You’d think knowing mathematics would help me understand things, but there’s an article in this week’s Economist for which it was just the reverse.

It seems that women tend to give birth in the wee hours of the morning, for reasons of natural selection. The article describes two groups of women studied and then says that “the average time of birth” was 6.34am for one group and 4.18am for the other.

The average time of birth??!!  To a mathematician this is patently a meaningless notion. How can you talk about the average time of something when the time variable is periodic?

After some thought, you realize that they must be measuring time by a 24-hour clock starting at midnight, and then, well, maybe it’s arbitrary, but at least the average is well defined. After a little more thought you realize that to anyone without mathematical training, this would be perfectly obvious.

[27 April 2017]