Concurrence of water and food insecurities, 25 low- and middle-income countries.

Objective: To investigate how water and food insecurity were associated in nationally representative samples of individuals from 25 low- and middle-income countries.

Methods: We used data from the 2020 World Gallup Poll in which the Individual Water Insecurity Experiences Scale and the Food Insecurity Experience Scale had been administered to 31 755 respondents. These scales measure insecurity experiences in the previous 12 months.

Longitudinal quantile regression in the presence of informative dropout through longitudinal-survival joint modeling.

We propose a joint model for a time-to-event outcome and a quantile of a continuous response repeatedly measured over time. The quantile and survival processes are associated via shared latent and manifest variables. Our joint model provides a flexible approach to handle informative dropout in quantile regression.

Robust estimation for the Cox regression model based on trimming.

We propose a robust Cox regression model with outliers. The model is fit by trimming the smallest contributions to the partial likelihood. To do so, we implement a Metropolis-type maximization routine, and show its convergence to a global optimum.