07 February 2015

Statheads Have To Lighten Up About Their Projections

When a kid gets a shiny new toy he always wanted for Christmas, it's not surprising that he plays with it endlessly. And when it ceases to work, it's not surprising that he puts it away.

The seamheads turned out shiny new projection toys in the 2000s variously called PECOTA, Steamer, ZiPS, Marcel, FANS and Oliver, depending on whose proprietary system you prefer. (For example, Baseball Prospectus created PECOTA, Fangraphs introduced ZiPS and Tom Tango developed Marcel.) They all compare ballplayers of today to their counterparts in history to determine what awaits the current crop in the coming year. All that is then compiled into team projections.

These toys have some value for a couple of reasons: they are objective and they have built into them some simple rules that humans fail to recognize or choose to ignore when analyzing player performance. Beyond that, though, they offer little insight. Most significantly, they don't know anything about the people who play the game. They are blind to who learned a new pitch, is struggling through a wrenching divorce, picked up a hitch in his swing or is finally healthy.

As a result, they can never tell us who will suddenly break out, Jose Bautista style, or who will Dontrelle Willis all over himself. None of them could pinpoint the 2014 demise of the Red Sox or the Orioles' pre-eminence. And yet the sabermetric world talks about these tools as if they're atom splitters.

So, for example, Steamer predicts the top 10 players by WAR next year are Mike Trout, Andrew McCutcheon, Giancarlo Stanton, Troy Tulowitzki, Miguel Cabrera, Josh Donaldson, Evan Longoria, Adrian Beltre, Jose Bautista and Paul Goldschmidt. (Cano, Machado and Puig are right behind.) Well, duh. right? (Clayton Kershaw and Felix Hernandez are its top pitchers. Who knew?)

It says Joey Votto and Bryce Harper are stars with injury risks. You don't say. It projects Chris Davis bouncing about halfway back to 2013 with a .242 batting average and 30 home runs. About what you'd predict. It sees Justin Verlander returning to about league average pitching. And it's not really buying Rookie of the Year Jacob deGrom. Well, who outside of the outer boroughs is?

So the toys have some entertainment value, but the saber community plays with them as if they're iPads.  They quote chapter and verse on players, particularly when analyzing trades and signings. The truth is, exercise a few simple guiding principles, like Warren Buffet investor tips, and you too can lord over the average baseball fan.

And be right 60% of the time.

In subsequent posts, we'll discuss those principles, examine some interesting player projections and the swim among the team projections. (Spoiler alert: the Phillies will suck.)


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