On the Alias Method for Generating Random Variables from a Discrete Distribution

The alias method of Walker is a clever, new, fast method for generating random variables from an arbitrary, specified discrete distribution. A simple probabilistic proof is given, in terms of mixtures, that the method works for any discrete distribution with a finite number of outcomes. A more efficient version of the table-generating portion of the method is described. Finally, a brief discussion on efficiency of the method is given. We believe that the generality, speed, and simplicity of the method make it attractive for use in generating discrete random variables.     

Toward Probabilistic Prediction of Flash Flood Human Impacts

This article focuses on conceptual and methodological developments allowing the integration of physical and social dynamics leading to model forecasts of circumstance‐specific human losses during a flash flood. To reach this objective, a random forest classifier is applied to assess the likelihood of fatality occurrence for a given circumstance as a function of representative indicators. Here, vehicle‐related circumstance is chosen as the literature indicates that most fatalities from flash flooding fall in this category. A database of flash flood events, with and without human losses from 2001 to 2011 in the United States, is supplemented with other variables describing the storm event, the spatial distribution of the sensitive characteristics of the exposed population, and built environment at the county level. The catastrophic flash floods of May 2015 in the states of Texas and Oklahoma are used as a case study to map the dynamics of the estimated probabilistic human risk on a daily scale. The results indicate the importance of time‐ and space‐dependent human vulnerability and risk assessment for short‐fuse flood events. The need for more systematic human impact data collection is also highlighted to advance impact‐based predictive models for flash flood casualties using machine‐learning approaches in the future.     

Morality as a Verb: The Process of Moral Development Within the “Family Culture”

The purpose of this paper was to examine many different theories of moral development, view their similarities and differences, and expand upon the role of the family in teaching morality. There have been many stage theories developed in order to understand the process of moral development. In addition, many researchers have criticized the stage models for not adequately incorporating the role of culture in shaping a child's moral stance. We believe that the child's family (not necessarily an American Western view of the family) is crucial in directly and indirectly translating cultural values to children. We review some prominent stage theories to moral development as a point of departure for looking at the crucial role of the family culture. The family teaches morality to children by finding a balance between the forces of individuation and connection.     

Teen Childbearing and Educational Attainment: A Comparison of Methods

This research examines the impact of teenage childbearing on secondary school completion, while focusing on the problem of causal ambiguity in the relationships among self-determined behaviours. Techniques for dealing with the teenage childbearing problem are discussed, and results from these methods are compared. Data from the High School and Beyond Study on young women (n = 5257) who were enrolled as sophomores in sample schools in February 1980 and who had not given birth before November 1980 are used. Results indicate that teen childbearing reduces the probability of completing high school by 8% to 10%. Some evidence suggests that programs that target reduction of teen childbearing in improving young women's education and subsequent economic and labor force outcomes.     

Satisfaction with Social Contacts of Older Europeans

This paper analyses the determinants of an important component of well-being among individuals aged 50 years or older in eleven European countries: satisfaction with social contacts. We use data from the Survey of Health, Ageing and Retirement in Europe and anchoring vignettes to correct for potential differences in responses scales across countries and socio-demographic groups. On average, older Europeans report being satisfied with their social contacts, but there exist substantial differences across countries: respondents from Northern countries tend to be more satisfied than individuals from Central or Mediterranean countries. Our analysis shows that correcting for response scale differentials alters the country ranking for of satisfaction with social contacts, while it has much less effect on the estimates of what drives within country determinants.     

Satisfaction with Job and Income Among Older Individuals Across European Countries

Using data on individuals of age 50 and older from 11 European countries, we analyze two economic aspects of subjective well-being of older Europeans: satisfaction with household income, and job satisfaction. Both have been shown to contribute substantially to overall well-being (satisfaction with life or happiness). We use anchoring vignettes to correct for potential differences in response scales across countries. The results highlight a large variation in self-reported income satisfaction, which is partly explained by differences in response scales. When differences in response scales are eliminated, the cross-country differences are quite well in line with differences in an objective measure of purchasing power of household income. There are common features in the response scale differences in job satisfaction and income satisfaction. French respondents tend to be critical in both assessments, while Danish and Dutch respondents are always on the optimistic end of the spectrum. Moreover, correcting for response scale differences decreases the cross-country association between satisfaction with income and job satisfaction among workers.