Bivariate duration data frequently arise in economics, biostatistics and other areas. In bivariate frailty models, dependence between the frailties (i.e., unobserved determinants) induces dependence between the durations. Using notions of quadrant dependence, we study restrictions that this...

In their IZA Discussion Paper 10247, Johansson and Lee claim that the main result (Proposition 3) in Abbring and Van den Berg (2003b) does not hold. We show that their claim is incorrect. At a certain point within their line of reasoning, they make a rather basic error while transforming one...

From individual-level longitudinal data for two entire cohorts of medical students in UK universities, we analyse the probability that an individual student will ?drop out? of medical school prior to the successful completion of their studies. We examine the cohort of students enrolling for a...

We examine a new general class of hazard rate models for survival data, containing a parametric and a nonparametric component. Both can be a mix of a time effect and (possibly time-dependent) marker or covariate effects. A number of well-known models are special cases. In a counting process...

Different theoretical explanations suggest that worker-managed firms (WMFs) are prone to failure in competitive environments. Using a long panel of Uruguayan firms, the author presents new evidence on firm survival comparing WMFs and conventional firms. Excluding microenterprises and controlling...

We examine a new general class of hazard rate models for survival data, containing a parametric and a nonparametric component. Both can be a mix of a time effect and (possibly time-dependent) marker or covariate effects. A number of well-known models are special cases. In a counting process...

Different theoretical explanations suggest that worker-managed firms (WMFs) are prone to failure in competitive environments. Using a long panel of Uruguayan firms, the author presents new evidence on firm survival comparing WMFs and conventional firms. Excluding microenterprises and controlling...

Bivariate duration data frequently arise in economics, biostatistics and other areas. In "bivariate frailty models", dependence between the frailties (i.e., unobserved determinants) induces dependence between the durations. Using notions of quadrant dependence, we study restrictions that this...