Ancestral Inference in Population Genetics Models with Selection (with Discussion)

A new algorithm is presented for exact simulation from the conditional distribution of the genealogical history of a sample, given the composition of the sample, for population genetics models with general diploid selection. The method applies to the usual diffusion approximation of evolution at a single locus, in a randomly mating population of constant size, for mutation models in which the distribution of the type of a mutant does not depend on the type of the progenitor allele; this includes any model with only two alleles. The new method is applied to ancestral inference for the two‐allele case, both with genic selection and heterozygote advantage and disadvantage, where one of the alleles is assumed to have resulted from a unique mutation event. The paper describes how the method could be used for inference when data are also available at neutral markers linked to the locus under selection. It also informally describes and constructs the non‐neutral Fleming–Viot measure‐valued diffusion.     

Attitude Differences Between Paid Workers and Volunteers

This study addresses the extension of research on paid employees to volunteer workers. Pearce (1978, 1993b) has postulated that job attitudes are substantially different between volunteers and paid employees, based on her work studying fourteen organizations employing either entirely volunteer workgroups or entirely paid workgroups. Another interpretation of her data would be that the organizational culture of such workgroups is different, not the individual job attitudes.     

A crash course in implementation theory

This paper is meant to familiarize the audience with some of the fundamental results in the theory of implementation and provide a quick progression to some open questions in the literature. Received: 26 March 2001/Accepted: 21 May 2001     

Moderators of the Relationship Between Physical Activity and Alcohol Consumption in College Students

Abstract

Objective: Among college students, several studies have found a positive relationship between physical activity and alcohol use. The current study tested gender, Greek status, and ethnicity as potential moderators of the physical activity-alcohol use relationship. Participants: Participants were college freshmen (n = 310) endorsing alcohol/drug use. Methods: Students completed questionnaires assessing a number of health behaviors. Results: Results indicated that gender and Greek status were significant moderators of the relationship between physical activity and alcohol consumption. There was a positive relationship between physical activity and alcohol use for men and Greeks, but not for females and non-Greeks. Conclusions: These findings suggest that exercise does not serve as a protective factor for any of the subgroups of college students studied and is positively associated with drinking among college students who are men and/or involved with the Greek system.     

THE FEMA TRAILER PARKS: NEGATIVE PERCEPTIONS AND THE SOCIAL STRUCTURE OF AVOIDANCE

In recent years, negative media attention has fostered the impression that Federal Emergency Management Agency (FEMA) parks are social wastelands filled with criminal elements and other undesirables. FEMA parks have subsequently come to be viewed by some as a major threat to the safety and quality of life of the local communities in which they are situated. This analysis addresses attitudes toward FEMA trailer parks in Baton Rouge after Hurricane Katrina among Baton Rouge residents. Drawing on the Locally Undesirable Land Use/Not in My Backyard (LULU/NIMBY) literature, the contact hypothesis, and a broad paradigm of social status and social control, we hypothesize that spatial proximity, contact, and social status will influence negative perceptions of the parks, while these same factors along with the negative perceptions will influence avoidance behaviors. The results indicate that living near a FEMA park is associated with less negative perceptions, while actually seeing trailer park residents is associated with more negative perceptions and a greater odds of avoidance, particularly changing driving routes. Whites are particularly concerned about crime associated with the parks, but interracial trust reduces negative perceptions of the parks and the likelihood of avoidance. Those who are likely to end up in a FEMA park if they were in the same situation are more friendly toward the parks and less likely to use avoidance techniques, and negative perceptions themselves are strong predictors of avoidance behaviors. We conclude with a discussion of directions for future research.     

Righteousness on two wheels: Bikers as a secular sect

The study concerns itself with a comparison of the value system of bikers, those who pursue a life‐style centered around motorcycles, with that of a religious sect Several parallels are drawn with the religious sect, in the function of the life‐style of bikers as well as the degree of commitment. The study is the product of several years of participant observation by the author.     

Madam Senator: Growth in Women's State Senate Representation, 1978–2010

Using a dataset of women state senators from all 50 states (1978–2010) and latent growth curve analysis, this article tests two longitudinal theories of the growth of women's political representation over time. Gender salience theory posits that women increase their political representation when they explicitly campaign on their gender. Political climate theory argues that women fare better electorally during periods when domestic issues predominate as opposed to international issues. Results provide support for gender salience theory, but the evidence is too mixed for political climate theory to provide a plausible explanation for the growth in women's state-level political representation. By political party, results suggest that Democratic women were generally advantaged over Republican women; however, Republican women exclusively benefited in the 1992 and 2010 elections. This article concludes with an assessment of the two longitudinal theories and what they may tell us more broadly about women in politics.     

THE NEGATIVE CONSEQUENCES OF HEAVY DRINKING AND ASSOCIATED DISRUPTIVE BEHAVIORS FOR SIBLING RELATIONSHIP PERFORMANCE

This study is designed to extend the sociological research on alcohol use and family relationships. We focus specifically on how heavy drinking by a sibling erodes the sibling relationship performance. Using survey data gathered from 339 college students attending a large Southern University, the results indicate that siblings who are heavy drinkers exhibit substantially poorer sibling relationship performance than nondrinking siblings. However, the data also indicate that there is an important factor mediating this link. Once a measure of disruptive behaviors often associated with heavy drinking is controlled, sibling drinking is no longer a significant predictor of sibling relationship performance. Hence, the inverse relationship between sibling drinking and sibling relationship performance is actually accounted for by an underlying association between disruptive behaviors associated with heavy drinking and poor sibling relationship performance. We conclude with a discussion of the limitations of the study and the theoretical implications of the findings, including suggestions for future research in this area.