On Saturday, when describing Steamer’s methodology at Saber Seminar, Dash presented the following graph:
Here are the twenty “most improved” batters of the 2012 season:
The folks here at Steamer Projections will be at Saber Seminar:
Warning: What follows is a ridiculously Steamer-centric guide to your fantasy baseball preparation this year.
We’ve updated our playing time projections and posted new sheets. The new downloads include a number of players who were missing from our initial forecasts including Yu Darvish.
As we get ready to revisit Steamer’s 2012 playing time projections, I thought I should take a look at which systems had the most success projecting playing time last year. Many thanks to Rudy Gamble of Razzball and Mike Spiher of Rotochamp who made this possible by supplying the data. Continue reading
Update: Thanks to Brian Jenner we now have .csv files for Last Player Picked tailored to the ESPN and Yahoo! position eligibility.
Update: Here’s Nate Silver’s thoughtful analysis of accuracy of his projections from last week. Nate also points out that the errors aren’t necessary normally or even symmetrically distributed as I assumed in the analysis below.
On his fivethirtyeight blog, Nate Silver has made 55 projections for 2012 Republican Primaries, each one including a projected mean and a 90% confidence interval.
Earlier in the primary season, Tom Tango pointed out that Nate was too accurate, meaning that his error bars had been wider than needed to that point.
Now that there’s more data, I’ll revisit the question: Are Nate’s confidence intervals too wide? Too narrow?
It turns out that 50 of his 55 projections (darn close to 90%) are within his 90% confidence intervals. Of course, the errors are correlated. For instance, if you were too bullish on Ron Paul in Virginia it implies that you were too pessimistic about Mitt Romney. To get a better sense of the distribution of Nate Silver’s misses I followed Tango’s lead and calculated a z-score for each of his predictions. Here’s a histogram showing the distribution of the z-scores:
This looks fairly reasonable. You can see the two largest misses from Massachusetts and Virginia at the extremes.
So, how accurate is Nate Silver? Quite possibly, just as accurate as he says he is.
Download the data set used in the above analysis:
Nate Silver 2012 Primary Forecasts (212).
Right now, we’re hedging our bets on Chris Sale, projecting that 29% of his innings come in relief. We have him throwing 129 IP with a 3.60 ERA, 9 wins and 15 holds. In this role he generates an impressive 9.8 K/9 with his 94.5 mph fastball. This line give him $9.30 of fantasy value making him our 72nd ranked pitcher.
But what if you don’t think Sale will make the rotation?
We give Sale 64 IP as a set-up man, Steamer forecasts a 3.34 ERA, a superb 10.5 K/9 and a fastball averaging 95 mph. Unfortunately, even with a handful of saves this line only provides $3.00 of fantasy value, making him roughly the 112th best pitcher available.
And if we let him face 850 batters over 30 starts and 200 innings? His strikeout rate falls to 9.5 K/9 and his ERA ticks up a bit to 3.74. He also wins 13 games, however, and throws his fastball at 94.3 mph. This makes him a $15.60 player, 22nd in our pitcher rankings.
Of course, Steamer doesn’t know how well his fastball will hold up over a full season and doesn’t know about his excellent changeup. But, based on what it does know, Steamer is bullish on Mr. Sale.
Update: Version 3.0 of the pitcher projections is out. We adjusted Steamer to account for the lower run environment over the last couple of years.
The 2012 Steamer Hitter Projections are now available for download.
We’ve also uploaded version 2.0 of our pitcher projections. This version includes the projected fastball velocities that Steamer uses in its pitcher forecasts. For pitchers with prior MLB experience we generated these numbers using pitch f/x data from Fangraphs and Peter deserves a great deal of credit for laboriously typing in fastball velocities from the 2012 Minor League Baseball Analyst for the guys who haven’t yet made it to the show.
Enjoy and thanks in advance for your input!
