Semi-endogenous Versus Schumpeterian Growth Models: A Critical Review of the Literature and New Evidence

Several studies have tested semi-endogenous versus Schumpeterian growth models using different methodological approaches. This paper critically reviews these studies including their approaches and provides new evidence on this issue, by analyzing both time-series data from the United States and panel data from 19 OECD countries over the period 1980–2014. The review finds much support for Schumpeterian growth theory, but shows that all studies reviewed have several limitations. These limitations include conceptual problems associated with the use of the number/stock of patents as a measure of the flow/stock of knowledge, the possibility of spurious regressions due to non-stationary data, potential mismeasurement of R&D inputs due to possible interpolation and deflation errors, misspecification problems that can arise in difference models when variables are cointegrated, and potential spurious rejections of the unit root hypothesis for R&D intensity when the lag length in unit root tests is too small. The present study avoids these limitations and finds strong evidence in favor of semi-endogenous growth.