Scholars and activists have hypothesized a connection between environmental change and out-migration. In this paper we test this hypothesis using data from Nepal. We operationalize environmental change in terms of declining land cover, rising times required to gather organic inputs, increasing population density, and perceived declines in agricultural productivity. In general, environmental cha...

Forest conversion for agriculture expansion is the most salient signature of human occupation of the earth's land surface. Although population growth and deforestation are significantly associated at the global and regional scales, evidence for population links to deforestation at micro-scales-where people are actually clearing0020forests-is scant. Much of the planet's forest elimination is pro...

For the majority of species, per capita growth rate correlates negatively with population density. Although the popular logistic equation for the growth of a single species incorporates this intraspecific competition, multi-trophic models often ignore self-limitation of the consumers. Instead, these models often assume that the predator-prey interactions are purely exploitative, employing simpl...

Economic impacts of invasive species worldwide are substantial. Management strategies have been incorporated in population models to assess the effectiveness of management for reducing density, with the implicit assumption that economic impact of the invasive species will also decline. The optimal management effort, however, is that which minimizes the sum of both the management and impact cost...

The productivity enhancing capability of cities is widely noted. Yet, while urban innovative capacity is often assumed to arise due to the close proximity of diverse elements within cities, little empirical research has attempted to associate population density with urban innovation. Thus, this research investigates how the density of a specific class of workers, the " creative class " , affect...

Taylor's spatial scaling law concerns the relation between the variance and the mean population counts within areas of a given size. For a range of area sizes, the log of the variance often is an approximately linear function of the mean with a slope between 1 and 2, depending on the range of areas considered. In this paper, we investigate this relationship theoretically for random quadrat samp...

This paper examines the central hypothesis of the influential Malthusian theory, according to which improvements in the technological environment during the pre-industrial era had generated only temporary gains in income per capita, eventually leading to a larger, but not significantly richer, population. Exploiting exogenous sources of cross-country variations in land productivity and the leve...

OBJECTIVE To investigate (1) the relative contributions of family and contextual characteristics to observed variation in disenrollment rates from the State Children's Health Insurance Program (SCHIP), and (2) whether context explains observed family-level patterns. DATA SOURCES We use secondary data on 24,628 families enrolled in New Jersey's SCHIP program (NJ KidCare), and county-level data...

Introduction About 60% of Nairobi residents live in slums with higher poverty, population density prevalence diseases and lower health access than the city average. Some residents own livestock or in are in contact with its products. Most slums dwellers work outside slums. Thus, health surveillance in slum area is vital because of potential disease outbreaks and spread. Yet, little is known on ...