The Projections

As David announced this morning, the CHONE projections for 2009 are now available on the site. Sean Smith does great work with these, and they’ve been proven to be among the most accurate forecasting systems out there. Unlike the very bare bones Marcels (which are still quite good as a baseline), the CHONE projections include park effects and minor league data, which improve their accuracy a bit, especially for players where we have minimal major league data.

With that announcement, we now have three projections on each player’s page here on the site – Marcel, CHONE, and the Bill James projections from Baseball Info Solutions. One of the things that I’ve seen people do quite a bit is to take an average of the different projection systems available – especially Marcel and the James projections, since some feel Marcel is too pessimistic and James is too optimistic. However, the key is to understand the context of what each system is projecting. I figured today’s announcement would be a good starting point for a look at what I mean.

As an example, let’s take a look at Wladimir Balentien. He’s 24, has had success in the minors, but failed miserably in his first few hundred major league plate appearances last year. Here are the three forecasts for him for 2009 from the projections we have on the site:

Marcel: .239/.298/.402
CHONE: .231/.302/.409
James: .239/.312/.444

All three systems see a guy who isn’t going to hit for a high average due to his contact problems, but they vary a bit on how often he’ll draw a walk and how much power he’ll show. If you just look at the raw projections, you’d say that Marcel and CHONE aren’t big fans, but that the Bill James projections think he’s got some value. After all, it’s a 40 point OPS gap between James and CHONE.

However, take a look at this:

Marcel: 301 AB, -8.3 wRAA, -13.78 wRAA per 500 AB
CHONE: 472 AB, -6.3 wRAA, -6.67 wRAA per 500 AB
James: 426 AB, -6.6 wRAA, -7.74 wRAA per 500 AB

wRAA, of course, is the linear weights runs above (or in this case, below) a league average hitter. CHONE is actually more optimistic about Balentien than James’ projections. The entirity of the 40 point OPS difference is the projected level of offense in baseball next year. It has nothing to do with Balentien, and everything to do with what the various systems forecast as league average offense in 2009. Marcel is the one who really hates Balentien, but that’s to be expected, considering that the only data going in is his 2008 major league performance, while the other two factor in his minor league success.

You can’t look at just the BA/OBP/SLG numbers without adjusting for the projected context of that particular system. For whatever reason (my guess is that they’re not handling minor league translations very well and are overenthusiastic about young players, but that would take some more research to confirm), the Bill James projections always come out very high in forecast offense. The CHONE and Marcel projections usually match the upcoming year’s offensive level a bit better.

So, when looking at the various projection systems and the rate stats of the players, keep the environments that are being projected in mind. The value of a player isn’t in his rate stats, but in the value he provides above the baseline.





Dave is the Managing Editor of FanGraphs.

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colin
15 years ago

Can you guys include a league average wOBA somewhere for these then?