Of Projections and Predictions

It’s February, finally, so spring training is just around the corner. Teams are putting the finishing touches on their rosters, filling out benches and bullpens, giving jobs to role players and evaluating the walking wounded. And now that the off-season is mostly finished, you should expect to be inundated with the buzzword of the month – projections.

CHONE. ZiPS. MARCEL. PECOTA. CAIRO. And yes, FANS. (Side note: are we capitalizing it, even though it’s not an acronym? I think we should. It’s not like anyone has any idea what CHONE stands for.) There will be no shortage of projection systems tossing out expected performances over the next month or two.

It won’t stop with just individual players, either. The guys over at Replacement Level Yankee Weblog have already run the CAIRO projections through the Diamond Mind simulator 100 times and posted the aggregate results as projected standings. Spoiler alert – the Yankees are good, the Blue Jays are not.

However, we need to make a distinction: projections are not predictions. Projections are information about what we think we currently know, while predictions are speculation about things that we probably cannot know.

This may sound like semantics, but there is an important difference here, and it’s often lost in the way projections are discussed. Too often, projections are treated as predictions of the future. You’ll see people say things like “CAIRO thinks the Blue Jays are going to only win 67 games this year,” for instance.

But that’s not really true. CAIRO thinks that the Blue Jays are on course to win 67 games, and if they don’t do something about it between now and the end of the season, that is their likely destination. But, like a map, the entire point of a projection is to inform the the user so that he can then alter the course if he so desires.

You would never look at a map and say “I’m traveling east on I-40. This map expects me to drive into the Atlantic Ocean.” The map just informs you that the course you are on will eventually lead to the ocean, and if you decide not to exit, wetness awaits. (Obviously, there’s some hyperbole here, as I realize that the freeway doesn’t end with a pier). The map has no expectation of what will happen. It’s just informing you of the course you are on.

Just like you control where you car goes, so do front offices control where their team goes, to a point. It is quite possible that Alex Anthopolous will look at his team’s internal projections and say, “Hey, we kinda suck; someone go find me a third baseman.” And then, after his assistants find him a third baseman, the team will be better. And people will say that the projection was wrong.

But it wasn’t wrong, because it wasn’t predicting anything. It was giving an evaluation of what was true at the time, to the best of its abilities. Its abilities may be flawed (and how you evaluate projection systems is another post for another day), but the intent was never to suggest what will happen, but rather, what could happen if nothing changes, knowing full well that things will change.

So, if you see a projection that you don’t particularly like, don’t get too bent out of shape about it. It’s just information about a path that a team may currently be on in February. By July, there’s a really good chance that the team will be on a different path, and a new projection accounting for that change in course will be available. Most of all, don’t assume that the people behind the projections hate your team. In fact, if your team gets a terrible projection, you may want to thank the system’s creator – that may just be the information that prods the front office to go out and improve the team, thus proving that the stupid system was wrong all along.





Dave is the Managing Editor of FanGraphs.

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Dan Lewis
14 years ago

*F*an *A*rrived *N*umbering *S*ystem