Testing for Unit Roots with Breaks: Evidence on the Great Crash and the Unit Root Hypothesis Reconsidered

Nelson and Plosser (1982), in a classic paper, failed to find strong evidence against the null hypothesis of a generating process with a unit autoregressive root for thirteen US macroeconomic time series. Perron (1989) claimed that such evidence was available for a majority of these series if the alternative hypothesis was of trend stationarity with a break in 1929. Zivot and Andrews (1992) treated the break date as endogenous, then finding strong evidence agcainst the null for a minority of these series. Our own analysis extends theirs by permitting a break under the null as well as the alternative hypothesis, and allowing for the sequential nature of the testing. Our empirical findings complete the circle. We find no strong evidence against the unit root hypothesis for any of the thirteen Nelson–Plosser series.     

Pigouvian Taxes: A Strategic Approach

This paper analyzes the problem of designing mechanisms to implement efficient solutions in economies with externalities. We provide two simple mechanisms implementing the Pigouvian Social Choice Correspondence in environments in which coalitions can or cannot be formed.     

A Model of Elitist Qualification

This paper deals with the collective qualification of members of society as belonging to a certain category or group based on a fixed attribute. Our model contains three main features: the existence of individual gradual opinions, the notion of elitism (only the opinions of certain individuals are taken into account to delineate the reference group), and the idea of sequentiality (elites are successively created by using the previous elites’ opinions on a social decision scheme). The main results of the paper characterize when this sequential procedure converges for some intuitive ways of aggregating individual opinions. Finally, we analyze the role of convergence for two extra basic properties (symmetry and contractiveness) that elitist rules should possess.     

Promoting justice by treating people unequally: an experimental study

Which inequalities among individuals are considered unjust? This paper reports the results of an experiment designed to study distributive choices dealing with arbitrarily unequal initial endowments. In a three-person distribution problem where subjects either know or do not know their endowments, we find impartial behavior to be a stable pattern. Subjects either compensate for initial inequalities fully or not at all in both conditions, and they do so more often when they do not know their endowment than when they know it. Moreover, the type and the size of the good to be distributed also affect the frequency of impartial behavior.     

Herding in the strategic allocations of Spanish pension plan managers

This paper empirically examines herding behavior in the strategic style allocations of Spanish pension plan managers. The study uses both the standard metric used in financial literature to capture institutional herding and a new approach to address some shortcomings of this traditional measure. Concretely, some authors have highlighted that the traditional measure does not take into account that the probability that a manager buys rather than sells a certain stock depends on both the initial holding in the stock and the asset flows. As a consequence, this study proposes a new approach, which can be applied to other financial markets and provides more accurate values of the probability to increase (or decrease) the style exposures bearing in mind the previous exposure of each portfolio. The study confirms the existence of herding behavior by using both methods. Although the strength of this behavior decreases using the new approach, the herding levels detected in this study of style herding of Spanish pension plans are higher than those of previous research analyzing portfolio holdings in other countries. Additionally, herding levels are higher in periods of low volatility while market returns does not seem to influence herding levels.     

External liabilities and crises

We examine the determinants of external crises, focusing on the role of foreign liabilities and their composition. Using a variety of statistical tools and comprehensive data spanning 1970–2011, we find that the ratio of net foreign liabilities to GDP is a significant crisis predictor. This is primarily due to the net position in debt instruments—the effect of net equity liabilities is weaker and net FDI liabilities seem, if anything, an offset factor. We also find that: i) breaking down net external debt into its gross asset and liability counterparts does not add significant explanatory power to crisis prediction; ii) the current account is a powerful predictor; iii) foreign exchange reserves reduce the likelihood of crisis more than other foreign asset holdings; and iv) a parsimonious probit containing those and a handful of other variables has good predictive performance in- and out-of-sample. The latter result stems largely from our focus on external crises sensu stricto.     

Saving in Developing Countries: An Overview

This article reviews the current state of knowledge on the determinantsof saving rates, presenting the main findings and contributionsof the recently completed World Bank research project, ‘SavingAcross the World.’ The article discusses the basic designof the research project and its core database, the World SavingDatabase. It then summarizes the main project results and placesthem in the context of the literature on saving, identifyingthe key policy and nonpolicy determinants of private savingrates. Special attention is paid to the relationship betweengrowth and saving and the impact of specific policies on savingrates. The article concludes by introducing the studies includedin this special issue.     

Carbon sequestration and farm income in West Africa: Identifying best management practices for smallholder agricultural systems in northern Ghana

The interest in agricultural soils as global storage of carbon has increased in recent years, along with the prospect of farmers' participation in payment schemes under the Clean Development Mechanism of the Kyoto protocol. Thus, a better understanding of agricultural practices that can increase soil carbon and enhance the livelihoods of farmers is necessary, particularly in smallholder farming systems of West Africa. This study evaluates different crop management strategies both by their capacity to sequester carbon in agricultural soils and by their contribution to household income. A case study in Wa, Upper West Region of Ghana is used to test 48 different cropping strategies by means of a crop simulation model and a household-level multiple-criteria optimisation model. Each cropping strategy is evaluated after a 20-year simulation period by its capacity to accrue carbon in the soil, by its economic performance at the plot-level, and by its contribution to the farm income with and without carbon payments. A set of best management practices that concomitantly increase soil carbon and farm income are identified and classified by their cost of investment.     

Behavioral agency and corporate entrepreneurship: CEO equity incentives & competitive behavior

Scholars have long studied drivers of entrepreneurial behavior among established firms. Yet little is known about how individual factors shape a firm’s choice to pursue entrepreneurship. We draw on behavioral agency theory to explore the role of equity incentives in driving corporate entrepreneurship. Our findings suggest CEOs avoid corporate entrepreneurial behaviors as their option wealth increases. However industry dynamics also prove to be an important contingency when predicting the effects of both restricted stock and stock options on the likelihood that the CEO engages in corporate entrepreneurship. Our findings provide a theoretical platform for predicting dimensions of entrepreneurial behavior and highlight effects of CEO equity ownership.