R and D and absorptive capacity: Theory and empirical evidence

This paper presents a single unified framework that integrates the theoretical literature on Schumpeterian endogenous growth and major strands of the empirical literature on R&D, productivity growth and productivity convergence. Starting from a structural model of endogenous growth following Aghion and Howitt (1992, 1998), we provide microeconomic foundations for the reduced-form equations for total factor productivity (TFP) growth frequently estimated empirically using industry-level data. R&D affects both innovation and the assimilation of others' discoveries ("absorptive capacity"). Long-run cross-country differences in productivity emerge endogenously, and the analysis implies that many existing studies underestimate R&D's social rate of return by neglecting absorptive capacity.