Do we reject too often?: Small sample properties of tests of rational expectations models

We examine the small sample properties of tests of rational expectations models. We show using Monte Carlo experiments that the asymptotic distribution of test statistics can be extremely misleading when the time series examined are highly autoregressive. In particular, a practitioner relying on the asymptotic distribution will reject true models too frequently. We also show that this problem is especially severe with detrended data. We present correct small sample critical values for our canonical problem.     

News shocks or parametric indeterminacy? An observational equivalence result in linear rational expectations models

This paper studies identification in linear rational expectations models with news shocks. We show that news-driven models and indeterminate equilibrium economies with i.i.d. fundamentals are observationally equivalent. This finding calls for carefully designing empirical investigations of news shocks in estimated DSGE models.     

How do advertised brands benefit from private labels? An application of rational expectations models

Private labels have traditionally been viewed as a threat to advertised brands. Contrary to traditional wisdom, this study uses a two-asset rational expectations model to show that advertised brands could benefit from private labels. While the manufacturer’s advertising creates product differentiation, the retailer’s synchronous pricing strategy further enhances the product differentiation and raises profits as well as the efficiency of price discounts for the advertised brand. In addition, the existence of private labels improves the advertising efficiency, especially for newly introduced brands. The economic role of private labels is not limited to taking a free ride on the manufacturer’s advertising efforts, and this role cannot be replaced by another advertised brand.     

Environmental efficiency and labour productivity: Trade-off or joint dynamics? A theoretical investigation and empirical evidence from Italy using NAMEA

In this paper we test an adapted EKC hypothesis to verify the relationship between ‘environmental efficiency’ (namely emissions per unit of value added) and labour productivity (value added per employee). We exploit NAMEA data on Italy for 29 sector branches and 6 categories of air emissions for the period 1991-2001. We employ data on capital stock and trade openness to test the robustness of our results.On the basis of the theoretical and empirical analyses focusing on innovation, firm performances and environmental externalities, we would expect a positive correlation between environmental efficiency and labour productivity — a negative correlation between the emissions intensity of value added and labour productivity — which departs from the conventional mainstream view. The hypothesis tested is a critical one within the longstanding debate on the potential trade-off or complementarity between environmental preservation and economic performance, which is strictly associated with the role of technological innovation. We find that for most air emission categories there is a positive relationship between labour productivity and environmental efficiency. Labour productivity dynamics, then, seem to be complementary to a decreasing emissions intensity in the production process. Taking a disaggregate sector perspective, we show that the macro-aggregate evidence is driven by sector dynamics in a non-homogenous way across pollutants. Services tend always to show a ‘complementary’ relationship, while industry seems to be associated with inverted U-shape dynamics for greenhouse gases and nitrogen oxides. This is in line with our expectations. In any case, EKC shapes appear to drive such productivity links towards complementarity. The extent to which this evidence derives from endogenous market forces, industrial and structural change, and policy effects is discussed by taking an evolutionary perspective to innovation and by referring to impure public goods arguments.