بهره وری کل عوامل و فرضیه لبریز: برخی شواهد جدید

In this paper I test the spillover hypothesis of the endogenous growth literature on a sample of manufacturing firms in Italy, 1989–1994, using a new approach based on the Malmquist index. First, I measure the productivity growth registered by the high- and non-high-tech firms computing the Malmquist index with DEA. I decompose it into technical change and technical efficiency change. Then I test whether the technical change registered by high-tech firms affects productivity growth of non-high-tech firms, after controlling for factors which can potentially affect productivity growth

The hypothesis that technological knowledge acquired by a firm can spillover to other firms and enhance the latter group's total factor productivity1 was first suggested by Arrow (1962) in his work on the effects of learning embodied in new capital equipment. Since then, there has been a considerable theoretical debate on the extent to which a firm can benefit from spillovers and also how much of its productivity growth such spillovers can explain (Romer, 1986; Grossman and Helpman, 1990; Cohen and Levinthal, 1989).

The existence of knowledge spillovers and to what extent they can have a beneficial effect on firms’ productivity has always been a contentious issue. Some researchers suggest that knowledge produced by innovating firms can be absorbed and used immediately by other firms, enhancing their productivity; however, this view has been criticised by those who claim that a firm has to make a considerable investment in R&D before being able to absorb fruitfully knowledge produced elsewhere.