Inter-basin water transfers under uncertainty: Storage capacity and optimal guaranteed deliveries

This paper deals with water transfers between jurisdictions not claiming riparian rights to the same water source, and taking place through straightforward sales. Taking into account the uncertain nature of water surpluses, we investigate, within a partial equilibrium framework, the implications of a third party's provision of storing facilities upon the potential supplier's decision whether, and to what extent, it is worthwhile to guarantee a constant amount of water exports. The analysis suggests that there exists a minimum storage capacity below which the potential supplier will never find it profitable to divert a constant amount of water outside his boundaries; the greater the uncertainty about future surpluses and/or internal costs due to even occasional water shortages resulting from the water export commitment, the higher the required minimum storage capacity will be. Above this minimum, an increase in the capacity would be better for the surplus agent, but in a situation in which water surplus is expected to decrease over time, increases in storage capacity would make him willing to guarantee a smaller amount of water deliveries.This work has been carried out under the auspices of the European Science Foundation's research program Sharing fresh water resources in the Mediterranean region: An economic perspective. Previous versions have been presented at ESF workshops held at the Universities of Haifa, Padova and Crete. Financial support from MURST (funds 40% — 1992) is gratefully acknowledged. We wish to thank Nunzio Cappuccio, Haluk Akdogan, Karl Mäler, Mordechai Shechter, Naomi Zeitouni, and two anonimous referees for helpful comments. The usual disclaimer applies.     

Assessing students’ equality of opportunity in OECD countries: the role of national- and school-level policies

This article analyses the relationship between equality of opportunity and the characteristics of the educational system, jointly considering country- and school-level policies. Because school social environment represents a fundamental channel in shaping educational opportunities, we consider all policies, recorded in PISA 2012 dataset, that affect the sorting of students to schools. We show that including sorting policies enriches the explanation of the socio-economic gradient, that is, the association between students’ performances and parental background, with respect to previous studies including only country-level features. The negative impact of early tracking on equality of opportunity is overvalued without including other sorting policies, while grouping students’ within-school by ability increases the socio-economic gradient and a greater students’ heterogeneity in the school reduces the gradient.     

Technological regimes and demand structure in the evolution of the pharmaceutical industry

This paper examines how the nature of the technological regime governing innovative activities and the structure of demand interact in determining market structure, with specific reference to the pharmaceutical industry. The key question concerns the observation that—despite high degrees of R&D and marketing-intensity—concentration has been consistently low during the whole evolution of the industry. Standard explanations of this phenomenon refer to the random nature of the innovative process, the patterns of imitation, and the fragmented nature of the market into multiple, independent submarkets. We delve deeper into this issue by using an improved version of our previous “history-friendly” model of the evolution of pharmaceuticals. Thus, we explore the way in which changes in the technological regime and/or in the structure of demand may generate or not substantially higher degrees of concentration. The main results are that, while technological regimes remain fundamental determinants of the patterns of innovation, the demand structure plays a crucial role in preventing the emergence of concentration through a partially endogenous process of discovery of new submarkets. However, it is not simply market fragmentation as such that produces this result, but rather the entity of the “prize” that innovators can gain relative to the overall size of the market. Further, the model shows that emerging industry leaders are innovative early entrants in large submarkets.     

When do improved covariance matrix estimators enhance portfolio optimization? An empirical comparative study of nine estimators

The use of improved covariance matrix estimators as an alternative to the sample estimator is considered an important approach for enhancing portfolio optimization. Here we empirically compare the performance of nine improved covariance estimation procedures using daily returns of 90 highly capitalized US stocks for the period 1997–2007. We find that the usefulness of covariance matrix estimators strongly depends on the ratio between the estimation period T and the number of stocks N, on the presence or absence of short selling, and on the performance metric considered. When short selling is allowed, several estimation methods achieve a realized risk that is significantly smaller than that obtained with the sample covariance method. This is particularly true when T/N is close to one. Moreover, many estimators reduce the fraction of negative portfolio weights, while little improvement is achieved in the degree of diversification. On the contrary, when short selling is not allowed and T?>?N, the considered methods are unable to outperform the sample covariance in terms of realized risk, but can give much more diversified portfolios than that obtained with the sample covariance. When T?<?N, the use of the sample covariance matrix and of the pseudo-inverse gives portfolios with very poor performance.     

The anticipated and concurring effects of the EMU: exchange rate volatility, institutions and growth

Reduced exchange rate volatility and higher and less heterogeneous quality of institutional rules and macroeconomic policies are two of the main (anticipated and concurring) effects expected from a currency union.In this paper, we measure the magnitude of these two effects for the Eurozone countries looking at real effective exchange rates (REER) and at different indicators of quality of institutional rules and macroeconomic policies (QIRMP). We find that the first effect is much stronger than the second when we compare relative changes for Eurozone countries and the rest of the world in the relevant period.We further evaluate the impact of both effects on economic growth on a larger sample of countries. Our findings show that both have significant impact on levels (more robust) and on rates of growth (weaker) of per capita GDP.     

Intergenerational Earnings Inequality: New Evidence From Italy

Using an innovative dataset built by merging survey and administrative data, we provide new estimates of intergenerational earnings’ inequality between fathers and sons in Italy, extending previous evidence in several directions. We rely on the TSTSLS method to predict fathers’ earnings and compute intergenerational elasticities and imputed rank–rank slopes, trying to reduce estimation biases. Confirming previous evidence, we find that Italy is characterized by a high intergenerational inequality in cross-country comparison. Extending previous analyses, we show that the intergenerational association increases when sons at older ages and multi-annual averages of pseudo-fathers’ and sons’ earnings are considered. We also find that the intergenerational persistence differs across geographical macro-areas and is high also for daughters, especially when family earnings are considered. Furthermore, estimates where possible mediating factors of the parental influence are included among the covariates show that a high intergenerational association persists when sons’ education and occupation are controlled for.     

Analysts’ annual earnings forecasts and changes to the I/B/E/S database

Review of Accounting Studies - I/B/E/S is a common source of analyst earnings forecast data, and the reliability of these data is important for practice and academic research. Examining a common...