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  1. Interesting…thanks for the info!

    Comment by Tyler — February 15, 2011 @ 12:15 pm

  2. ESPN is the best pitcher forecasting system? Are you sure there isn’t some sort of weird selection bias here? How do you determine the player pools that you assess?

    By the way, it seems incorrect to me to assess different pools for different systems. You have to pick a player pool and see how each system does with that pool. Then the problem becomes “what do you do with players that a system doesn’t project?” If CBS and ESPN aren’t projecting certain players, I’m worried that they’re getting an unfair edge because the players they aren’t projecting are the hardest to project.

    Comment by philosofool — February 15, 2011 @ 8:01 pm

  3. @philo: I was pretty surprised myself. ESPN is the best? Really??

    You’re absolutely right that you can’t consider different pools of players and then try to compare the metrics. That’s why the pitchers I consider are those with forecasts from each projection system, so the player pool is the same for each metric (146 pitchers total). Hopefully this eliminates any selection bias across different projection systems.

    Comment by Will Larson — February 16, 2011 @ 8:03 am

  4. Nice, I’ve been looking forward to your pitching weights. Since reading your hitting articles I’ve began compiling a simple average between MARCEL, FANS, ESPN, RotoChamps, CAIRO, and Bill James (ESPN.csv from your site). It looks like I’ll be dropping the mechanical forecasts for pitching thanks to this latest finding. I decided to exclude CBS since their excel format for names was {last name, first name} and unlike all others. Is there any way to get around this? I’ve been using averageif in excel to compile averages to one sheet. One final note: In the comments of your last hitters forecast article you mentioned you’d be posting the weighted projections on your site. Any idea when that will be?

    Comment by Half Full — February 17, 2011 @ 1:30 am

  5. I like the idea here, and appreciate the work. But the forward-looking conclusions simply aren’t supported by looking at a single year of data. To say, “If someone had the Fangraphs Fans, ESPN, and CBS forecasts, they couldn’t add any value by adding one of the mechanical forecasts.” and “1) ESPN is really good at predicting pitcher performance. 2) Mechanical forecasts are bad at predicting pitcher performance,”
    is just reckless. You can say in the past tense that systems X,Y and Z provided no value over the competition in 2010; but in the grand scheme of things, this is a very small sample, and certainly not enough to declare the future value of any system.

    Comment by evo34 — February 17, 2011 @ 2:33 am

  6. @Half Full: Wow, I didn’t realize anyone was looking at that yet. It’s still in development, and I haven’t put all the forecasts up there yet. I’ve finished my hitter forecasts for next year and am working on the pitchers. They should be up next week sometime. At that point, I’ll write something up for Fangraphs and hopefully they’ll give me some press. For those of you who don’t know what I’m talking about, go to http://www.williamlarson.com/projections

    As for your excel issue, go to tools->text to columns, then choose “,” as the delimiter. Can you email me the CAIRO, CBS and RotoChamps forecasts so I can put them on my site? I haven’t had the time to get them yet.

    @evo34: You’re absolutely right that these are backward looking, but past optimal forecast weights have performed well in other areas, and so I think they might have some use going forward. This article isn’t the end of the analysis. For next year, I’ll compute forecasts based on these weights to see if they outperform individual forecasts, a simple average, and see if the “optimal weights” change. Thanks for the comment!

    Comment by Will Larson — February 17, 2011 @ 1:51 pm

  7. @Will No problem, I can put those together for you. I’ll try submitting them through your website. RotoChamp projections are available on the FanGraphs projection page already if you hadn’t noticed.

    Comment by Half Full — February 17, 2011 @ 4:12 pm

  8. Just to clarify – this only means ESPN did the best in 2010, correct? So they could be worse than the others, but in the year of the pitcher happened to have guessed pitchers the best?

    Comment by Wade8813 — February 20, 2011 @ 7:47 am

  9. @Wade: Yes, you’re right. I’m only looking at 2010. I’ll need to look at other years to see if ESPN consistently outperforms the others or not. That being said, in other areas where people look at these weighted-average forecasts, the weights tend to be correlated from period to period.

    Comment by Will Larson — February 21, 2011 @ 1:03 am

  10. Will, did you graduate? Wondering what happened to your intriguing 2011 projection comparisons..

    Comment by Joel — February 17, 2012 @ 2:57 pm

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