The differential influence of geographic isolation on environmental migration: a study of internal migration amidst degrading conditions in the central Pacific

Population and Environment - This study investigates how geographic isolation interacts with declining environmental and economic conditions in Kiribati, an island nation wherein which limited...     

Instrumental variable estimation in ordinal probit models with mismeasured predictors

Researchers in the medical, health, and social sciences routinely encounter ordinal variables such as self‐reports of health or happiness. When modelling ordinal outcome variables, it is common to have covariates, for example, attitudes, family income, retrospective variables, measured with error. As is well known, ignoring even random error in covariates can bias coefficients and hence prejudice the estimates of effects. We propose an instrumental variable approach to the estimation of a probit model with an ordinal response and mismeasured predictor variables. We obtain likelihood‐based and method of moments estimators that are consistent and asymptotically normally distributed under general conditions. These estimators are easy to compute, perform well and are robust against the normality assumption for the measurement errors in our simulation studies. The proposed method is applied to both simulated and real data. The Canadian Journal of Statistics 47: 653–667; 2019 © 2019 Statistical Society of Canada     

Diversity and assemblage filtering in ground-dwelling spiders (Araneae) along an urbanisation gradient in Denmark

Urban Ecosystems - We studied the effects on spiders of a three-step rural-urban urbanisation gradient near a Danish town embedded in a historically forested landscape. Using pitfall traps set in...     

TRUST,COORDINATION, AND THE INDUSTRIAL ORGANIZATION OF POLITICAL ACTIVISM

We study political activism by several interest groups with private signals. When their ideological distance to the policymaker is small, a “low‐trust” regime prevails: agents frequently lobby even when it is unwarranted, taking advantage of the confirmation provided by others' activism; conversely, the policymaker responds only to generalized pressure. When ideological distance is large, a “high‐trust” regime prevails: lobbying behavior is disciplined by the potential contradiction from abstainers, and the policymaker's response threshold is correspondingly lower. Within some intermediate range, both equilibria coexist. We then study the optimal organization of influence activities, contrasting welfare levels when interest groups act independently and when they coordinate. (JEL: D72, D78, D82)     

Explaining Cross-Country Differences in Attitudes Towards Immigration in the EU-15

In this paper, we use data from the first two rounds of the European Social Survey to analyze the extent to which differences in average attitudes towards immigration across the EU-15 countries may be explained by differences in socioeconomic characteristics and individually perceived consequences of immigration, using an extension of a decomposition technique developed by Fairlie (2005). We find that despite the significant effects of socioeconomic characteristics on attitudes, differences in the distributions of these characteristics can only explain a modest share of the cross-country variation in average attitudes. A larger part can be explained by differences in perceived consequences of immigration, but the main part is still left unexplained. Apart from providing useful input for policy makers working in the area of immigration policy, this raises a number of questions for further research for which the ESS data can be successfully applied.

Depressive Symptoms Among Native and Immigrant Adolescents in Norway: The Role of Gender and Urbanization

The study investigates depressive symptoms among 3,431 adolescents aged 13–15 years. The sample comprises both native Norwegian and immigrant adolescents living in Norway. The main finding of the study is that the level of depressive symptoms is significantly higher among the immigrant adolescents than their Norwegian counterparts. When analysed separately for boys and girls, the difference is still significant for boys. Generally depressive symptoms are significantly higher among girls than among boys. Depressive symptoms, especially in boys, may also be related to the degree of urbanization of the area they live in. In cities, there is a significant difference between native Norwegian and immigrant boys, with immigrant boys having a higher level of depressive symptoms than native Norwegians. The implications for future research about immigrant adolescents and their psychosocial adjustment are discussed.

Combining Experts' Risk Judgments on Technology Performance of Phytoremediation: Self-Confidence Ratings, Averaging Procedures, and Formative Consensus Building

Expert panels and averaging procedures are common means for coping with the uncertainty of effects of technology application in complex environments. We investigate the connection between confidence and the validity of expert judgment. Moreover, a formative consensus building procedure (FCB) is introduced that generates probability statements on the performance of technologies, and we compare different algorithms for the statistical aggregation of individual judgments. The case study refers to an expert panel of 10 environmental scientists assessing the performance of a soil cleanup technology that uses the capability of certain plants to accumulate heavy metals from the soil in the plant body (phytoremediation). The panel members first provided individual statements on the effectiveness of a phytoremediation. Such statements can support policymakers, answering the questions concerning the expected performance of the new technology in contaminated areas. The present study reviews (1) the steps of the FCB, (2) the constraints of technology application (contaminants, soil structure, etc.), (3) the measurement of expert knowledge, (4) the statistical averaging and the discursive agreement procedures, and (5) the boundaries of application for the FCB method. The quantitative statement oriented part of FCB generates terms such as: "The probability that the concentration of soil contamination will be reduced by at least 50% is 0.8." The data suggest that taking the median of the individual expert estimates provides the most accurate aggregated estimate. The discursive agreement procedure of FCB appears suitable for deriving politically relevant singular statements rather than for obtaining comprehensive information about uncertainties as represented by probability distributions.