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.

     

Behavioral responses of rural and urban greater white-toothed shrews (Crocidura russula) to sound disturbance

Urban Ecosystems - The development of urban areas imposes challenges that wildlife must adapt to in order to persist in these new habitats. One of the greatest changes brought by urbanization has...     

What is educational entrepreneurship? Strategic action,temporality, and the expansion of US higher education

Theory and Society - The massive expansion of US higher education after World War II is a sociological puzzle: a spectacular feat of state capacity-building in a highly federated polity. Prior...     

Philippine NGOs and Multistakeholder Partnerships: Three Case Studies

This paper discusses an emerging role for Philippine NGOs—building and maintaining intersectoral cooperation among various sectors of society to tackle key issues like agricultural development, HIV/AIDS, and agrarian reform. The three case studies elaborated in the paper show that Philippine NGOs play important intermediary and bridging functions crucial for the success of multistakeholder partnerships. NGOs are well equipped for this because of their middle-class and professional nature and because of various characteristics like autonomy, flexibility, and the ability to mobilize resources.     

A class of symmetric bivariate uniform distributions

A class of symmetric bivariate uniform distributions is proposed for use in statistical modeling. The distributions may be constructed to be absolutely continuous with correlations as close to±1 as desired. Expressions for the correlations, regressions and copulas are found. An extension to three dimensions is proposed.     

Career Self‐Efficacy and Perceptions of Parent Support in Adolescent Career Development

The authors examined the relative contributions of both proximal and distal supports to the career interests and vocational self‐efficacy in a multiethnic sample (N = 139) of middle school adolescents. Consistent with Social Cognitive Career Theory, it was found that (a) vocational self‐efficacy and career planning/exploration efficacy consistently predicted young adolescents' career interests across Holland (J. L. Holland, D. R. Whitney, N. S. Cole, & J. M. Richards, 1969) themes; (b) gender and career gender‐typing predicted interests in Realistic, Investigative, and Social careers; and (c) perceived parent support accounted for 29% to 43% of the total unique variance in vocational self‐efficacy for all Holland theme careers.     

Expectations, Capital Gains, and Income

A theoretical framework for the measurement of income under uncertainty is developed that addresses some long-standing controversies about the treatment of capital gains. The consequences for economic analysis and policy making are potentially serious, because the treatment of capital gains can significantly affect some major macroeconomic aggregates, including national income and savings, balance of payments deficits, government deficits, and depreciation. (JEL O47 , P44 , Q32 )     

Campus attitudes toward alcohol and drugs in a deep southern university.

In our zeal to deal with alcohol and drug abuse, we may have a distorted picture of what the majority of college students actually think about alcohol and drug use. Students in this study done at a public university located in the Deep South report being generally intolerant of substance abuse.