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The Fans Versus The Algorithms
Here on FanGraphs, we host several different projection systems, most of which are algorithms that take a player’s performance history and then mix in things like regression and aging curves to develop a forecast for 2013 production. But, we have one set of projections that is very different from the rest – the Fans Projections.
Instead of being based on any kind of mathematical model, these are simply crowdsourced from our readers, with you guys creating the projections with your various opinions about player performances for next year. While there are certainly some imperfections with any kind of crowdsourcing project, the widsom of the crowds has also shown to do pretty well in situations like this, and over the years we’ve done the Fans Projections, we’ve seen that the system actually holds its own when stacked up against the algorithms, though it does require one manual adjustments in order to make the system work properly: deflation.
Put simply, you guys are just too darn optimistic — I guess that’s why you’re called fans — and annually overproject total WAR by something like 20%. So, if you look at the data from the Fans Projections next to something like ZIPS or Steamer, you’ll see some huge discrepancies, but a lot of those simply have to do with the scale, and once the Fans Projections are deflated to create a more accurate overall total, many of the variances go away.
Not all of them, though. There’s one clear type of player where the Fans and the algorithms disagree, and it’s probably a telling area, given what we know about the fine line between hope irrational exuberance. That type of player? Prospects.
The Differences Between Predictions and Projections
In my Monday post about the White Sox recent success beating preseason projections, I included a statement that I’ve mentioned a few times over the last few years:
But also, please just keep in mind that projections are not predictions. They are a snapshot of what we think a team’s median true talent level might be, and it should be understood that there’s a pretty sizable margin for error based on things that projection systems simply can’t forecast, and also the errors that come from having imperfect information or imperfect calculations.
I wrote about this distinction a couple of years ago, but I think it’s worth delving into the differences again. For one, FanGraphs has gotten a lot larger over the last few years, so many of you might not have read that piece, but also, I think there’s a few things that I could have stated better in that article, and I want to give more context for why I see the distinction as meaningful rather than being a semantical argument with no practical use.
Let’s start out by acknowledging that predictions are a subset of projections. Or, to put it another way, predictions are projections, but a projection isn’t necessarily a prediction. I know that’s a bit of a tongue twister, and seems like a semantical difference, but think of it like this: Mothers are women, but not all women are mothers. No one would suggest that it is simply semantics to clarify whether a women is or is not a mother. There’s a meaningful difference there.
Diamondbacks Acquire Tony Campana’s Base Stealing
The Arizona Diamondbacks outfield roulette continued today, as they announced they’d shipped a pair of low level minor leaguers to Chicago in exchange for Tony Campana. Yes, the Diamondbacks just traded for another outfielder, despite the fact that their OF is already one of the most crowded in baseball. With Adam Eaton and Gerardo Parra in the fold, it doesn’t seem entirely clear why Kevin Towers felt that the organization needed another speed-and-defense center fielder.
What is clear, though, is that Campana can help a big league team even though he can’t hit. In fact, Campana might be one of the most interesting bench players in baseball.
The White Sox and Beating Projections
There are a lot of projection systems floating around the nerdy baseball universe. Here on FanGraphs, we host a lot of them, including ZIPS, Steamer, Oliver, Marcel, and the Fans projections, and then there’s other systems like CAIRO and PECOTA that are hosted elsewhere. Of all the baseball projection systems, PECOTA is probably the most famous because it was created by Nate Silver, and Nate Silver is now pretty famous for his post-baseball career. So, when PECOTA releases their annual projections, mainstream writers pay attention. And Chicago writers, particularly, like to talk about PECOTA’s projections, mainly to remind everyone how wrong they’ve been about the White Sox.
For instance, here’s a piece by a local radio anchor that trots out all the usual ad hominem attacks about geeks and their numbers. And here’s another one of this year’s entries, which just gives up on factual information completely:
What is it about the White Sox’s rosters and farm system that Baseball Prospectus doesn’t like?
To answer that question, I decided to do research on who writes these inaccuracies year after year. What I found shocked and disturbed me.
It’s Nate Silver.
My whole world of reality collapsed at that moment.
How could it be the guy I religiously read for pinpoint accuracy in politics? How could it be that Silver is an accuracy genius in politics, but yet when it comes to the White Sox he transforms into the accuracy of a Republican pollster?
After composing myself, I discovered a possible reason. Silver lived in Chicago for many years near Wrigleyville and is rumored to be a Cubs fan.
Maybe being a Cubs fan is a weighted bias even Silver’s methodology can’t overcome.
I’m not here to defend PECOTA — BP can do that if they’d like — but I will just insert some facts into the discussion. Like, for instance, that Silver grew up in Michigan as a Tigers fan, not a Cubs fan. Or, that Silver hasn’t been in charge of the system since 2009, and the code has been essentially rewritten since he left. And, of course, it would be remarkably silly for any forecaster to create a system that intentionally downgrades the projections of a specific franchise, since that would simply make the system less accurate and hurt his own credibility. The idea that PECOTA has some kind of anti-White Sox bias because Silver went to the University of Chicago and attended some Cubs games is worthy of the tin foil hat brigade.
That said, I do think it’s interesting that the White Sox have regularly outperformed PECOTA’s expectations, and I think it’s worth actually investigating, as opposed to what Michael Tomaso did. So, let’s investigate the White Sox overall performance since 2005.
A Walk Through The Early Over/Unders
We’re still six weeks from opening day, but the first sports book over/unders were released the other day, and while this is not an endorsement of gambling, it can be fun and informative to look at how the Vegas proprietors see each team stacking up before the season. So, let’s take a look at the early numbers.
The Rise of the John Lackey Clause
When the Red Sox signed John Lackey as a free agent in December of 2009, they had some concern about an existing elbow injury, but not enough concern to walk away from the deal entirely. So, they (or maybe his agent) came up with a pretty creative solution, adding a league minimum club option to the end of the deal if Lackey missed significant time due to an elbow issue. Sure enough, Lackey’s elbow became problematic, and after the 2011 season, he underwent Tommy John surgery and spent the entire 2012 season on the DL, triggering the club option for 2015.
As a result, the Red Sox now own the rights to Lackey’s 2015 season at a salary of around $500,000. Given the recovery rates of Tommy John survivors, it’s quite possible that Lackey could still be a useful pitcher in a couple of years, even at 36-years-old. If he rebounds and becomes something like an average starting pitcher, that option could end up holding $10 to $15 million in value, which wouldn’t quite make up for the fact that the Red Sox paid Lackey $15.25 million to spend last year rehabbing, but it would certainly help balance the scales.
Well, it seems like that contract stipulation might be gaining in popularity. Yesterday, Felix Hernandez signed his seven year, $175 million contract with the Mariners, and it included a stipulation that might very well come to be known as The John Lackey clause.