This paper introduces a novel approach to study the effects of common shocks on panel data models with endogenous explanatory variables when the cross section dimension (N) is large and the time series dimension (T) is fixed: this relies on conditional strong laws of large numbers and...

Building upon the work of Chen et al. (2010), this paper proposes a test for sphericity of the variance–covariance matrix in a fixed effects panel data regression model without the normality assumption on the disturbances.