Postprint version. Published in International Encyclopedia of the Social and Behavioral Sciences, January 1, 2002, pages 13425-13429.
NOTE: At the time of publication, the author Hemalata C. Dandekar was not yet affiliated with Cal Poly.
The definitive version is available at http://dx.doi.org/10.1016/B0-08-043076-7/04422-3.
Urban, Community and Regional Planning