Bequests as a heir "disciple device."

This paper develops a model ofinter vivos gifts and bequests in a setting of moral hazard and adverse selection. Altruistic parents do not perfectly know how much effort their children make to earn their living, nor do they know their true level of ability.Inter vivos gifts take place prior to the realization of the children's earnings whereas at the moment of bequests, parents do observe them. We show that an optimal transfer policy generally uses a mix ofinter vivos gifts — deemed as more efficient — and bequests — deemed as more redistributive.We are thankful to Allessandro Cigno, Jacques Cremer, Claude d Aspremont and anonymous referees for their comments.Responsible editor: Alessandro Cigno     

The health status of elderly people and the new direction of health services

The projected increase of people in Japan aged 75 years and older in the years to come implies the increase of the disabled elderly. Thus, the core of societal preparation for the aging of the population is generally considered to be the expansion of services for the disabled elderly. However, gerontological studies on the health status of the elderly conducted in Japan show that the prevalence of disability is quite low and even decreasing. Relative to the services for the disabled elderly, preventive services for the healthy elderly have long been overlooked. In 1994, the Metropolitan Tokyo Government organized a task force to develop a new health education program as the preventive health service for the healthy urban elderly. A preliminary plan outlining the health education program--consisting of propagation with a booklet, on-the-job training of practitioners, and development of new curricula and teaching materials--was proposed by the authors for discussion within the task force. Although the inquiry has just begun and the plan is still nascent, it seems adequate to fit the needs for preventive health services in the near future.     

Understanding the bear movement in gay male culture: redefining masculinity

The bear movement emerged in the gay male culture of the 1980s, but little research on this group has been conducted. The purpose of this qualitative study was to examine the meanings and functions of bear identity. Six bear-identified men participated in intensive interviews investigating this question. Results suggest that men who identify as bears consciously adopt a masculine aesthetic that signifies values of self-acceptance and maturity. The participants described the acceptance of diverse body shapes and ages within the bear community as leading to positive self-esteem and body image. Results are discussed in relation to clinical and advocacy work. They broaden the awareness of the diversity of cultures that exist within the gay community.     

The impact of children on a parent's risk of suicide following death of a spouse, Belgium 1991-96

Since Durkheim's work on suicide, the family has widely been seen as providing partial protection against the development of tendencies to suicide. This study assesses the impact of parenthood (both number of children and age of youngest child) on suicide following the death of a spouse. Using data for Belgium in the 5 years following the 1991 census, the study adopts a nested case-control design with information on 3,800 suicides and 75,673 matched controls. The analysis takes into account several social-economic variables. The findings show that the impact of children on the elevated suicide levels found among widows and widowers relative to the still married can be positive or negative, and differs by both age and sex of the parent, age of the child or children, and time since bereavement.     

A new estimate of permanent sterility by age: sterility defined as the inability to conceive

The proportion of couples permanently sterile beyond a certain age is an important component of the reproductive process. Unless medical assistance is used, this age is the upper bound of the fecund period. Most estimates of sterility by age of the woman have been derived from natural fertility populations, in which the number of births and the timing of the last birth (of the complete reproductive history) were not controlled by the couples. Because data on these populations do not include pregnancies not ending in a live birth, the sterility estimates apply to the proportion of couples unable to conceive and to have a live birth. For this reason, it is useful to have an estimate of sterility based on the risk of conceiving, independently of the fate of the pregnancy. Using this new estimate, sterility increases with age much more slowly than with most previous estimates.     

Moving and union dissolution

This paper examines the effect of migration and residential mobility on union dissolution among married and cohabiting couples. Moving is a stressful life event, and a large, multidisciplinary literature has shown that family migration often benefits one partner (usually the man) more than the other Even so, no study to date has examined the possible impact of within-nation geographical mobility on union dissolution. We base our longitudinal analysis on retrospective event-history data from Austria. Our results show that couples who move frequently have a significantly higher risk of union dissolution, and we suggest a variety of mechanisms that may explain this.     

IMPROVING POPULATION-SPECIFIC ALLELE FREQUENCY ESTIMATES BY ADAPTING SUPPLEMENTAL DATA: AN EMPIRICAL BAYES APPROACH

Estimation of the allele frequency at genetic markers is a key ingredient in biological and biomedical research, such as studies of human genetic variation or of the genetic etiology of heritable traits. As genetic data becomes increasingly available, investigators face a dilemma: when should data from other studies and population subgroups be pooled with the primary data? Pooling additional samples will generally reduce the variance of the frequency estimates; however, used inappropriately, pooled estimates can be severely biased due to population stratification. Because of this potential bias, most investigators avoid pooling, even for samples with the same ethnic background and residing on the same continent. Here, we propose an empirical Bayes approach for estimating allele frequencies of single nucleotide polymorphisms. This procedure adaptively incorporates genotypes from related samples, so that more similar samples have a greater influence on the estimates. In every example we have considered, our estimator achieves a mean squared error (MSE) that is smaller than either pooling or not, and sometimes substantially improves over both extremes. The bias introduced is small, as is shown by a simulation study that is carefully matched to a real data example. Our method is particularly useful when small groups of individuals are genotyped at a large number of markers, a situation we are likely to encounter in a genome-wide association study.     

Models for the analysis of C-reactive protein in statin trials

Elevation in C-reactive protein (CRP) is an independent risk factor for cardiovascular disease progression and levels are reduced by treatment with statins. However, on-treatment CRP, given baseline CRP and treatment, is not normally distributed and outliers exist even when transformations are applied. Although classical non-parametric tests address some of these issues, they do not enable straightforward inclusion of covariate information. The aims of this study were to produce a model that improved efficiency and accuracy of analysis of CRP data. Estimation of treatment effects and identification of outliers were addressed using controlled trials of rosuvastatin. The robust statistical technique of MM-estimation was used to fit models to data in the presence of outliers and was compared with least-squares estimation. To develop the model, appropriate transformations of the response and baseline variables were selected. The model was used to investigate how on-treatment CRP related to baseline CRP and estimated treatment effects with rosuvastatin. On comparing least-squares and MM-estimation, MM-estimation was superior to least-squares estimation in that parameter estimates were more efficient and outliers were clearly identified. Relative reductions in CRP were higher at higher baseline CRP levels. There was also evidence of a dose-response relationship between CRP reductions from baseline and rosuvastatin. Several large outliers were identified, although there did not appear to be any relationships between the incidence of outliers and treatments. In conclusion, using robust estimation to model CRP data is superior to least-squares estimation and non-parametric tests in terms of efficiency, outlier identification and the ability to include covariate information.