwhelming majority of it, it’s considered one of my favourite eras, due to Ozzie Smith, my single favourite baseball participant and, per my mother, the individual I’ve most emulated in my life. I spent numerous hours mimicking the defensive performs I noticed on my “Ozzie, That’s a Winner” VHS tape, which my uncle had recorded on native entry TV in St. Louis. I’m a lefty, so I used to be doing them backwards they usually by no means led to me turning into a defensive wunderkind, however none of that mattered to me; I simply wished to be like Ozzie. Uh, the place have been we? Oh, proper. Common didn’t matter:

Utilizing the standards from above, OBP/SLG checks in at 0.863, and an all-three-slash-stats regression checks in at 0.864. It’s attention-grabbing to notice that OBP and SLG clarify the bottom share of variation in run scoring on this period, which I attribute to the large vary in group baserunning technique and effectiveness, however that’s not the purpose of this research. The purpose is that for those who already know a group’s OBP and SLG, you don’t must know their batting common to foretell what number of runs they scored.

The Energy Years, 1993–2000
I minimize this one off at 2000, since my earlier article already coated the twenty first century, however OOTP extends it to 2004. Regardless, you guessed it:

This time, the adjusted r-squared is similar whether or not you have a look at OBP/SLG or AVG/OBP/SLG. So there you could have it: all through the eras, the correlations have remained the identical. In case you’re attempting to foretell a group’s run scoring and have already got their on-base share and slugging share, you’ll be able to cease there. Batting common received’t add something to the equation.