Minimum-Cost Distances in Spatial Analysis

An axiomatic approach to distance is developed which focuses on those behavioral concepts of distance related to movement in space. In particular, spatial movement by behaving units is postulated to involve a choice from among some set of abstract trips in space, and implicitly, to involve the minimization of some relevant notion of trip costs. In this context, the relevant behavioral notion of distance in space is taken to be the minimum-cost distance generated by this choice process. These trip-cost concepts extend the classical notions of paths, path lengths, and shortest paths in metric spaces. Hence many of the analytical results of the paper involve extensions of classical shortest-path distance properties to minimum-cost distances. In addition to these extensions, a characterization theorem is given which specifies the possible functional relationships between trip costs and their associated path lengths. These relationships include most functional forms which are commonly employed in the literature.     

ESR dating of the Neanderthal site, Kebara Cave, Israel

In 1985 a Neanderthal skeleton was found in the cave of Kebara in southern Mt. Carmel. Electron spin resonance (ESR) dates have been obtained on tooth enamel of gazelles found in layer X, just overlying the layer in which the skeleton was found. Assuming early uptake of uranium by the teeth, they yield an age of 60 ± 6 ka; assuming gradual, linear uptake of uranium yields an age of 64 ± 6 ka. Both age estimates are consistent with a previous estimate for the skeleton, based on TL dating of burnt flint, of 60 ± 4 ka.     

A synthesis of macro and micro approaches to explaining migration: evidence from inter-state migration in the United States

The interrelationships between macro and micro factors in the analysis of interstate migration in the United States are explored. A synthesis between these factors is attempted "by combining objectively calibrated characteristics of states with their subjectively measured counterparts....First, the relationships between the objective variables and their subjective counterparts are analyzed. Second, both sets of variables are used to explain residential preferences and migration. Third, a series of path models are constructed to indicate how the subjective variables act as intervening variables between their objective counterparts and migration."