An augmented neoclassical production function developed by Feder (1982) is used to explore the presence of marginal externality effects of exports and intersectoral factor productivity differentials between exporting and nonexporting sectors. The parametric differences among countries are investigated. We estimate coefficients for marginal externalities of exports and the intersectoral factor productivity differentials using cross-country and panel data for 69 low- and middle-income countries. The fixed and random effects models are used to appraise the existence of parametric differences among the nations. This paper also examines the robustness of the linkages between export-expansion and economic growth by using different levels of aggregation of cross-country and panel data sets
