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Americans Drove Less in 2005
antifoidulus writes "CNN is reporting on a study that shows that not only did Americans buy more fuel efficient vehicles in 2005 (although sadly this trend reversed itself in the later half of 2006) but they also drove slightly less on average, according to the article, 'The drop in driving was small — the average American drove 13,657 miles (21,978.8 km) per year in 2005, down from 13,711 miles in 2004.' This is the first drop since the energy crisis of the late 70's. However, although SUV and mini-van sales have been falling, they still represent over half of the private vehicle sales in the United States."
It is amazing that how news reporter are so illiterate when it comes to math and science. The figures they report indicates no conclusive reduction (change) in driving habits at all. When we measure a quantity there is always some error in that measurement. Driving habit is pretty much a random event when average over millions of people. Thus, a good approximation (I don't claim it to be the most accurate) of its associated error is 1/sqrt(x), and thus x +- x/sqrt(x) is a proper way for indicating the average x. In this specific case, it is 13600 +- ~110. Thus the change (~50) is smaller then a sigma away from the average. The proper way to report this would be: Americans don't care about the environment, and they have the money to burn the same amount of fossil fuel as they did last year.