Category: Math

Remember many days ago when we talked about how pesky it is to have a ball in play? That’s as true for pitchers as it is for hitters. So, some enterprising folks struck out to roughly measure ERA in a way that ignores balls put in play, instead focusing entirely on the Three True Outcomes. Fielding Independent Pitching (FIP) is a defense-agnostic statistic to compare against ERA, and in some ways is an ideal “predictor” statistic for ERA.

That’s right, the “+” statistics exist in the realm of pitching. Park adjustments and a percentage normalization is a natural extension of ERA, and makes it more meaningful for directly comparing pitchers, even across generations.

While ERA is a measure of overall pitcher effectiveness, there’s a more nuanced statistic that considers how frequently a pitcher allows runners on base. Walks and Hits per Inning Pitched (WHIP) is easy to calculate, has a cool acronym, and is another factor to consider when measuring how good a pitcher is at keeping hitters from doing their jobs.

Let us leave the world of sluggers and slap-hitters behind us, and move 60 feet forward to the pitcher’s mound. I’ve always enjoyed and valued pitching over hitting in my baseball life. As such, the first ten days of hitting required me to learn more than I anticipated, while I feel more prepared to handle this section of Blogmas.¹I’m still doing my research to make sure I have everything correct. We’re not starting as simple as possible, but we are starting with the most important of the original pitching statistics: how good are you at preventing runs from scoring?

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  I’m still doing my research to make sure I have everything correct.

Today we move onto one of the gems of advanced baseball statistics¹Somehow I’ve gone this long without using the phrase Sabermetrics, which is the catch-all term for many of the derived values we’ve been covering. Its name comes from SABR, the Society for American Baseball Research. that generalizes player value beyond concrete elements like hits and runs, and looks specifically at how many wins a player is worth.

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  Somehow I’ve gone this long without using the phrase Sabermetrics, which is the catch-all term for many of the derived values we’ve been covering. Its name comes from SABR, the Society for American Baseball Research.

Let’s dive back into the weeds. Hitting the ball and getting on base are important jobs for hitters. But what actually wins the game? Scoring more runs than the other team. Today, we’ll look at two ways of quantifying run production, both of which are weighted in the same way we saw with wOBA.

Today we’ll look at a statistic that is interesting for both the offensive and defensive side of baseball. When a ball is put in play, how often does it go for a hit?

In another day of simpler statistics, Isolated Power (ISO) is derived from slugging percentage. It’s calculated in the exact same way, but ignores singles. Hence, it is isolating the power of a hitter, defined as the rate at which they get extra-base hits.