[WilliamofCarmichael]

I got another one I remember from college psychology 101..

1. the incidences of rape increase during summer months
2. ice cream consumption increases during summer months

therefore the increase demand for ice cream is caused by the rapes? The rapist might be tired and hungry a student speculated.

Oh.. just in case. I wasn't that student. It took me a long time but I didn't say anything until I figured out days later that there was no correlation.. it was the weather.

[Erasmus]

I remember an instructive incident in my high school debate class.

As an exercise, our teacher introduced the fact that the crime rate per capita was higher for immigrants than for the non-immigant population. (I should add that this was over 50 years ago.) We were asked to analyze this as an assertion in a debate and come up with reasons why it might be true or on the other hand false or misleading.

One girl said it was plausible because foreigners, well you know about foreigners!

Our teacher pointed out that the average immigrant is adult, which skews the demographics with regard to crime; the non-immigrant population is skewed the other way because of the numbers of young children in that demographic.

In other words, the statistic was useless as given.