One- and two-center physical space partitioning of the energy in the density functional theory

A conceptually new approach is introduced for the decomposition of the molecular energy calculated at the density functional theory level of theory into sum of one- and two-atomic energy components, and is realized in the "fuzzy atoms" framework. (Fuzzy atoms mean that the three-dimensional physical space is divided into atomic regions having no sharp boundaries but exhibiting a continuous transition from one to another.) The new scheme uses the new concept of "bond order density" to calculate the diatomic exchange energy components and gives them unexpectedly close to the values calculated by the exact (Hartree-Fock) exchange for the same Kohn-Sham orbitals

Fronts from complex two-dimensional dispersal kernels: theory and application to Reid's paradox

Bimodal dispersal probability distributions with characteristic distances differing by several orders of magnitude have been derived and favorably compared to observations by Nathan [Nature (London) 418, 409 (2002)]. For such bimodal kernels, we show that two-dimensional molecular dynamics computer simulations are unable to yield accurate front speeds. Analytically, the usual continuous-space random walks (CSRWs) are applied to two dimensions. We also introduce discrete-space random walks and use them to check the CSRW results (because of the inefficiency of the numerical simulations). The physical results reported are shown to predict front speeds high enough to possibly explain Reid's paradox of rapid tree migration. We also show that, for a time-ordered evolution equation, fronts are always slower in two dimensions than in one dimension and that this difference is important both for unimodal and for bimodal kernels

Rational Partisan Theory with fiscal policy and an independent central bank

The empirical evidence testing the validity of the rational partisan theory (RPT) has been mixed. In this article, we argue that the inclusion of other macroeconomic policies and the presence of an independent central bank can partly contribute to explain this inconclusiveness. This article expands Alesina s (1987) RPT model to include an extra policy and an independent central bank. With these extensions, the implications of RPT are altered signi ficantly. In particular, when the central bank is more concerned about output than public spending (an assumption made by many papers in this literature), then the direct relationship between in flation and output derived in Alesina (1987) never holds. Keywords: central bank, conservativeness, political uncertainty. JEL Classi fication: E58, E63.

Finding a suitable job: the effect of the institutional context on self-perceived over-education

The current research compares the perception of over-education in four different European countries, resorting to European Household Panel Data. The results confirm that the type of educational system accounts for some of the cross-national differences in self-perceived over-education. In qualificational spaces, like Denmark, where vocational training receives more importance, self-perceived over-education is not associated as much with educational attainment as in the so-called’ organisational spaces’, like Spain, France and Italy. Yet, the results confirm that, controlling for the system of education, the traits and regulation of the labour market also have an effect on over-education. Thus, in Spain, where temporary employment has soared in recent decades, this type of contract is clearly associated with the perception of over-education, to a much higher extent than in Italy or France. Temporary contracts in Spain may not work as a steppig stone for attaining a job suitable to the training received by the individual, as they may in the case of France or Italy. In sum, not only institutions offering skills and human capital, but labour market regulation as well, have a clear impact on the incidence of over-education.

Revealing the dark side of traditional democracies in plurinational societies. The case of Catalonia and the Spanish “Estado de las Autonomías”

In this article, I firstly offer a synthesis of a brief set of analytical elements of the theory of democracy and federalism established in the recent debate which identify a number of flaws in the normative and institutional bases of plurinational democracies. It is necessary to overcome these flaws in order to achieve a true political and constitutional recognition and accommodation of the national pluralism of this kind of liberal democracies (section 1). Secondly, we will focus on the Spanish case of the “Estado de las Autonomías” taking into account the recent reform of the Catalan constitutional law (Estatut d’autonomia 2006) (section 2). A final section makes a number of concluding remarks relating the previously highlighted elements of the theory of democracy and federalism with the analysis of the Catalan case (section 3).

Theorizing institutional changes: understanding decentralization and federalization in Brazil, Spain and South Africa

In light of the existing theories about institutional change, this paper seeks to advance a common framework to understand the unfolding of decentralization and federalization in three countries: Brazil, Spain, and South Africa. Although in different continents, these three countries witnessed processes after their respective transitions to democracy that transferred administrative and fiscal authority to their regions (decentralization) and vertically distributed political and institutional capacity (federalization). This paper attempts to explain how institutional changes prompted a shift of power and authority towards regional governments by looking at internal sources of change within the intergovernmental arena in the three countries. This analysis is organized around two propositions: that once countries transit to democracy under all-encompassing constitutions there are high incentives for institutional change, and that under a bargained intergovernmental interaction among political actors subnational political elites are able to advance their interests incrementally. In short, through a common framework this paper will explain the evolving dynamics of intergovernmental dynamics in three countries.

The Big Band Theory : català col·loquial i humor científic. Proposta de traducció del capítol pilot

Aquest treball elabora una proposta de traducció per al doblatge del capítol pilot de The Big Bang Theory, que combina llenguatge col•loquial i llenguatge científic.L’objectiu és doble: elaborar un llenguatge col•loquial creïble però a la vegada genuí i emprar els equivalents catalans adequats per als termes científics originals.

Capital, Wages, and Growth: Theory and Evidence

Returns to scale to capital and the strength of capital externalities play a key role for the empirical predictions and policy implications of different growth theories. We show that both can be identified with individual wage data and implement our approach at the city-level using US Census data on individuals in 173 cities for 1970, 1980, and 1990. Estimation takes into account fixed effects, endogeneity of capital accumulation, and measurement error. We find no evidence for human or physical capital externalities and decreasing aggregate returns to capital. Returns to scale to physical and human capital are around 80 percent. We also find strong complementarities between human capital and labor and substantial total employment externalities.

Measurement with Some Theory: a New Approach to Evaluate Business Cycle Models

We propose a method to evaluate cyclical models which does not require knowledge of the DGP and the exact empirical specification of the aggregate decision rules. We derive robust restrictions in a class of models; use some to identify structural shocks and others to evaluate the model or contrast sub-models. The approach has good size and excellent power properties, even in small samples. We show how to examine the validity of a class of models, sort out the relevance of certain frictions, evaluate the importance of an added feature, and indirectly estimate structural parameters.

Social Security in Theory and Practice (II): Efficiency Theories, Narrative Theories, and Implications for Reform

166 countries have some kind of public old age pension. What economic forces create and sustain old age Social Security as a public program? Mulligan and Sala-i-Martin (1999b) document several of the internationally and historically common features of social security programs, and explore "political" theories of Social Security. This paper discusses the "efficiency theories", which view creation of the SS program as a full of partial solution to some market failure. Efficiency explanations of social security include the "SS as welfare for the elderly" the "retirement increases productivity to optimally manage human capital externalities", "optimal retirement insurance", the "prodigal father problem", the "misguided Keynesian", the "optimal longevity insurance", the "government economizing transaction costs", and the "return on human capital investment". We also analyze four "narrative" theories of social security: the "chain letter theory", the "lump of labor theory", the "monopoly capitalism theory", and the "Sub-but-Nearly-Optimal policy response to private pensions theory". The political and efficiency explanations are compared with the international and historical facts and used to derive implications for replacing the typical pay-as-you-go system with a forced savings plan. Most of the explanations suggest that forced savings does not increase welfare, and may decrease it.

Policy Making in Divided Government. A Pivotal Actors Model with Party Discipline.

This article presents a formal model of policy decision-making in an institutional framework of separation of powers in which the main actors are pivotal political parties with voting discipline. The basic model previously developed from pivotal politics theory for the analysis of the United States lawmaking is here modified to account for policy outcomes and institutional performances in other presidential regimes, especially in Latin America. Legislators' party indiscipline at voting and multi-partism appear as favorable conditions to reduce the size of the equilibrium set containing collectively inefficient outcomes, while a two-party system with strong party discipline is most prone to produce 'gridlock', that is, stability of socially inefficient policies. The article provides a framework for analysis which can induce significant revisions of empirical data, especially regarding the effects of situations of (newly defined) unified and divided government, different decision rules, the number of parties and their discipline. These implications should be testable and may inspire future analytical and empirical work.

Asessing public policies. The case of education in Europe and the interaction between personal and institutional factors

The paper deals with the comparative study of European citizens' satisfaction with the state of education in their respective countries. Individual and contextual effects are tested applying multilevel analysis. The results show that educational public policies (level of decentralization, degree of comprehensiveness and public spending) as well as the students' social environment (socioeconomic and cultural status) have a sound impact on the opinions about the state of education.

Salience theory of choice under risk

We present a theory of choice among lotteries in which the decision maker's attention is drawn to (precisely defined) salient payoffs. This leads the decision maker to a context-dependent representation of lotteries in which true probabilities are replaced by decision weights distorted in favor of salient payoffs. By endogenizing decision weights as a function of payoffs, our model provides a novel and unified account of many empirical phenomena, including frequent risk-seeking behavior, invariance failures such as the Allais paradox, and preference reversals. It also yields new predictions, including some that distinguish it from Prospect Theory, which we test.

How Doing Business Jeopardizes Institutional Reform

Simplifying business formalization and eliminating outdated formalities is often a good way of improving the institutional environment for firms. Unfortunately, the World Bank's Doing Business project is harming such policies by promoting a reform agenda that gives them priority even in countries lacking functional business registers, so that the reformed registers keep producing valueless information, but faster. Its methodology also promotes biased measurements that impede proper consideration of the essential tradeoffs in the design of formalization institutions. If Doing Business is to stop jeopardizing its true objectives and contribute positively to scientific progress, institutional reform and economic development, then its aims, governance and methodology need to change.

A theory of optimal random crackdowns

An incentives based theory of policing is developed which can explain the phenomenon of random “crackdowns,” i.e., intermittent periods of high interdiction/surveillance. For a variety of police objective functions, random crackdowns can be part of the optimal monitoring strategy. We demonstrate support for implications of the crackdown theory using traffic data gathered by the Belgian Police Department and use the model to estimate the deterrence effectof additional resources spent on speeding interdiction.