Lies, Damn Lies, and National Review (Part II)

Some time ago, the New York Times reported on census data that shows that only a minority of American women are married and living with their husband. Thomas Sowell writes in National Review to complain about the way the Times misleads with statistics. He repeats points made earlier, in the same magazine, by Jennifer Morse. (Namely, that the claim depends on the definition of "woman" and of "living with.")

But this is part of a pattern, Mr. Sowell writes, because,

Innumerable sources have quoted a statistic that half of all marriages end in divorce — another conclusion based on creative manipulation of words, rather than on hard facts.

The statistic is partly based on the fact that, in recent years, there have been about half as many divorces as marriages in any given year. It is of course not quite correct to project that half of the marriages are going to end in divorce: if the number of people getting married increases with time then, all other things being equal, the ratio of divorces to marriages in a given year underestimates the true fraction of marriages ending in divorce. Conversely, if the number of marriages goes down with time, one has an overestimate. I would suppose, however, that demographers take such trends into account in their models.

Sowell's objection is, of course, considerably more creative:

The fact that there may be half as many divorces in a given year as there are marriages in that year does not mean that half of all marriages end in divorce.

It is completely misleading to compare all the divorces in one year — from marriages begun years and even decades earlier — with the number of marriages begun in that one year.