Friday, April 30, 2004

More Great Dispersal

Americans (and others) have been getting older, richer and more technologically enhanced -- all of these more rapidly than ever -- for some years now. Social scientists have more and better data, more powerful hardware, fancier software, and occasionally, better theory. But can we keep up? Natural scientists also have better tools but their subject matter (with notable biological exceptions) does not change. Certainly not as rapidly.

Much of what is interesting occurs in cities -- and is shaped by them as it, in turn, shapes them -- but even the "city" label is quaint. People are settling in ways and places that require new labels. The National Household Travel Survey copes with the Great Dispersal by placing all of us in either "urban", "second city", "suburban", "town: or "rural" places.

Comparing the 2001 NHTS with its predecessor (1995) NPTS, we see that trip times have been increasing, across the board (all places, all trip purposes). This is news because similar increases had not been apparent in comparisons over previous survey years. How have people coped? Predictably, they traveled less, across the board. Elasticities range from -0.7 to just less than -1.0. This is not a ceteris paribus comparison and we must be careful.

Is this a bad news or a good news story? A good news take suggests that cheaper communications help many of us avoid more expensive travel. But, are we better off? Social science is hard work.