Testing I(1) against I(d) alternatives in the presence of deteministic components

This paper discusses the role of deterministic components in the DGP and in the auxiliary regression model which underlies the implementation of the Fractional Dickey-Fuller (FDF) test for I(1) against I(d) processes with d ∈ [0, 1). This is an important test in many economic applications because I(d) processess with d & 1 are mean-reverting although, when 0.5 ≤ d & 1,, like I(1) processes, they are nonstationary. We show how simple is the implementation of the FDF in these situations, and argue that it has better properties than LM tests. A simple testing strategy entailing only asymptotically normally distributed tests is also proposed. Finally, an empirical application is provided where the FDF test allowing for deterministic components is used to test for long-memory in the per capita GDP of several OECD countries, an issue that has important consequences to discriminate between growth theories, and on which there is some controversy.

Proyecto Delta : interrelación entre intérprete, obra y público en la música contemporánea

Proyecto Delta es una iniciativa escenográfica de un programa de concierto específico constituido con obras de música contemporánea. La propuesta se lleva a cabo gracias a un fundamento teórico que incluye reflexiones en torno a las figuras comprometidas en el acto musical escénico: intérprete, obra y público. En esta digresión sus funciones son objeto de un desfiguramiento, fomentando la capacidad creativa del intérprete como director artístico. El concierto se convierte, de este modo, en un producto acabado. En particular, el Proyecto Delta se construye sobre el diálogo entre lo sonoro y lo visual, lo audible y lo visible: la música y el espacio.

Cross-cultural adaptation of the Quality of Life Index Spinal Cord Injury - Version III

OBJECTIVE To translate and culturally adapt to Portuguese the Ferrans and Powers Quality of Life Index Spinal Cord Injury - Version III and characterize the sample in relation to sociodemographic and clinical aspects. METHOD A methodological study with view to cross-cultural adaptation, following the particular steps of this method: initial translation, translation synthesis, back-translation (translation back to the original language), review by a committee of judges and pretest of the final version. The pretest was carried out with 30 patients with spinal cord injury. RESULTS An index of 74 items divided into two parts (satisfaction/importance) was obtained. The criteria of semantic equivalence were evaluated as very adequate translation, higher than 87%, and vocabulary and were grammar higher than 86%. Idiomatic equivalence was higher than 74%, experimental greater than 78% and conceptual was greater than 70%. CONCLUSION After cross-cultural adaptation, the instrument proved semantic, idiomatic, experimental and conceptual adequacy, in addition to helping the evaluation of the quality of life of people with spinal cord injury.

Elevada prevalença de comorbilitats cardiovasculars en pacients amb artrosi de genolls i mans

Estudis epidemiològics han demostrat una relació entre l’artrosi i els factors de risc cardiovascular clàssics. Es tracta d’un estudi transversal amb 184 pacients amb artrosi de genoll, 70 amb artrosi de mans i 254 controls. Es recullen els diagnòstics de hipertensió arterial, diabetis mellitus, obesitat i dislipèmia i els episodis cardiovasculars. Observem una elevada prevalença de factors de risc cardiovasculars i agrupació d’aquests, resultant ambdues artrosi, un factor de risc indepedent per tal agrupació; i el que seria més important, els episodis cardiovasculars també resulten més freqüents en els dos grups d’artrosi.

Caution, children crossing: Heterogeneity of victim's cost of care and negligence rule

The paper deals with a bilateral accident situation in which victims haveheterogeneous costs of care. With perfect information,efficient care bythe injurer raises with the victim's cost. When the injurer cannot observeat all the victim's type, and this fact can be verified by Courts, first-bestcannot be implemented with the use of a negligence rule based on thefirst-best levels of care. Second-best leads the injurer to intermediate care,and the two types of victims to choose the best response to it. This second-bestsolution can be easily implemented by a negligence rule with second-best as duecare. We explore imperfect observation of the victim's type, characterizing theoptimal solution and examining the different legal alternatives when Courts cannotverify the injurers' statements. Counterintuitively, we show that there is nodifference at all between the use by Courts of a rule of complete trust and arule of complete distrust towards the injurers' statements. We then relate thefindings of the model to existing rules and doctrines in Common Law and Civil Lawlegal systems.

Regulation and opportunism: How much activism do we need?

This paper analyzes the current trend towards firms self-regulation as opposed to the formal regulation of a negative externality. Firms respond to increasing activism in the market(conscious consumers that take into account the external effects of their purchase) by providing more socially responsible goods. However, because regulation is the outcome of a political process, an increase in activism might imply an inefficiently higher externality level. This may happen when a majority of non-activist consumers collectively free-ride on conscious consumers. By determining a softer than optimal regulation, they benefit from the behavior of firms, yet they have access to cheaper (although less efficient) goods.

Optimal negligence rule under limited liability

We study the standard economic model of unilateral accidents, in its simplest form, assumingthat the injurers have limited assets.We identify a second-best optimal rule that selects as duecare the minimum of first-best care, and a level of care that takes into account the wealth ofthe injurer. We show that such a rule in fact maximizes the precautionary effort by a potentialinjurer. The idea is counterintuitive: Being softer on an injurer, in terms of the required level ofcare, actually improves the incentives to take care when he is potentially insolvent. We extendthe basic result to an entire population of potentially insolvent injurers, and find that the optimalgeneral standards of care do depend on wealth, and distribution of income. We also show theconditions for the result that higher income levels in a given society call for higher levels of carefor accidents.

Ignorance promotes competition: An auction model with endogenous private valuations

We study a situation in which an auctioneer wishes to sell an object toone of N risk-neutral bidders with heterogeneous preferences. Theauctioneer does not know bidders preferences but has private informationabout the characteristics of the ob ject, and must decide how muchinformation to reveal prior to the auction. We show that the auctioneerhas incentives to release less information than would be efficient andthat the amount of information released increases with the level ofcompetition (as measured by the number of bidders). Furthermore, in aperfectly competitive market the auctioneer would provide the efficientlevel of information.

Competition and cost overruns in procurement

Most cases of cost overruns in public procurement are related to important changes in theinitial project design. This paper deals with the problem of design speciffication in public procurement and provides a rationale for design misspeciffication. We propose a model in which the sponsor decides how much to invest in design speciffication and awards competitively the project to a contractor. After the project has been awarded the sponsor engages in bilateral renegotiation with the contractor, in order to accommodate changes in the initial project's design that new information makes desirable. When procurement takes place in the presence of horizontally differentiated contractors, the design's speciffication level is seen to affect the resulting degree of competition. The paper highlights this interaction between market competition and design speciffication and shows that the sponsor's optimal strategy, when facing an imperfectly competitive market supply, is to underinvest in design speciffication so as to make signifficant cost overrunslikely. Since no such misspeciffication occurs in a perfectly competitive market, cost overruns are seen to arise as a consequence of lack of competition in the procurement market.

Combating corruption in international business transactions

We analyze the impact of different types of international conventions thatrequire signatory countries to penalize domestic firms that are found tohave bribed foreign public officials. We analyze enforcement of penaltiesunder a convention styled after the OECD's 'Convention on Combating Briberyof Foreign Public Officials in International Business Transactions', in whichsignatory countries commit to prosecuting firms that have bribed publicofficials of any foreign country. We compare the results with the case inwhich the convention requires signatory countries to commit to prosecutingfirms that have bribed public officials of signatory countries only.We argue that the second type of convention is more likely to ensureenforcement of penalties on firms found to have bribed foreign publicofficials.

On information and competition in private value auctions

How much information does an auctioneer want bidders to have in a private value environment?We address this question using a novel approach to ordering information structures based on the property that in private value settings more information leads to a more disperse distribution of buyers updated expected valuations. We define the class of precision criteria following this approach and different notions of dispersion, and relate them to existing criteria of informativeness. Using supermodular precision, we obtain three results: (1) a more precise information structure yields a more efficient allocation; (2) the auctioneer provides less than the efficient level of information since more information increases bidder informational rents; (3) there is a strategic complementarity between information and competition, so that both the socially efficient and the auctioneer s optimal choice of precision increase with the number of bidders, and both converge as the number of bidders goes to infinity.

R&D in the pharmaceutical industry: A world of small innovations

It is commonly argued that in recent years pharmaceutical companies have directed theirR&D towards small improvements of existing compounds instead of more risky drastic innovations. In this paper we show that the proliferation of these small innovations is likely to be linked to the lack of market sensitivity of a part of the demand to changes in prices. Compared to their social contribution, small innovations are relatively more profitable than large ones because they are targeted to the smaller but more inelastic part of the demand. We also study the effect of regulatory instruments such as price ceilings, copayments and reference prices and extend the analysis to competition in research.

Responsabilidad social corporativa. Una visión desde la teoría económica

El objetivo de este trabajo es discutir y analizar el concepto de la responsabilidad socialcorporativa (RSC) desde la teoria económica. Para ello usamos un modelo sencilloque nos permite clarificar algunos aspectos del debate que rodea la RSC. Observamoscomo la motivación subyacente en las decisiones y estrategias empresariales juega unpapel importante en el concepto de RSC; así, aquellas políticas de la empresa quefavorecen a alguno de los stakeholders, pero estén simplemente destinadas a incrementarla rentabilidad empresarial, no deberían catalogarse como RSC. Otro aspectoclave de la RSC es su relación e interacción con la intervención y regulación pública.Desde nuestro punto de vista, el papel de la RSC será importante allí donde la regulación pública no puede llegar debido a, por ejemplo, restricciones de información alas que se enfrenta el sector público. Analizamos también el papel y las característicasdel activismo desarrollado por algunos grupos de consumidores (mediante el posiblelanzamiento de boicots a las empresas no responsables socialmente). Y, finalmente,nos planteamos la posibilidad de implementar la empresa stakeholder , es decir, laempresa Socialmente Responsable; la conclusión principal en este aspecto es que suimplementación se enfrenta a complejos problemas, especialmente en lo que concierneal diseño de los incentivos adecuados para los gestores de estas empresas.

Bases de dades relacionals

Aquest projecte neix de la necessitat de donar una solució a l'associació mundial de jugadors de bàsquet. Se'ns ha demanat crear una nova base de dades on tota la informació dels jugadors de bàsquet i el seu entorn quedin centralitzades.

Aplicación de integración entre ArcGIS y CartoDB

Memoria del desarrollo de una aplicación de integración entre ArcGIS y CartoDB.