Model averaging for treatment effect estimation in subgroups

In many clinical trials, biological, pharmacological, or clinical information is used to define candidate subgroups of patients that might have a differential treatment effect. Once the trial results are available, interest will focus on subgroups with an increased treatment effect. Estimating a treatment effect for these groups, together with an adequate uncertainty statement is challenging, owing to the resulting “random high” / selection bias. In this paper, we will investigate Bayesian model averaging to address this problem. The general motivation for the use of model averaging is to realize that subgroup selection can be viewed as model selection, so that methods to deal with model selection uncertainty, such as model averaging, can be used also in this setting. Simulations are used to evaluate the performance of the proposed approach. We illustrate it on an example early‐phase clinical trial.     

Stagnation only on the surface? The implications of skill and family responsibilities for the gender wage gap in Sweden, 1974–2010

The wage differential between women and men persists in advanced economies despite the inflow of women into qualified occupations in recent years. Using five waves of the Swedish Level‐of‐Living Survey (LNU), this paper explores the gender wage gap in Sweden during the 1974–2010 period overall and by skill level. The empirical analyses showed that the general gender wage gap has been nearly unchanged for the past 30 years. However, the gender difference in wage in less qualified occupations fell considerably, whereas the gender pay gap remained stable for men and women in qualified occupations. The larger significance of family responsibilities for wages in qualified occupations is one likely explanation for this result.     

The Courtship Dance: Patterns of Nonverbal Synchronization in Opposite-Sex Encounters

This study examines the existence of behavioral correlates of synchronization on different levels of analysis and methods. We were unable to demonstrate a relation between synchronization defined in terms of movement echo or position mirroring and subjective experience of pleasure and interest in opposite-sex encounters. Significant results were found for a phenomenon we describe as hierarchically patterned synchronization. These patterns were identified with the help of a newly developed search algorithm. If a female is interested in a male, highly complex patterns of behavior with a constant time structure emerge. The patterns are pair-specific and independent from behavioral content. This rhythmic structure of interactions is discussed in functional terms of human courtship.     

Bird diversity in a subtropical South-American City: effects of noise levels,arborisation and human population density

Cities are highly modified environments in which the only areas that resemble natural landscapes are urban parks with low human population density. Attempts are frequently made to maintain high bird diversity in cities for aesthetic or educational reasons. However, it remains unclear whether local site characteristics are important in determining bird assemblage composition or whether simplification of the assemblage is an inevitable consequence of the changes associated with human population density. From May 1998 to December 1999, we undertook bird counts at 521 points in Porto Alegre, Rio Grande do Sul, southern Brazil. Our main goal was to understand the pattern of distribution of the bird species richness and density within the city and determine which variables most affect species assemblages. We recorded 132 species belonging to 43 families that are common in Rio Grande do Sul and obtained quantitative data on 121 species in survey sites. The two most abundant species (House Sparrow, Passer domesticus and Rock dove, Columba livia) were exotics. Analysis based on a reduced subset of 134 points surveyed in spring/early summer suggested that there was a North–south gradient in assemblage structure. Variation in assemblage structure was also affected by the number of trees, urban noise and human population density. However, human population density had a much smaller effect on richness and assemblage structure than variables subject to management, such as tree density and noise levels. These results suggest that complex communities may be maintained in densely populated urban areas of sub-tropical South-America given adequate urban planning.     

Canada's Most Wanted: Pioneer Women on the Western Prairies*

Cet article analyse les expériences des femmes pendant la colonisation des Prairies au Canada en mettant l'accent sur leur travail, sur leurs aptitudes et sur les capacites d'adaptation a l'environnement naturel et aux obstacles économiques auxquels ces femmes et leurs families se sont mesurés. Bien que les attitudes patriarcales domi‐nantes, la législation et les principes économiques aient quelque peu occulté les contributions des femmes, les efforts qu'elles ont déployés en Saskatchewan illustrent la «souplesse» dont ont fait preuve les fermières dans l'accomplissement de tâches productives et non productives. L'article démontre que cette souplesse a constitué un facteur déterminant de la survie des fermes familiales et, par là, du succès de l'industrie du blé. This article analyzes women's experiences during the settlement of the western prairie region of Canada. Attention is placed on their labour, skills and ability to adapt to the natural environment and the economic obstacles that they and their families encountered. While prevailing patriarchal attitudes, legislation and economic principles obscured women's contributions, the efforts of women in Saskatchewan are used to highlight the “flexibility” exhibited by farm women in performing productive and non‐productive labour. It is argued that this flexibility was critical to the survival of family farms, and thus to the success of the wheat economy.     

From childhood to young adulthood: the importance of self-esteem during childhood for occupational achievements among young men and women

This study investigates the impact of self-esteem during childhood on men’s and women’s occupational prestige in young adulthood. By combining first-hand information from parents in the Swedish Level-of-Living surveys (LNU) 2000 and their children in the Child-LNU in 2000 and the follow-up study in LNU-2010, we are able to assess how self-esteem during adolescence is related to occupational prestige in adulthood. Multivariate analyses were used to determine whether associations between self-esteem (global and domain-specific) in childhood (aged 10–18 years) and occupational prestige in young adulthood (aged 20–28) exist and, if so, what the magnitudes of these associations are for each respective gender.

For women, there is a positive association between confidence in mathematics and prestige, even when accounting for actual math grades. Global self-esteem is positively related to later occupational prestige as well. For men, self-esteem is unrelated to occupational prestige. Only actual performance in mathematics is important for men’s occupational achievements.

These results indicate the importance of taking gender differences into account when investigating how self-esteem is related to outcomes in young adulthood. A possible implication is the importance of focusing on the development of self-esteem among children, particularly girls, in school.     

A new age of old age?: Gerotranscendence and the re-enchantment of aging

Gerotranscendence theory is reviewed regarding its content, development, diffusion, impact, empirical results, and ontology. Gerotranscendence theory describes a “natural” alteration of consciousness in old age leading to “wisdom” and a qualitative break with a mid-life rational and materialist world-view. According to the theory, gerotranscendence is obstructed by a lack of alternative values and roles in old age in Western societies. Theoretically and in clinical practice, gerotranscendence theory has been linked to psychoanalysis. It is concluded that gerotranscendence theory is empirically weak, has parallels in the New Age movement as well as in romantic Orientalism, and can be understood as an attempt to re-enchant aging.     

Is Eradication of the Pinewood Nematode (Bursaphelenchus xylophilus) Likely? An Evaluation of Current Contingency Plans

The pinewood nematode (PWN) is one of the worst tree‐killing exotic pests in East‐Asian countries. The first European record of establishment in Portugal in 1999 triggered extensive surveys and contingency plans for eradication in European countries, including immediate removal of large areas of conifer host trees. Using Norway as an example, we applied a simulation model to evaluate the chance of successful eradication of a hypothetical introduction by the current contingency plan in a northern area where wilting symptoms are not expected to occur. Despite a highly variable spread of nematode infestations in space and time, the probability of successful eradication in 20 years was consistently low (mean 0.035, SE 0.02). The low success did not change significantly by varying the biological parameters in sensitivity analyses (SA), probably due to the late detection of infestations by the survey (mean 14.3 years). SA revealed a strong influence of management parameters. However, a high probability of eradication required unrealistic measures: achieving an eradication probability of 0.99 in 20 years required 10,000 survey samples per year and a host tree removal radius of 8,000 m around each detection point.