Spectroscopic method rapidly identifies proteins

In the last four decades, human fertility has declined across the globe, a trend that policy experts predict will continue. As a result, international migration will increasingly affect the demographic future of many nations. Joel Cohen et al. devised a generalized linear model to predict the yearly number of regional and international migrants. The model includes projected demographic variables and unchanging geographic ones, such as the population totals and population density of the origins and destinations of migrants, the distance between the regions, and estimates of differences in reporting methods or institutional characteristics. Based on data from 11 countries, the authors’ model was able to accurately estimate the annual numbers of migrants from 228 origins and to 195 destinations during 1960–2004. This approach may help improve existing demographic procedures for projecting international migration, the authors say. — F.A.