Generalized additive mixed models

Following the extension from linear mixed models to additive mixed models, extension from generalized linear mixed models to generalized additive mixed models is made, Algorithms are developed to compute the MLE's of the nonlinear effects and the covariance structures based on the penalized marginal likelihood. Convergence of the algorithms and selection of the smooth param¬eters are discussed.     

Does the Family and Medical Leave Act (FMLA) Increase Fertility Behavior?

The Family and Medical Leave Act (FMLA), implemented in August 1993, grants job-protected leave to any employee satisfying the eligibility criteria. One of the provisions of the FMLA is to allow women to stay at home for a maximum period of 12 weeks to give care to the newborn. The effect of this legislation on the fertility response of eligible women has received little attention by researchers. This study analyzes whether the FMLA has influenced birth outcomes in the U.S. Specifically, I evaluate the effect of the FMLA by comparing the changes in the birth hazard profiles of women who became eligible for FMLA benefits such as maternity leave, to the changes in the control group who were not eligible for such leave. Using a discrete-time hazard model, results from the difference-in-differences estimation indicate that eligible women increase the probability of having a first and second birth by about 1.5 and 0.6 % per annum, respectively. Compared to other women, eligible women are giving birth to the first child a year earlier and about 8.5 months earlier for the second child.     

Institutional Diversity and Performance in African Cotton Sectors

This article analyses the performance of cotton sectors across East, Southern, and West Africa, paying particular attention to the wide diversity of institutional arrangements that they now exhibit. It finds strong support for earlier contentions regarding trade‐offs between competition and coordination, and between the roles of public and private sectors. New insights provide concrete and context‐specific guidance to policy‐makers and stakeholders regarding the key challenges they will face and the risks they will need to manage as they work to improve productivity and ensure an equitable division of benefits within cotton sectors.