Study: Steroids Enhanced Performance for Mitchell Report Players
J.C. Bradbury at Sabernomics points to a new study concluding that baseball players named in the Mitchell Report got a little production boost from using performance enhancing drugs.
Compared to the average player between the 1995 and 2007 seasons, Mitchell Report players got a performance bump of between 7 and 12 percent in the seasons that they were identified as using steroids, write Brian Schmotzer, Jeff Switchenko, and Patrick Kilgo of Emory University's School of Public Health in the study published in the Journal of Quantitative Analysis in Sports.
The effect was limited to those players who were I.D.'ed as using steroids. Exclusive use of human growth hormones had no positive impact on a player's output, a conclusion also reached in this study.
However, there is a silent elephant in the room in the name of Barry Bonds, says Bradbury. When he is kept out of the dataset, the correlation between being named in the Mitchell Report and improved performance disappears.
On the other hand, when the researchers included Bonds they only identified his 2003-04 seasons as steroid-use seasons. According to the statistic used to measure performance in the paper, runs created, the '03 and '04 seasons were Bonds' 3rd and 5th-best, respectively. Under this scenario, the link between steroids and performance for the average player was significant and came out to about 7 percent.
Two other studies have been conducted using data from the Mitchell Report. This one by statisticians at Cornell and the University of Chicago found no evidence of a steroids boost while this one by Milwuakee's Journal Sentinel found that more than half of the 90 players identified in the Mitchell Report played better in the two years after juicing. (This latter finding has also been criticized.)
Relatedly, after the first month-and-a-half of this season, there wastalk that the Steroids Era was over because offensive production had fallen off considerably.
Now that we're more than 75 percent of the way into the season, it looks like there's been some reversion to the mean. Although the slugging percentage for the entire league is at its lowest level since 1995, it's only two points below its previous low of 0.417 percent in 2002:
- Should the Fed Go Long?
- Dec 1 2008 4:38PM EST
- Bernanke's Speech
- Dec 1 2008 2:58PM EST
- Even Nobel Economists Can Be Intellectually Dishonest
- Nov 30 2008 9:36AM EST
- A 5-Point Plan for Getting Out of This
- Nov 28 2008 1:24PM EST
- Do Markets Filter Irrationality?
- Nov 26 2008 11:25PM EST
- Are Percentages Really That Hard?
- Nov 26 2008 10:07PM EST
- Chart of the Day
- Nov 25 2008 3:27PM EST
- Highlights of the Citi Bailout
- Nov 24 2008 12:29AM EST
- 24 Hours in the Stock Markets
- Nov 23 2008 6:44PM EST
- Bloomberg Not Shy About Buts
- Nov 22 2008 12:55AM EST
- FDIC Not Insuring Fed Funds
- Nov 21 2008 10:30PM EST
- Counterparty Risk and Potential Losses from OTC Derivatives
- Nov 20 2008 4:27PM EST
- Dining Democracy
- Nov 19 2008 6:44AM EST
- Recession Dating
- Nov 17 2008 11:21AM EST
- The Best and Worst Restaurants in Manhattan
- Nov 17 2008 7:45AM EST
Categories
Links
- Email me

- Geary Behaviour Centre

- NBER Working Papers

- Social Science Statistics Blog

- Decision Science News

- Freakonomics

- New York Federal Reserve Research

- Statistical Modeling, Causal Inference, and Social Science

- Marginal Revolution

- EconTalk

- MoneyScience

- VoxEU

- Journal of Interest

- Bluematter

- Economist's View

- Research Recap

- Social Science Research Network

- Institute for the Study of Labor

- EconPapers

- Real Time Economics

- Center for Economic Policy Research

- B.I.S. Working Papers

- C.B.O. Director's Blog

- Federal Reserve Working Papers

- Institute for the Study of Labor

- O.E.C.D. Factblog

- Philadelphia Fed Research

- St. Louis Fed Research

- Sabernomics

- Sabermetric Research

- Economic Principals

- Numbers Guy

- Econbrowser

- STATS Blog

- Jeff Frankel

- Junk Charts

- Predictably/Irrational

- Tim Harford

- TierneyLab

- Curious Capitalist

- DataPoints: The Dismal Scientist Blog










