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.

     

Understanding Cumulative Risk Perception from Judgments and Choices: An Application to Flood Risks

Catastrophic events, such as floods, earthquakes, hurricanes, and tsunamis, are rare, yet the cumulative risk of each event occurring at least once over an extended time period can be substantial. In this work, we assess the perception of cumulative flood risks, how those perceptions affect the choice of insurance, and whether perceptions and choices are influenced by cumulative risk information. We find that participants' cumulative risk judgments are well represented by a bimodal distribution, with a group that severely underestimates the risk and a group that moderately overestimates it. Individuals who underestimate cumulative risks make more risk‐seeking choices compared to those who overestimate cumulative risks. Providing explicit cumulative risk information for relevant time periods, as opposed to annual probabilities, is an inexpensive and effective way to improve both the perception of cumulative risk and the choices people make to protect against that risk.     

Comparing the Prevalence and Organizational Distinctiveness of Faith-Based and Secular Development NGOs in Canada

Faith-based development organizations (FBOs) have been argued to deliver more cost-efficient development projects than their secular counterparts through exclusive access to faith networks, which provide predictable decentralized funding, the recruitment of volunteers, low employee salaries, and less overhead and indirect costs. To date, however, comparative analyses of religious and secular organizations have relied on a case-by-case approach, limiting the generalizability of findings. This study addresses this methodological gap by analyzing Registered Charity Information Return filings and organizational websites of 844 Canadian development NGOs to determine the proportion of FBOs and their organizational distinctiveness. The results show that FBOs comprise 40% of the Canadian NGO sector in terms of the number of organizations and their expenditures in developing countries, and are significantly less reliant on federal funding (p?<?.1), pay employees lower salaries (p?<?.01), but do not exhibit a significant difference in their expenditures on overhead and indirect costs. Thus, Canadian FBOs participation in faith networks shapes their organizational modus operandi but does not result in a low overhead alternative to secular NGOs.

     

Volume 30

Theory and Society -     

Cognitive-behavioral-expressive interventions with aggressive and resistant youths.

Research into the nature of aggressive behavior in youths has demonstrated that these youths are often the victims of abuse, exhibit aggressive behavior in early childhood, and remain aggressive into young adulthood. The treatment approach described in this article is a modification of Monahan's [1981] model of the prediction of violent behavior and the anger-management approach of Novaco [1985], and integrates the developmental models of Piaget [1963] and Erikson [1959]. The program is a combination of cognitive, behavioral, and expressive therapies and is targeted to the reduction of dysfunctional cognitive, affective, behavioral, and problem-solving patterns of aggressive youths. As referrals of such aggressive clients are often involuntary, interventions with unwilling and resistant clients are also presented.     

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.