Working papers results

Recent financial research has provided evidence on the predictability of asset returns. In this paper we consider the results contained in Pesaran-Timmerman(1995), which provided evidence on predictability over the sample 1959-1992. We show that the extension of the sample to the ninetie weakens considerably the statistical and economic significance of the predictability of stock returns based on earlier data. We propose an extension of their framework, based on the explicit consideration of model uncertainty under rich parameterizations for the predictive models.
We propose a novel methodology to deal with model uncertainty based on thick modeling, i.e. on considering a multiplicity of predictive models rather than a single predictive model. We show that portfolio allocations based on a thick modelling strategy sistematically overperforms thin modelling.

Recent empirical evidence suggests a negative relationship between trade integration and income per capita convergence. We show that moderate reductions in trade posts can generate sizable increases in income per capita divergence in a neoclassical two-country model of trade and growth. The welfare of both countries, however, rises with trade integration due to changes in their consumption time paths. Our setup sheds light on the striking nonlinear growth in the trade share of output since World War II: a linear fall in trade costs over time produces an exponential increase in the trade share of GDP. Concerning the empirical relationship between openness and technological progress, we perform an exercise that cautions against the use of aggregate production functions to obtain Solow residuals: two countries that reduce their trade costs and experience no technological progress are measured to have positive TFP growth rates if an aggregate production function is used for that purpose.

A feature of new economic geography model is their mathematical intractability. This intractability results from the fact that the functional relationship between the indirect utility differential and the state variable cannot be found explicitly. We illustrate three methods that can be utilized to approximate the unknown function. These methods are simple and give a remarkable improvement in the precision of approximation with respect to the commonly utilized Lagrange approximation. Precision of approximation is important in models that feature catastrophic behavior. We apply these methods to the core-periphery model. Naturally, they can be applied to all cases of unknown functional relationships.

The creation of Europes new stock markets represents a major experiment in market design with important implications for the ability to support innovative, fast-growing companies. We evaluate the success of these markets based on a large number of measures of firm performance and strategy which extend to several pre- and post-listing years. Our hand collected databasemis obtained from the listing prospectuses and annual reports of 538 companies which listed on the Neuer Markt, Nouveau March, and Nuovo Mercato from 1996 through 2001. Three findings stand out. First, these companies experience a dramatic change after the IPO, rebalancing their capital structure, increasing their debt and investment, accelerating growth, and becoming less profitable. These changes are consistent with the existence of credit constraints, and are greater than for companies listing on the main markets. Second, we document a considerable variation in post-IPO growth rates and corporate strategy, across both companies and markets. This variation is largely due to the ability to raise equity capital at IPO. Third, the adoption of US GAAP accounting standards substantially increases firms ability to raise capital. While Europes new markets have provided high-growth companies with an unprecedented opportunity to finance their growth, the adoption (and enforcement) of tighter standards of disclosure is then crucial for their success.

In a Common Currency Area (CCA) the Common Central Bank sets a uniform rate of inflation across countries, taking into account the areas economic conditions. Suppose that countries in recession favor a more expansionary policy than countries in expansion, a conflict of interest between members arises when national business cycles are not fully synchronized. If governments of member countries have an informational advantage over the state of their domestic economy, such conflict may create an adverse selection problem: national authorities overemphasize their shocks, in order to shape the common policy towards their needs. This creates an inefficiency over and above the one-policy-fits-all cost discussed in the optimal currency area literature. In order to minimize this extra-burden of asymmetric information, monetary policy must over-react to large symmetric shocks and under-react to small asymmetric ones. The result is sub-optimal volatility of inflation.

After the creation of the European Monetary Union (EMU), both the European Commission (EC) and the European Central Bank (ECB) are focusing more and more on the evolution of the EMU as a whole, rather than on single member countries. A particularly relevant issue from a policy point of view is the availability of reliable forecasts for the key macroeconomic variables. Hence, both the fiscal and the monetary authorities have developed aggregate forecasting models, along the lines previously adopted for the analysis of single countries. A similar approach will be likely followed in empirical analyses on, e.g., the existence of an aggregate Taylor rule or the evaluation of the aggregate impact of monetary policy shocks, where linear specifications are usually adopted. Yet, it is uncertain whether standard linear models provide the proper statistical framework to address these issues. The process of aggregation across countries can produce smoother series, better suited for the analysis with linear models, by averaging out country specific shocks. But the method of construction of the aggregate series, which often involves time-varying weights, and the presence of common shocks across the countries, such as the deflation in the early 1980s and the convergence process in the early 1990s, can introduce substantial non-linearity into the generating process of the aggregate series. To evaluate whether this is the case, we fit a variety of non-linear and time-varying models to aggregate EMU macroeconomic variables, and compare them with linear specifications. Since non-linear models often over-fit in sample, we assess their performance in a real time forecasting framework. It turns out that for several variables linear models are beaten by non-linear specifications, a result that questions the use of standard linear methods for forecasting and modeling EMU variables.

 

 

The aim of this paper is to estimate the effect of research externalities across space, in generating innovation.We do so by using R&D and patent data for eighty-six European Regions in the 1977-1995 period. We find that spillovers exist for regions within a distance of 300 Km from each other. The estimates are robust to simultaneity, omitted variable bias, different specifications of distance functions, country and border effects. The size of these spillovers is small, though. Doubling R&D spending in a region would increase the output of new ideas in other regions within 300 Km only by 2-3%, while it would increase the innovation of the region itself by 80-90%. Given the small size and the limited range of diffusion, we interpret these externalities as the result of local diffusion of non-codified knowledge, embodied in people and spreading via personal contacts. This interpretation is reinforced by the finding that the spillovers are somewhat weaker across national borders.

The objective of this study is to investigate the behaviour of monetary and fiscal authorities in the Euro area. Our main contribution is joint modelling of behaviour of the two authorities. Our investigation highlights a number of facts. The systematic monetary policies adopted by the non-German authorities in the seventies were not capable of stabilizing inflation. Such results have been achieved in the eigthies and the nineties by anchoring more tightly domestic monetary policy to German monetary policy. All the main episodes of expansionary fiscal policy occurred in the course of the eigthies and the nineties in Europe cannot be explained by the sytematic behaviour of fiscal authorities. Stabilization of inflation has been achieved independently from the lack of fiscal discipline. There are important interactions between the two authorities but they depend exclusively on the responses of governemnts expenditures and receipts to interest rate payments on the public debt.

Revised version: June 28, 2002

Despite the fast catching-up in ICT diffusion experienced by most EU countries in the last few years, information technologies have so far delivered little productivity gains in Europe. In the second half of the past decade, the growth contributions from ICT capital rose in six EU countries only (the UK, Denmark, Finland, Sweden, Ireland and Greece). Quite unlike the United States, this has not generally been associated to higher labour or total factor productivity growth rates, the only exceptions being Ireland and Greece. Particularly worrisome, the large countries in Continental Europe (Germany, France, Italy and Spain) showed stagnating or mildly declining growth contributions from ICT capital, together with definite declines in TFP growth compared to the first half of the 1990s. It looks like that the celebrated Solow paradox on the lack of correlation between ICT investment and productivity growth has fled the US to migrate to Europe.

It is rather common to have several competing forecasts for the same variable, and many methods have been suggested to pick up the best, on the basis of their past forecasting performance. As an alternative, the forecasts can be combined to obtain a pooled forecast, and several options are available to select what forecasts should be pooled, and how to determine their relative weights. In this paper we compare the relative performance of alternative pooling methods, using a very large dataset of about 500 macroeconomic variables for the countries in the European Monetary Union. In this case the forecasting exercise is further complicated by the short time span available, due to the need of collecting a homogeneous dataset. For each variable in the dataset, we consider 58 forecasts produced by a range of linear, time-varying and non-linear models, plus 16 pooled forecasts. Our results indicate that on average combination methods work well. Yet, a more disaggregate analysis reveals that single non-linear models can outperform combination forecasts for several series, even though they perform rather badly for other series so that on average their performance is not as good as that of pooled forecasts. Similar results are obtained for a subset of unstable series, the pooled forecasts behave only slightly better, and for three key macroeconomic variables, namely, industrial production, unemployment and inflation.