Discovering Spatio-Temporal Models of the Spread of West Nile Virus

Emerging infectious diseases are characterized by complex interactions among disease agents, vectors, wildlife, humans, and the environment. Since the appearance of West Nile virus (WNV) in New York City in 1999, it has infected over 8,000 people in the United States, resulting in several hundred deaths in 46 contiguous states. The virus is transmitted by mosquitoes and maintained in various bird reservoir hosts. Its unexpected introduction, high morbidity, and rapid spread have left public health agencies facing severe time constraints in a theory-poor environment, dependent largely on observational data collected by independent survey efforts and much uncertainty. Current knowledge may be expressed as a priori constraints on models learned from data. Accordingly, we applied a Bayesian probabilistic relational approach to generate spatially and temporally linked models from heterogeneous data sources. Using data collected from multiple independent sources in Maryland, we discovered the integrated context in which infected birds are plausible indicators for positive mosquito pools and human cases for 2001 and 2002.     

Risk Assessment for Invasive Species

Although estimates vary, there is a broad agreement that invasive species impose major costs on the U.S. economy, as well as posing risks to nonmarket environmental goods and services and to public health. The domestic effort to manage risks associated with invasive species is coordinated by the National Invasive Species Council (NISC), which is charged with developing a science-based process to evaluate risks associated with the introduction and spread of invasive species. Various international agreements have also elevated invasive species issues onto the international policy agenda. The World Trade Organization (WTO) Sanitary and Phytosanitary (SPS) Agreement establishes rights and obligations to adhere to the discipline of scientific risk assessment to ensure that SPS measures are applied only to the extent required to protect human, animal, and plant health, and do not constitute arbitrary or unjustifiable technical barriers to trade. Currently, however, the field of risk assessment for invasive species is in its infancy. Therefore, there is a pressing need to formulate scientifically sound methods and approaches in this emerging field, while acknowledging that the demand for situation-specific empirical evidence is likely to persistently outstrip supply. To begin addressing this need, the Society for Risk Analysis Ecological Risk Assessment Specialty Group and the Ecological Society of America Theoretical Ecology Section convened a joint workshop to provide independent scientific input into the formulation of methods and processes for risk assessment of invasive species to ensure that the analytic processes used domestically and internationally will be firmly rooted in sound scientific principles.     

What unions do: Insights from economic theory

Conclusion I have attempted to distill a quite sizable body of literature written by modern economists on the theory of labor unions, with particular emphasis given to the “two faces” view of unions developed by Freeman and Medolf in What Do Unions Do? Many important ideas and contributions have necessarily been omitted, but hopefully the main contours and implications are captured.     

Incarceration and the Formation and Stability of Marital Unions

Rising imprisonment rates and declining marriage rates among low‐education African Americans motivate an analysis of the effects of incarceration on marriage. An event history analysis of 2,041 unmarried men from the National Longitudinal Survey of Youth suggests that men are unlikely to marry in the years they serve in prison. A separate analysis of 2,762 married men shows that incarceration during marriage significantly increases the risk of divorce or separation. We simulate aggregate marriage rates using estimates from the National Longitudinal Survey of Youth and find that the prevalence of marriage would change little if incarceration rates were reduced.     

Poverty Catchments: Migration,Residential Mobility,and Population Turnover in Impoverished Rural Illinois Communities

Abstract Research has thoroughly documented how out‐migration of the educated and skilled from rural areas leaves behind a poorer population and creates pockets of rural poverty. Recently, studies have recognized that the poor are also geographically mobile and that poverty migration patterns can reinforce rural poverty concentrations. In this process, certain impoverished rural communities in economically depressed regions receive a disproportionate share of poverty migrants, concentrating poverty in certain locations. This paper examines the conditions and processes through which poor rural communities become likely destinations for a highly mobile segment of the rural poor and near‐poor. Utilizing case studies of depressed rural Illinois communities, it investigates how the interplay of community factors and the behavior of migrants transforms rural communities from residentially stable to highly mobile, impoverished places.