The spatial structure of county-level agricultural production in China in 1999 is analysed. A convenient simple method that corrects for both spatial autocorrelation and spatial heterogeneity in the input-output relationships using spatial lag models and an allowance for the response...

Heien and Wessells' two-step estimator for the multivariate sample-selection model has been used extensively during the past 15 years. A modified version of it, with slightly different selectivity regressors, has also appeared in the empirical literature. Both estimators are unfounded and...