مقاله انگلیسی رایگان در مورد اثر رشد بلند مدت سیاست تحقیق و توسعه – الزویر 2017

مقاله سال 2017

Do changes in public policies aimed at stimulating business R&D lead to higher growth rates of productivity? If any, are these effects long lasting? Taking Schumpeterian growth theory as guideline, this paper addresses these questions by providing econometric evidence on the long-run impact of R&D policy on productivity growth of the United States.

Early models of R&D-based growth postulate that the longrun growth rate of productivity is proportional to the level of research undertaken in the overall economy (see, e.g., Romer, 1990; Grossman and Helpman, 1991; Aghion and Howitt, 1992). In these models, any policy change permanently affects the growth rate of productivity. In the mid-1990s, the critique formulated by Jones (1995b) againstthe prediction ofthese models on the scale effect of R&D stimulated the development of an array of second-generation growth models without scale effects. A first strand of studies makes the assumption of diminishing returns to knowledge and predicts that the steady-state level of productivity is an increasing function of the economy’s size (and hence of the amount of R&D), ∗ Corresponding author. E-mail addresses: antonio.minniti@unibo.it (A. Minniti), francesco.venturini@unipg.it (F. Venturini). but not its growth rate. Accordingly, R&D policy has no impact on productivity growth in the long run, but only along the transition path. These models are referred to as of semi-endogenous growth as they contend that the growth rate of productivity is ultimately driven by the (exogenous) population growth rate (Jones, 1995a; Kortum, 1997; Segerstrom, 1998). Another line of research known as fully-endogenous growth theory (see, e.g., Dinopoulos and Thompson, 1998; Peretto, 1998; Young, 1998; Aghion and Howitt, 2008, ch. 12) builds upon the insight that, as an economy grows and new varieties are discovered, aggregate R&D effort becomes less effective because it spreads among a greater number of product lines. Productivity growth would depend on the R&D intensity at the firm level, explaining why growth can be stationary despite the increasing resources invested in R&D. Accordingly, any policy that affects R&D intensity has also an impact on the steady-state growth rate.

The present paper empirically assesses the long-run growth effect of public policies to business R&D in the US economy using a framework based on the latest strands of Schumpeterian growth theory. Our analysis is carried out in a dynamic panel data setting on twenty US manufacturing industries over the 1975–2000 period. Following the influential studies on tax changes and economic growth (see Lee and Gordon, 2005 and subsequent works), we estimate a growth equation which includes R&D policy instruments as explanatory variables, together with other growth determinants as suggested by the second-generation Schumpeterian growth models. We consider R&D tax credit and the proportion of direct (federal) funding on business R&D expenses as policy variables. The empirical model is estimated by means of a novel regression technique, the Cross-Sectionally Augmented Distributed Lags (CSDL) estimator (Chudik et al., 2016). This approach is based on a dynamic representation which provides consistent estimates for the long-run parameters and is robust along a number of important dimensions (namely, misspecification of dynamics, error serial correlation, cross-sectional dependence, etc.).