Consumer Reports has just withdrawn a report on infant car seat test results. Apparently, the testing wrecked most of the car seats. This, in turn, has been reported to cause many parents to start doubting the usefulness of infant car seats! So what happened?
The press release describes the aim of the study:
"The original study, published in the February issue of Consumer Reports, was aimed at discovering how infant seats performed in tests at speeds that match those used in the government’s New Car Assessment Program (NCAP). "
In particular, "Our tests were intended to simulate side crashes at the NCAP speed of 38 mph."
What apparently happened was that the actual test was performed at a much higher speed... Consumer Reports decided to withdraw the report and do some more testing.
Was the study design faulty? Probably not. Were the data faulty? Probably not. It looks more like a failed link between the study originators and executers. The moral is that even a solid study design and a reliable execution can lead to disastrous results if communication is broken.
Friday, January 19, 2007
Wednesday, January 17, 2007
I just stumbled upon a short article in the Economist's Voice called "Freak-Freakonomics". The author, Prof. Ariel Rubinstein, attacks Levitt's book Freakonomics by claiming that it really has nothing to do with economics. The article is very critical of the book and spares no arrows. It almost looks like the "war of economists who want to get published". Although there have been some "wars of statisticians" over the centuries (e.g., that between classic and Bayesian statisticians), here the war is not over the data or the modeling. It is over the importance of the questions asked. I bet that the outcome of the publication of this article will actually be an increase in the sales of Freakonomics...