Multiple event times in the presence of informative censoring: modeling and analysis by copulas

Motivated by a breast cancer research program, this paper is concerned with the joint survivor function of multiple event times when their observations are subject to informative censoring caused by a terminating event. We formulate the correlation of the multiple event times together with the time to the terminating event by an Archimedean copula to account for the informative censoring. Adapting the widely used two-stage procedure under a copula model, we propose an easy-to-implement pseudo-likelihood based procedure for estimating the model parameters. The approach yields a new estimator for the marginal distribution of a single event time with semicompeting-risks data. We conduct both asymptotics and simulation studies to examine the proposed approach in consistency, efficiency, and robustness. Data from the breast cancer program are employed to illustrate this research.

     

The Social Construction of Asperger Syndrome: The pathologising of difference?

This article poses the question 'Is Asperger Syndrome (AS) a disorder or a neurological difference that has been socially constructed as a disorder?' AS is currently defined within the medical paradigm as a developmental disorder. Alternative conceptualisations of Asperger Syndrome have largely been absent within the academic discourse on AS. Drawing on the emerging field of disability studies we examine how the diagnostic category of AS has been socially constructed. Our contention is that Asperger Syndrome has been readily adopted as a category because of its value as a category of special education. In other words, the school is a pivotal institution in the dissemination of AS as a category. Within the framework of special needs AS is viewed as a social disability and the aim of professional interventions is to help to rehabilitate or 'normalise' the child. In attempting to re-frame this conceptualisation of AS it is important to shift the emphasis from issues of diagnosis and evaluation to examining the social implications of representing children as having AS.     

Zimbabwe's AIDS action programme for schools

AIDS education started very early in Zimbabwe and is now compulsory in all schools. This evaluation documents the development of the primary and secondary school AIDS Action Programme from 1991 to 1998. Six programme aspects were evaluated: programme start-up, planning and management, development of syllabi and materials, teacher training, research, monitoring and evaluation, and co-ordination. The Programme drew on resources from within the existing educational system. Due to broad-based consultation and participation, it was supported by Government and partners. Flexible management ensured implementation of mid-course corrections. It was concluded that school AIDS programmes should stress participatory teaching and learning methods and life-skills training. Curriculum writers and teachers needed training and supervision in participatory techniques. Cluster workshops between district and school levels were needed to strengthen the cascade model of teacher training that had been adopted. Systematic research, monitoring and evaluation were essential, including follow-ups to baseline surveys. The Zimbabwean programme was well-designed, relatively inexpensive and replicable.     

Factors Associated with Having Flextime: A Focus on Married Workers

To examine flexible work scheduling of married workers a conceptual framework was developed and tested using the 1997 Current Population Survey Work Schedules Supplement. Odds of flextime use were higher for married males, non-Hispanic whites, those with relatively higher levels of education and income, those with a preschool aged child, residents of the Midwest or West (as compared with the South), managers or professionals, and employees of the federal government.     

The transition to parenthood in Puerto Rico: Occupational status and the timing of first births

This study examines the relationship between occupational status and fertility timing during a period of rapid development in Puerto Rico. Our fundamental hypothesis is that women with higher status occupations face greater opportunity costs than those with less valued jobs and therefore will be more likely to postpone parenthood until later ages than women without such high costs. We test this hypothesis using event history techniques with data from the 1982 Puerto Rico Fertility and Family Planning Assessment, an island-wide survey of women between the ages of 15 and 49. The analysis examines the effects of occupational status on the timing of first births, and finds strong support for the basic hypothesis, especially regarding the post-ponement of teen births. After the teen years, the effects are less pronounced. Overall, it appears that employment opportunities have played an important role in childbearing decisions in Puerto Rico.An earlier version of this paper was presented at the annual meeting of the Population Association of America, Denver, Colorado, 30 April–2 May 1992.     

Achieving the indeterminate: Accomplishing degrees of certainty in life and death situations

This paper explores technology's pivotal position at the intersection of control and uncertainty. It examines two areas: Intensive Care and a Labour Ward. Building on the work of Davis (1960), it argues that certainty and uncertainty are socially constructable and reconstructable. This is actively achieved by the deployment of strategies involving particular paradigms (the biomedical model) and artefacts (medical technology). Power lies in control over knowledge and the structures and practices which sustain it, including those embedded in advanced technology. The contribution of medical technology to the achievement of certainty in Intensive Care and end-game Obstetrics (the Labour Ward) is considered. Achieved certainty in medical situations is seen as: the structured masking of uncertainty by the application of medical iconography, artefacts and techniques to create the illusion of certainty. The accomplishment of uncertainty in Obstetrics (as a precursor to technological intervention) is also explored. The accomplishment of uncertainty in medical situations is seen as associated with the structured projection of uncertainty, involving using medical discourse rooted in the medical paradigm to exaggerate the generality of risk and the probability of pathology. It is argued that the highly structured and routinised settings of ICU and the labour Ward, not only aid control by the medical profession but diminish perceptions of uncertainty.     

Sex differences in nonverbal expressiveness: Emotional expression,personality, and impressions

Sex differences in expressiveness are well documented, but the reasons for and correlates of these important differences are not well studied. A comprehensive set of emotion-relevant personality measures was administered to 40 female and 39 male undergraduate participants, who were also videotaped in three situations: engaging in natural social interaction, describing a past emotional experience, and posing various emotions. Videotapes were judged by sets of naive observers as to emotion communicated and overall impression. Expressive females, who appeared friendly and dominant in social interaction, were found to have a hostile/aggressive personality (but this was not true of males). Expressive females also tended to look angry/disgusted when describing happy and sad experiences. The findings suggest that nonverbally skilled, charismatic women (but not men) may often possess a dominant/aggressive but self-controlled personality, in a new twist on the theory that sex differences in expressiveness result in part from the oppression of women in society.This research was supported in part by an intramural research grant from University of California, Riverside.