This paper introduces and analyses a setting with general heterogeneity in regression modelling. It shows that regression models with fixed or time-varying parameters can be estimated by OLS or time-varying OLS methods, respectively, for a very wide class of regressors and noises, not covered by...

In a systematic review and meta-analysis, Wang et al. (2023) estimate the association of social isolation or loneliness with mortality outcomes. In their preferred analytical specification, the authors find an increased risk of mortality from all causes for both exposures: a pooled effect size...