math is hard

Just wanted to re-post my comment from a thread over at Les Jones. He quotes Mark Steyn there:

But, if I had to be a bit more mathematical about it, I’d look at it this way. If the Democrats ever want to take back the White House, 2008 is their best shot. After the 2010 census, the electoral college apportionment for the 2012 Presidential campaign will reflect the population shifts to the south and west – ie, growing Republican “red” states will get more votes and declining Democrat “blue” states will have fewer. The trouble with being a party that promotes abortion as a sacrament is that after a generation or two it catches up with you: in 2004, the 16 states with the lowest fertility rate voted for John Kerry; 25 of the 26 with the highest fertility rate voted for George W Bush. In the long run, a lot of Democratic turf is looking as demographically barren as the European Union.

His analysis isn’t very mathematical, or statistically relevant at all. As I commented there:

a) abortion has little impact on fertility rates in this country (and in most others)
b) correlation is not causation – most of the blue states are those with predominantly urban areas. This statistical skew is multicausal and well-documented (and oft-debated). Fertility rates also follow this pattern – they are always lower in urban areas than rural.
c) Fertility rate is only one determinant in population demographics.

In conclusion, his comment on abortion is terribly off, and further, I sure hope Mark isn’t seriously hinging his electoral hopes on population shifts.