Archive for September, 2015

Two Different Ways To Be Wrong: Sequencing and Bad Projections

Baseball analysts are frequently wrong. Everyone who writes for this website picked the Nationals to win the NL East, for example. We also split between Detroit and Cleveland for the AL Central, with no votes for the Royals. Predicting baseball is difficult because it’s a game with many variables and lots of randomness. It is probably very unlikely that a world class chess player would lose to a novice in any one game, but it’s especially unlikely they’d lose more often than not over 100 games. In baseball, there are so many things impacting single games, and there are 2,430 games, so predicting a full season is especially challenging.

And as has been noted in a lot of places, we didn’t do a great job predicting the 2015 season. The Rangers, Astros, Blue Jays, Royals, and Mets weren’t exactly consensus playoff picks. Whoops!

This has led to plenty of push back against sites like ours and serves as a criticism of the work we do when it comes to predicting the game. Presumably, if we can’t accurately predict which teams will be good and bad, you might not want to put a ton of stock in what we’re saying. Surely, no reasonable person would hold anyone to a standard of perfection, but whiffing often can be a sign of a flawed process.

I’m not going to litigate exactly where our projections may or not be flawed in this post, but rather, I want to separate out two very different components of overall wrongness. In fact, there are essentially two ways in which our overall estimates of the league can be incorrect and you should understand the forces at play when determining how much stock to put into the work done here, and at other sites like Baseball Prospectus.

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The Beginner’s Guide To Pulling A Starting Pitcher

Unfortunately, if you are a major league front office employee, this is not a presentation of ground-breaking new research regarding the prediction of pitcher meltdowns that will save you innumerable frustrations. Rather, this post provides a summary of some of the basic factors that go into the decision to pull a starting pitcher. If you’re new to the game or are just starting to pay attention to sabermetrics, it’s likely that you haven’t really ever had a run down of the different decisions a manager needs to make when plotting out their mid- to late-inning choices.

The conventional wisdom is generally about two things, fatigue (usually in terms of pitch count) and effectiveness (usually in terms of a stat line or recent hitter performance). A pitcher will get yanked after 100-115 pitches unless they are absolutely dealing or a pitcher will get yanked if they’re getting hit around a lot. Over the first seven or eight innings, that’s typically the mindset of many. Of course, there’s the obnoxious “save situation” problem that arises in the ninth inning, but we’ll leave that for another day.

But in general, while fatigue and effectiveness are good variables, the decision to pull a starting pitcher is multi-dimensional. Let’s consider some of the factors in more depth.

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