Econometrics and decision making: Effects of presentation mode

Much of empirical economics involves regression analysis. However, does thepresentation of results affect economists ability to make inferences for decision makingpurposes? In a survey, 257 academic economists were asked to make probabilisticinferences on the basis of the outputs of a regression analysis presented in a standardformat. Questions concerned the distribution of the dependent variable conditional onknown values of the independent variable. However, many respondents underestimateduncertainty by failing to take into account the standard deviation of the estimatedresiduals. The addition of graphs did not substantially improve inferences. On the otherhand, when only graphs were provided (i.e., with no statistics), respondents weresubstantially more accurate. We discuss implications for improving practice in reportingresults of regression analyses.

The impact of gender composition on team performance and decision-making: Evidence from the field

We investigate whether the gender composition of teams affect theireconomic performance. We study a large business game, played in groups ofthree, where each group takes the role of a general manager. There are twoparallel competitions, one involving undergraduates and the other involvingMBAs. Our analysis shows that teams formed by three women aresignificantly outperformed by any other gender combination, both at theundergraduate and MBA levels. Looking across the performancedistribution, we find that for undergraduates, three women teams areoutperformed throughout, but by as much as 10pp at the bottom and by only1pp at the top. For MBAs, at the top, the best performing group is two menand one woman. The differences in performance are explained bydifferences in decision-making. We observe that three women teams are lessaggressive in their pricing strategies, invest less in R&D, and invest more insocial sustainability initiatives, than any other gender combination teams.Finally, we find support for the hypothesis that it is poor work dynamicsamong the three women teams that drives the results.

Giffen goods and market making

This paper shows that information effects per se are not responsible forthe Giffen goods anomaly affecting competitive traders demands in multi-asset, noisy rational expectations equilibrium models. The role thatinformation plays in traders strategies also matters. In a market withrisk averse, uninformed traders, informed agents havea dual motive for trading: speculation and market making. Whilespeculation entails using prices to assess the effect of private signalerror terms, market making requires employing them to disentangle noisetraders effects in traders aggregate orders. In a correlated environment,this complicates a trader s signal-extraction problem and maygenerate upward-sloping demand curves. Assuming either (i) that competitive,risk neutral market makers price the assets, or that (ii) the risktolerance coefficient of uninformed traders grows without bound, removesthe market making component from informed traders demands, rendering themwell behaved in prices.

The Impact of democratization: a preliminary investigation on social policies and political violence in Latin America

The recent strides of democracy in Latin America have been associated to conflicting outcomes. The expectation that democracy would bring about peace and prosperity have been only partly satisfied. While political violence has been by and large eradicated from the sub-continent, poverty and social injustice still prevail and hold sway. Our study argues that democracy matters for inequality through the growing strength of center left and left parties and by making political leaders in general more responsive to the underprivileged. Furthermore, although the pension reforms recently enacted in the region generated overall regressive outcomes on income distribution, democratic countries still benefit from their political past: where democratic tradition was stronger, such outcomes have been milder. Democratic tradition and the specific ideological connotations of the parties in power, on the other hand, did not play an equally crucial role in securing lower levels of political violence: during the last wave of democratizations in Latin America, domestic peace was rather an outcome of political and social concessions to those in distress. In sum, together with other factors and especially economic ones, the reason why recent democratizations have provided domestic peace in most cases, but have been unable so far to solve the problem of poverty and inequality, is that democratic traditions in the subcontinent have been relatively weak and, more specifically, that this weakness has undermined the growth of left and progressive parties, acting as an obstacle to redistribution. Such weakness, on the other hand, has not prevented the drastic reduction of domestic political violence, since what mattered in this case was a combination of symbolic or material concessions and political agreements among powerful élites and counter-élites.

Skill, Luck, Overconfidence, and Risk Taking

In most naturally occurring situations, success depends on both skill and chance. We compare experimental market entry decisions where payoffs depend on skill alone and combinations of skill and luck. We find more risk taking with skill and luck as opposed to skill alone, particularly for males, and little overconfidence. Our data support an explanation based on differential attitudes toward luck by those whose self-assessed skills are low and high. Making luck more important induces greater optimism for the former, while the latter maintain a belief that high levels of skill are sufficient to overcome the vagaries of chance.

A model of market-making

The two essential features of a decentralized economy taken intoaccount are, first, that individual agents need some informationabout other agents in order to meet potential trading partners,which requires some communication or interaction between theseagents, and second, that in general agents will face tradinguncertainty. We consider trade in a homogeneous commodity. Firmsdecide upon their effective supplies, and may create their ownmarkets by sending information signals communicating theirwillingness to sell. Meeting of potential trading partners isarranged in the form of shopping by consumers. The questions to beconsidered are: How do firms compete in such markets? And what arethe properties of an equilibrium? We establish existenceconditions for a symmetric Nash equilibrium in the firms'strategies, and analyze its characteristics. The developedframework appears to lend itself well to study many typicalphenomena of decentralized economies, such as the emergence ofcentral markets, the role of middlemen, and price-making.

On heuristic and linear models of judgment: Mapping the demand for knowledge

Research on judgment and decision making presents a confusing picture of human abilities. For example, much research has emphasized the dysfunctional aspects of judgmental heuristics, and yet, other findings suggest that these can be highly effective. A further line of research has modeled judgment as resulting from as if linear models. This paper illuminates the distinctions in these approaches by providing a common analytical framework based on the central theoretical premise that understanding human performance requires specifying how characteristics of the decision rules people use interact with the demands of the tasks they face. Our work synthesizes the analytical tools of lens model research with novel methodology developed to specify the effectiveness of heuristics in different environments and allows direct comparisons between the different approaches. We illustrate with both theoretical analyses and simulations. We further link our results to the empirical literature by a meta-analysis of lens model studies and estimate both human andheuristic performance in the same tasks. Our results highlight the trade-off betweenlinear models and heuristics. Whereas the former are cognitively demanding, the latterare simple to use. However, they require knowledge and thus maps of when andwhich heuristic to employ.

RiskDiff: A web tool for the analysis of the difference due to risk and demographic factors for incidence or mortality data.

Background Analysing the observed differences for incidence or mortality of a particular disease between two different situations (such as time points, geographical areas, gender or other social characteristics) can be useful both for scientific or administrative purposes. From an epidemiological and public health point of view, it is of great interest to assess the effect of demographic factors in these observed differences in order to elucidate the effect of the risk of developing a disease or dying from it. The method proposed by Bashir and Estève, which splits the observed variation into three components: risk, population structure and population size is a common choice at practice. Results A web-based application, called RiskDiff has been implemented (available at http://rht.iconcologia.net/riskdiff.htm webcite), to perform this kind of statistical analyses, providing text and graphical summaries. Code from the implemented functions in R is also provided. An application to cancer mortality data from Catalonia is used for illustration. Conclusions Combining epidemiological with demographical factors is crucial for analysing incidence or mortality from a disease, especially if the population pyramids show substantial differences. The tool implemented may serve to promote and divulgate the use of this method to give advice for epidemiologic interpretation and decision making in public health.

Déficits y sesgos neurocognitivos y afectivos en la toma de decisiones de jugadores patológios y otros trastornos

Los déficits y sesgos tanto cognitivos como afectivos han sido fuente creciente de interés en el ámbito de la Neurociéncia de los Trastornos Mentales. En este proyecto, que se inicia en 2004 y finaliza a finales de 2008, se han estudiado los siguientes Trastornos Mentales: Juego Patológico (JP), Trastornos de la Conducta Alimentaria (TCA) y Trastornos Depresivos. En esta memoria nos centraremos en resumir parte de los resultados obtenidos en un estudio sobre JP y toma de decisiones (articulo en revisión y pendiente de aceptación) y otro de funcionamiento ejecutivo en JP y Bulimia Nerviosa (BN) (artículo en prensa). Resumiento el primer estudio los JP (N=32) muestran un proceso de toma de decisiones sesgado por la búsqueda de recompensa en forma de elevada toma de riesgos en comparación con Controles Sanos (CS). También se observan déficits en flexibilidad cognitiva pero no en control inhibitorio entre JP y CS. Los resultados descartan miopía conductual para lo toma de decisiones en JP, pero apuntan a un sesgo cognitivo-afectivo, en el que el control de los impulsos jugaría un papel relevante, en forma de ilusión de control, para los procesos de toma de decisiones con recompensa inmediata pero con castigo diferido, medidos por una prueba de toma de decisiones (IGT ABCD). En el segundo estudio, basándose en las vulnerabilidadades compartidas descritas entre JP y BN se comparó el funcionamiento ejecutivo de mujeres con JP y BN. Tras la administración del WCST y Stroop y ajustando el análisis por edad y educación, las JP mostraron mayor afectación, en concreto mayor porcentaje de errores perservaritvos, menor nivel de respuestas conceptuales y mayor número de ensayos administrados, mientras que el grupo de BN mostró mayor porcentaje de errores no persevarativos. Ambas, mujeres JP y BN mostraron disfunción ejecutiva en relación a los CS pero con diferentes correlatos específcos.

Una explicación del conflicto social sobre energía eólica en la comarca de la Terra Alta en Cataluña

El estudio investiga las razones que explican un conflicto sobre la instalación de parques eólicos en Terra Alta, una comarca rural de Cataluña. Identificamos tres razones principales. Primero, y de acuerdo con el marco conceptual de ecología política, el conflicto eólico forma parte de un conflicto más generalizado sobre la ‘macro-concentración’ de instalaciones energéticas en el sur de Cataluña que generan energía y beneficios económicos principalmente para el centro del desarrollo económico catalán. Segundo, el impacto paisajístico de los proyectos eólicos choca con iniciativas locales que impulsan el paisaje como un activo valioso capaz de sustentar la vida en la comarca. Por último, desequilibrios de poder en el sistema formal de toma de decisiones sobre parques eólicos impiden la inclusión de valores locales como criterios en el proceso de toma de decisiones y eso también genera conflicto. Para un desarrollo sostenible de energía eólica, la importancia del potencial eólico como criterio principal de localización debe ser reevaluada, y la negociación de la distribución de beneficios debe hacerse en la forma más abierta posible.

Concepció, disseny i implantació d'un sistema de proves psicomètriques de rendiment acadèmic per a la matèria d'Història de la Música

Amb aquest projecte s'ha treballat en la direcció de: 1) Implementar un nou recurs en un projecte global de millora de la qualitat docent i d’aplicació de les TIC a l’ensenyament de les diferents assignatures de la matèria d’Història de la Música a la UdL en curs des de fa alguns anys. Concretament, diverses eines per a l’autoavaluació de l’alumnat a través d’un banc de preguntes segons el format de les proves psicomètriques (proves objectives en l’avaluació del rendiment acadèmic dels estudiants o d’elecció múltiple). 2) Arribar a disposar d’un extens banc de preguntes d’elecció múltiple i correcció objectiva en diferents formats, ordenades per blocs, temes, nivells de dificultat, etc., que reuneixin els criteris mínims de fiabilitat, objectivitat i validesa necessaris per a una correcta avaluació del rendiment acadèmic. Entenem que l’avaluació ha de tenir utilitats diferents que van més enllà de la simple puntuació de l’alumnat. Ha de servir també per millorar la docència, per facilitar l’aprenentatge de l’alumne, per assegurar un nivell de competència mínim, per discriminar entre estudiants o per informar la pròpia institució. 3) Aconseguir que l’alumne, a través de l’autoavaluació, entengui que aquest tipus de proves són instruments per continuar aprenent. En aquest sentit les proves d’elecció múltiple permeten tot un seguit d’opcions que ho afavoreixen. 4) Elaborar una eina amb capacitat de generar estadístiques, índex de discriminació i de fer l’anàlisi d’items, tot permetent anar redefinint i millorant els ítems.

Xarxes tolerants a endarreriments i interrupcions: desenvolupament d'un scheduler d'agents mòbils

En aquest projecte es proposa i s’implementa una nova forma de crear xarxes DTN (Delay-Tolerant Networks) mitjançant agents mòbils. Aquestes xarxes tenen la peculiaritat de ser tolerants a endarreriments i interrupcions, podent ser utilitzades en entorns on les xarxes actuals no es poden aplicar. Hem dissenyat mecanismes que permeten prendre decisions d’encaminament a nivell d’aplicació i mecanismes de priorització d’agents mitjançant informació d’alt nivell. Aquests mecanismes milloren les DTN fent-les més flexibles i efectives.

Viabilitat tècnica i econòmica de la implantació del mètode Ganimede® en un procés de vinificació

L’objecte del projecte és realitzar un estudi de viabilitat tècnica i econòmica respecte laimplantació del mètode Ganimede® en el procés de vinificació enfront els sistemesconvencionals. Aquest mètode es basa en la instal•lació dels dipòsits fermentadors patentats anomenats també Ganimede® que van néixer durant la verema 1997 de la mà de l’enòleg i inventor italià Francesco Marin

Analisi comparata delle produzioni vitivinicole : un confronto Emilia Romagna-Catalogna

In questo elaborato finale verrà affrontato uno studio comparato dei vini dell'Emilia Romagna e della Catalogna. La tesi spazierà dall'ottenimento del vino fino ai tempi attuali. Prima perciò, si parlerà delle origini del vino fino all'attualità, della situazione mondiale del vino, così in produzione come in coltivazione, consumo, etc. Dopo si concentrarà nell'Europa, dove si analizzeranno i diversi paesi produttori, passando dopo alla produzione italiana e spagnola e infine alle regioni dell'Emilia Romagna (Italia) e della Catalogna (Spagna) dove ci sarà un analisi più dettagliata in tutti gli aspetti