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  1. What are these Marcel predictions? How exactly do they work? Because every single player; let me repeat that: every single player I looked up is predicted to have a worse year in most categories by Marcel. For example, Ryan Howard is expected to hit 40 homeruns. He’s not yet 30 and has hit at least 47 homeruns in each of the last 3 seasons. How by any stretch is he expected to hit only 40 unless he becomes injured? Even young players where improvement should be expected are projected to have worse years. It makes no sense to me.

    Comment by Jim — November 18, 2008 @ 12:37 pm

  2. Yovani Gallardo, who is good to go for next season and was hampered by a freak accident last season, is expected to pitch 92 innings. What gives?

    Comment by Jim — November 18, 2008 @ 12:38 pm

  3. Marcel has Jason Bay hitting .269 with 24 homeruns in the heart of the Red Sox lineup….I’m inclined to just completely disregard these projections because I think most of them are misleadingly conservative.

    Comment by Jim — November 18, 2008 @ 12:42 pm

  4. The Marcel system is, like every other projection system, based on regression analysis. It uses the player’s last three seasons, weighting the most recent more heavily, and attempts to determine their true talent level based on their prior performances. It then applies an aging curve to project future performance.

    The concept of regression to the mean is an important one to grasp in understanding projections. I’d suggest looking over some articles about regression and how it applies to projections.

    To read more about the Marcels, how they work, and how accurate they are (short answer – pretty much as good as even the more complicated systems), start here.

    Comment by Dave Cameron — November 18, 2008 @ 12:46 pm

  5. Jim: “It uses 3 years of MLB data, with the most recent data weighted heavier. It regresses towards the mean. And it has an age factor.”

    They are barebones projections and should be the least accurate of all the systems (even though there are sometimes other systems that have been less accurate).

    You can read more about them here: http://www.tangotiger.net/marcel/

    Comment by David Appelman — November 18, 2008 @ 12:47 pm

  6. Please read this article so that you have a better understanding of why the forecasts work, in general (click my name).

    Also, Marcel pays no attention to the name, injuries, or minor league stats. Even Barry Bonds is given a forecast.

    You may be inclined to disregard, but please read the above article first before doing so.

    Comment by TangoTiger — November 18, 2008 @ 1:12 pm

  7. Ok thanks for the info. I’ll check those links out.

    Comment by Jim — November 18, 2008 @ 2:53 pm

  8. Marcel has Jason Bay hitting .269 with 24 homeruns in the heart of the Red Sox lineup….I’m inclined to just completely disregard these projections because I think most of them are misleadingly conservative.

    I’m confused as to how hitting in the heart of the Red Sox order would increase home runs or batting average. Care to share the logic on that one?

    Comment by Sal Paradise — November 18, 2008 @ 10:33 pm

  9. I just read the tangotiger article and the explanation of how guys who common sense says will hit more homeruns are projected to only hit 25 or so: Because that is what the group of similar players will average out to hit? How does that help anyone? There might as well not be any individual projections….

    Comment by Jim — November 19, 2008 @ 12:58 pm

  10. I prefer conservative projections, I tend to get let down less often. :)

    Comment by JWay — November 19, 2008 @ 1:44 pm

  11. After reading through the link given in the article again, it seems to agree with me that individual projections are rather pointless. I mean they’re fun and all, but why not just stick with the type of format used in the explanation?

    Comment by Jim — November 19, 2008 @ 4:59 pm

  12. Individual forecasts are completely pointless, if you are looking for a forecast of how many HR a power hitter will hit, +/- 10% HR, 95% of the time. But, if you are looking for +/- 30% HR, 90% of the time, now we’re talking!

    At the exact same time, single-game forecasts as to who will win are similarly pointless. If one team has a 52% chance of winning, then guess what: it’s not 100%. It’s 52%.

    While individual player forecasts are completely pointless under the +/- 10% standard, then are very valuable at the group or team level under the same +/- 10% standard.

    Caveat emptor.

    Comment by TangoTiger — November 20, 2008 @ 11:56 am

  13. Is it possible to put the projections on the team pages. For example, you have a drop down for each year. Can you add 2009 (projected Marcel) to that drop down?

    Comment by Andrew — November 25, 2008 @ 11:38 pm

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