Local Subpopulations Research Articles

Improving Estimates of Local Populations through Public Use Samples

Abstract Obtaining good estimates of local populations and subpopulations is always a problem with urban planners. One method widely used for this purpose is to count dwelling units and then multiply by a household population multiplier. A great weakness of this approach—the appropriateness of the multiplier used—can be improved upon using a data source known as the census public use samples. These samples of household records from the 1970 U.S. census of population provide a basis for tailor-made household population multipliers. Multipliers can be selected to be appropriate to the region, type of city, the neighborhood, type and age of structure, and for other observable characteristics of the dwelling unit. Tests reported in this article indicate that the multipliers to be obtained from the public use samples compare extremely well with the best available elsewhere. Further, they are available at a cost which is a tiny fraction of that for customary survey sources of data.

On the neighbor effect and the evolution of altruistic traits

The long-term effects of natural selection are studied in a large population in which survival and fertility of any individual depend not only on its own genotype, but also on the genetic features of neighboring members of its species—a relatively small group of individuals sharing its social community or immediate geographic vicinity and partially separated from similar groups within the population as a whole. Random drift within such local groups or subpopulations, as well as migration among them are taken into account. Conditions for the evolution of altruistic biological traits, are analyzed. Special consideration is given to natural mechanisms of birth control, and possible implications to human evolution are offered. In agreement with Wright (1945), low demographic mobility proves to be the most crucial factor for the evolution of altruistic traits.