David Appelman is the creator of FanGraphs.

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Bob M
12 years ago

# of guys forcasted to have more than 30 home runs:
Steamer: 14
ZiPS: 12
Marcel: 2

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Eric
12 years ago
Reply to  Bob M

It also has no one receiving more than 600ABs.

Use rate stats.

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Yirmiyahu
12 years ago
Reply to  Eric

And there’s a very good explanation for that. Look at the most durable position players from 2008-2010. 51 guys had 1800+ plate appearances (600+ PA’s a season). That group averaged 651 PA’s over those 3 seasons. However, those same 51 players averaged 558 plate appearances in 2011. That’s about a 15% drop in playing time. Blame Joe Mauer, Stephen Drew, Hanley Ramirez, David Wright, Chase Utley, Adam Dunn, etc.

The other forecasting systems will assume that everyone will continue to be healthy and get playing time. But they’re going to be very very wrong about a handful of guys who unexpectedly get injured or have an unforeseen decline.

Marcel just assumes that everyone has an equally small chance of having a fluke injury, and factors that into its playing time projections. Marcel is not saying that no one in baseball is going to get 600 AB’s. It’s just hedging its bets. And despite the fact that its run by a monkey, it’s right to do so.

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Tangotiger
12 years ago
Reply to  Eric

Great job Yirmiyahu!

I don’t know how much Marcel forecasted for those guys, but it would have been somewhere between 550-600 PA.

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Baltar
12 years ago
Reply to  Bob M

Marcel is not forecasting that exactly 2 players will hit over 30 HR’s.
The system forecasts what you might call a “medium” performance for each player. Out of perhaps a few dozen players forecast to have 20-25 homers, maybe a dozen or so will hit over 30, a dozen or so less than 15.

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Yirmiyahu
12 years ago
Reply to  Baltar

Exactly. Its usually folly to make extreme predictions. Sure, maybe 20 players a season will have 30 HR’s or 100 RBI’s or 15 Wins or an AVG over .300 or an ERA under 3.20. But its very difficult to project which individuals will reach those milestones.

Over the last 2 seasons, ZiPS projected 28 guys to hit 30+ homers, but only 17 of those projected reached the milestone. On the other hand, Marcel only projected 16 guys to hit 30+ homers, but it was “correct” on 13 of them.

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Tangotiger
12 years ago
Reply to  Baltar

Great job Yirmiyahu !

Is it better to be right 13 on 16, or to be right 17 on 28? Or even say just 3 for 3 (as I presume someone could have made it really really conservative)?

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EnricoPalazzo
12 years ago
Reply to  Bob M

Good point. 2011 was a pitcher-dominant year and yet 20 players got over 30 home runs.

0