Spatial models of voting have dominated mathematical political theory since the seminal work of Downs. The Downsian model assumes that each elector votes on the basis of his utility function which depends only on the distance between his preferred policy platform and the ones proposed by candidates. A succession of papers introduces valence issues into the model, i.e. candidates’ characteristic...

The proportion of Americans who reported no religious preference doubled from 7 percent to 14 percent in the 1990s. This dramatic change may have resulted from demographic shifts, increasing religious skepticism, or the mix of politics and religion that characterized the 1990s. One demographic factor is the succession of generations; the percentage of adults who had been raised with no religion...

In an environment where managers’ability to generate pro…ts changes stochastically over time, we characterize the optimal turnover policy for a …rm hiring a succession of managers. The focus is on the interaction between the compensation scheme used to incentivize the managers’e¤ort and the retention policy used to screen the managers’types and induce the desired turnover. Our key positive resu...

The minimum postmortem interval can be estimated based on knowledge of the pattern of insect succession on a corpse. To use this approach requires that we take into account the rates of insect development associated with particular climatological conditions of the region. This study is the first to look at insect succession on decomposing carcasses in the high altitude plains (Paramo) in Colomb...

Rates of ecosystem recovery following disturbance affect many ecological processes, including carbon cycling in the biosphere. Here, we present a model that predicts the temperature dependence of the biomass accumulation rate following disturbances in forests. Model predictions are derived based on allometric and biochemical principles that govern plant energetics and are tested using a global ...

The vegetation composition of a post-fke succession in Aleppo pine forests of Anica, Greece, was studied by a synchronic method. The sites form a post-fire chronosequence and have typical Mediterranean climate. Data on the flora of the burned sites, growth and life forms of the various plant taxa, as weU as on vegetation smcture are provided. The burned ecosystems recovered quite rapidly. Durin...

This paper deals with the succession process of a food web model consisting of one herbivore, two autotrophs and available nutrient in the environment in a closed nutrient flux. The model provides a way of describing successional changes in the form of species replacement with increasing nutrient levels. It is shown that distinct threshold (with upper and lower) values of nutrient are required ...