This paper presents a survey of the micro-econometric literature on the effects of R&D tax credits on firms' innovation activities. We focus on one specific aspect that has not received sufficient attention in previous research: the sectoral dimension. Our meta-regression analysis (MRA) sets up a new database collecting a large number of firm-level studies on the effects of R&D tax credits and investigates the factors that may explain differences in the estimated effects that are reported in the literature. The main result of the MRA analysis is indeed that sectors matter. Micro-econometric studies that have focused on a sub-sample of high-tech industries have on average obtained a smaller estimated effect of R&D tax credits. The paper proposes a simple framework to investigate why the effects of R&D tax credits vary across sectors and points out new directions and hypotheses for future research.JEL codes: O1, O3, O4

Do the additionality effects of R&D tax credits vary across sectors? The paper presents a microeconometric analysis of this question for three countries: Norway, Italy and France. We use a panel of firm-level data from three waves of the Innovation Surveys carried out in these countries for 2004, 2006 and 2008. The study estimates input and output additionality effects of R&D tax credits in each of these economies, and it investigates how these effects differ across sectors characterized by different R&D orientation and competition conditions. The results point out that firms in industries with high R&D orientation have on average higher propensity to apply to R&D fiscal incentives schemes and stronger input and output additionality effects. Output additionality is found to differ among the three examined countries.