Spring Speaketh of Many More Dingers

It’s the annual exercise: Every year, right before the baseball that counts, there are six weeks of baseball that doesn’t count, but still many of us watch it closely. As we do so, we’re always trying to figure out which indications might be of something real, and which might be misleading. Predicting baseball is impossible work. Projecting baseball is near-impossible work. But we have just enough successes to keep doing it, each time trying to be better. At the end of the day, even when you get something wrong as you think about spring training, at least you’re thinking about baseball. That’s basically the point.

Study after study after study has shown that individual spring-training stats are unreliable. You know all the reasons why, and this is why the most interesting stuff usually has to do with, say, velocity changes. Hits, you can luck into. Higher velocity, you either can reach or you can’t. So we don’t talk all that often about spring-training statistics. Not on the player level, and not on the team level. But there’s a funny thing about league-wide numbers. There’s real signal in there. When you put all the spring numbers together, you really can get a glimpse of the future.

Spring training 2016 hasn’t wound completely down, but it’s just about there. What have we learned? Mostly, we’ve re-learned that spring training is too long. A few guys are showing velocity increases. A few other guys are showing velocity decreases. Everybody on the Dodgers is hurt. But let’s look at the league level, pulling spring numbers from MLB.com going back to 2006. Here’s a plot of spring walk rates, from 2006 – 2016, and of regular-season walk rates, from 2006 – 2015.


Pretty uninteresting, right? Over the past decade, there’s been excellent agreement here. There’s been an 8.1% spring-training walk rate, and an 8.2% regular-season walk rate. This spring, walks have gone up 0.4 percentage points, getting back to the 2013 level. If that happens in the regular season, it would be real and it would be observable, but this isn’t anything huge. Spring might be hinting at a very slight league increase in walks.

Now let’s look at the same plot, but for strikeouts instead:


The correlation here is almost perfect. Spring strikeouts are always below season strikeouts, for so many reasons, but the lines more or less mirror one another. Just as we’ve seen strikeouts skyrocket during the real baseball, we’ve seen them skyrocket in the exhibition baseball. This year, for the first time since 2008, we don’t see a spring strikeout-rate increase. Last year, during the season, strikeouts held at 20.4%. The rate rose to 19.8% in 2012, and since then it hasn’t budged very much. This could be the plateau. Alternatively, this could be a dispiriting false summit, to be explained by, I don’t know, something, but it could be this is about as high as we go. Perhaps strikeouts haven’t spiraled out of control — perhaps they’ve just spiraled to here. At this level, I think they’re still manageable.

So we’ll see where the strikeouts go. Now, lastly, we turn to home runs. In the second half of last season, league-wide homer rates spiked. I wrote about this for the most recent Hardball Times Annual, and just today, Rob Arthur and Ben Lindbergh wrote about it for FiveThirtyEight. They went so far as to have baseballs examined in a laboratory setting, but here’s your spoiler — there’s not yet any easy and full explanation. We don’t know why homers spiked. We just know they did. And, well, here’s another of those plots, this time showing home-run rates on contact:


Without question, this is more noisy than the previous two plots. It has to be, since there are just fewer homers than there are walks or strikeouts. That leaves this more prone to random variation, but with that being said, there’s still agreement in here, for the most part. You can observe similar trends, and after you notice that, you notice the point for 2016. That’s up at 3.99%. It’s easily the highest spring-training rate in recent history.

And it would be the highest regular-season rate in recent history. Which isn’t to say we know for sure how things are going to play out, but this does make you wonder. Between 2006 – 2015, we have 10 individual springs and 10 individual seasons. So, that’s 10 pairs. In nine of the 10 pairs, the regular-season rate of homers on contact was higher than the same rate in spring. Overall, we have an average spring rate of 3.32%, and an average season rate of 3.62%. What that suggests is that homers could stay up, moving forward. That’s what spring training has argued, and I don’t think this point could entirely disappear based on the outcomes of the final few days. Ordinarily, this might seem like a blip, but that’s what we said after last August, and then after last September. (And also after last October.) String enough blips together and they stop being so blippy. Baseball wants us to believe that we have home runs again.

I mentioned that, in nine of the pairs, the regular-season rate was higher. The one exception is 2013. That time, it’s like the spring rate spiked after the 2012 season rate spiked. The season rate subsequently dropped, and then it bottomed out in 2014. Maybe what we’ve seen this spring is just carryover from last year’s second half, and the season rate is going to fall. I swear, I don’t know. I doubt that even Major League Baseball knows. It was certainly caught off guard by the return of homers last summer. Sometimes numbers have a mind of their own.

But as we prepare for the regular season, we can say these things: Walks seem like they’ll be about the same. Strikeouts seem like they’ll be about the same. And homers look like they could be frequent. The spring suggests that last year’s second half wasn’t random. Sometimes the spring is a liar, but over big enough samples, it does prefer to tell the truth.

Jeff made Lookout Landing a thing, but he does not still write there about the Mariners. He does write here, sometimes about the Mariners, but usually not.

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6 years ago

More velocity means more strikeouts, but can it also means more homers?
If you make a mistake with a 99mph pitch, it might be easier for the batter to hit it stronger and further, right? Maybe the batter can’t square it as much as a 90mph pitch, but when they do it has more chance to leave the yard. That might be a reason for more homers

6 years ago
Reply to  borris_g

It’s been said that on average, an extra mile per hour on a fastball comes out to about an extra six feet of batted ball distance (something like that)

Lee Trocinskimember
6 years ago
Reply to  estone

It’s closer to 6 inches than to 6 feet. Alan Nathan has stated that 85% of exit velocity is created by the hitter, leaving the 15% to the pitcher. Increasing the pitch velocity by 1% means a 0.15% increase in exit velocity, which, in distance, would be less than one foot. This is an oversimplification, but just showing how little pitch speed affects batted ball distance.