The danger of false positives

As I mentioned earlier, I’m teaching a first-year seminar this semester called “Science or Nonsense?” On Monday and Wednesday this week we discussed some math/stats/numeracy topics. We talked about the Sally Clark murder trial, the prosecutor’s fallacy, the use of DNA testing in law enforcement, Simpson’s paradox, the danger of false positives, and the 2009…

Irrational rotations of the circle and Benford’s law

Take a collection of real-world data such as the lengths of all rivers in the world, the populations of counties in the United States, the net worths of American corporations, or the street addresses of all residents of Detroit. Strip away all the information except the leading digits. What percentage of these digits do you…

A correlation: 19th century cotton production and Obama votes

The Strange Maps blog has the following interesting map mash-up. This is an overlay of two maps. One is the 2008 presidential election results and the other is cotton production in 1860 (each dot represents 2000 bales). Strange Maps writes: The link between these two maps is not causal, but correlational, and the correlation is…

How did the pollsters do?

A few weeks ago I wrote about Fivethirtyeight.com, the website run by Nate Silver which made political predictions based on aggregating existing polls. You may want to check out a blog post by Carl Bialik, The Numbers Guy at the Wall Street Journal, in which he looks the accuracy of Nate Silver’s and other pollsters’ predictions. Here’s…

Tao on political polls

Fields Medalist and mathematics blogger, Terrence Tao, has an interesting and timely post on political polls on his blog.

Aggregating political polls

A colleague and I were talking about how fun it would be to be teaching a statistics class during this presidential election season—especially talking about the political polling process. Recently I came across Fivethirtyeight.com, an interesting website that takes published political polls, applies its own analysis to them, and puts out its own predictions. (It is named after the number of electors in…