Tonic activity level in the right prefrontal cortex predicts individuals' risk taking

Human risk taking is characterized by a large amount of individual heterogeneity. In this study, we applied resting-state electroencephalography, which captures stable individual differences in neural activity, before subjects performed a risk-taking task. Using a source-localization technique, we found that the baseline cortical activity in the right prefrontal cortex predicts individual risk-taking behavior. Individuals with higher baseline cortical activity in this brain area display more risk aversion than do other individuals. This finding demonstrates that neural characteristics that are stable over time can predict a highly complex behavior such as risk-taking behavior and furthermore suggests that hypoactivity in the right prefrontal cortex might serve as a dispositional indicator of lower regulatory abilities, which is expressed in greater risk-taking behavior.

An investigation into the factors that encourage learner participation in a large group medical classroom

BACKGROUND: Effective lectures often incorporate activities that encourage learner participation. A challenge for educators is how to facilitate this in the large group lecture setting. This study investigates the individual student characteristics involved in encouraging (or dissuading) learners to interact, ask questions, and make comments in class. METHODS: Students enrolled in a Doctor of Veterinary Medicine program at Ross University School of Veterinary Medicine, St Kitts, were invited to complete a questionnaire canvassing their participation in the large group classroom. Data from the questionnaire were analyzed using Excel (Microsoft, Redmond, WA, USA) and the R software environment (http://www.r-project.org/). RESULTS: One hundred and ninety-two students completed the questionnaire (response rate, 85.7%). The results showed statistically significant differences between male and female students when asked to self-report their level of participation (P=0.011) and their confidence to participate (P<0.001) in class. No statistically significant difference was identified between different age groups of students (P=0.594). Student responses reflected that an "aversion to public speaking" acted as the main deterrent to participating during a lecture. Female participants were 3.56 times more likely to report a fear of public speaking than male participants (odds ratio 3.56, 95% confidence interval 1.28-12.33, P=0.01). Students also reported "smaller sizes of class and small group activities" and "other students participating" as factors that made it easier for them to participate during a lecture. CONCLUSION: In this study, sex likely played a role in learner participation in the large group veterinary classroom. Male students were more likely to participate in class and reported feeling more confident to participate than female students. Female students in this study commonly identified aversion to public speaking as a factor which held them back from participating in the large group lecture setting. These are important findings for veterinary and medical educators aiming to improve learner participation in the classroom. Potential ways of addressing this challenge include addition of small group activities and audience response systems during lectures, and inclusion of training interventions in public speaking at an early stage of veterinary and medical curricula.

Bargaining for power and information : an experimental and theoretical analysis of the interaction between institutions, externalities and adverse selection

Bargaining is the building block of many economic interactions, ranging from bilateral to multilateral encounters and from situations in which the actors are individuals to negotiations between firms or countries. In all these settings, economists have been intrigued for a long time by the fact that some projects, trades or agreements are not realized even though they are mutually beneficial. On the one hand, this has been explained by incomplete information. A firm may not be willing to offer a wage that is acceptable to a qualified worker, because it knows that there are also unqualified workers and cannot distinguish between the two types. This phenomenon is known as adverse selection. On the other hand, it has been argued that even with complete information, the presence of externalities may impede efficient outcomes. To see this, consider the example of climate change. If a subset of countries agrees to curb emissions, non-participant regions benefit from the signatories’ efforts without incurring costs. These free riding opportunities give rise to incentives to strategically improve ones bargaining power that work against the formation of a global agreement. This thesis is concerned with extending our understanding of both factors, adverse selection and externalities. The findings are based on empirical evidence from original laboratory experiments as well as game theoretic modeling. On a very general note, it is demonstrated that the institutions through which agents interact matter to a large extent. Insights are provided about which institutions we should expect to perform better than others, at least in terms of aggregate welfare. Chapters 1 and 2 focus on the problem of adverse selection. Effective operation of markets and other institutions often depends on good information transmission properties. In terms of the example introduced above, a firm is only willing to offer high wages if it receives enough positive signals about the worker’s quality during the application and wage bargaining process. In Chapter 1, it will be shown that repeated interaction coupled with time costs facilitates information transmission. By making the wage bargaining process costly for the worker, the firm is able to obtain more accurate information about the worker’s type. The cost could be pure time cost from delaying agreement or cost of effort arising from a multi-step interviewing process. In Chapter 2, I abstract from time cost and show that communication can play a similar role. The simple fact that a worker states to be of high quality may be informative. In Chapter 3, the focus is on a different source of inefficiency. Agents strive for bargaining power and thus may be motivated by incentives that are at odds with the socially efficient outcome. I have already mentioned the example of climate change. Other examples are coalitions within committees that are formed to secure voting power to block outcomes or groups that commit to different technological standards although a single standard would be optimal (e.g. the format war between HD and BlueRay). It will be shown that such inefficiencies are directly linked to the presence of externalities and a certain degree of irreversibility in actions. I now discuss the three articles in more detail. In Chapter 1, Olivier Bochet and I study a simple bilateral bargaining institution that eliminates trade failures arising from incomplete information. In this setting, a buyer makes offers to a seller in order to acquire a good. Whenever an offer is rejected by the seller, the buyer may submit a further offer. Bargaining is costly, because both parties suffer a (small) time cost after any rejection. The difficulties arise, because the good can be of low or high quality and the quality of the good is only known to the seller. Indeed, without the possibility to make repeated offers, it is too risky for the buyer to offer prices that allow for trade of high quality goods. When allowing for repeated offers, however, at equilibrium both types of goods trade with probability one. We provide an experimental test of these predictions. Buyers gather information about sellers using specific price offers and rates of trade are high, much as the model’s qualitative predictions. We also observe a persistent over-delay before trade occurs, and this mitigates efficiency substantially. Possible channels for over-delay are identified in the form of two behavioral assumptions missing from the standard model, loss aversion (buyers) and haggling (sellers), which reconcile the data with the theoretical predictions. Chapter 2 also studies adverse selection, but interaction between buyers and sellers now takes place within a market rather than isolated pairs. Remarkably, in a market it suffices to let agents communicate in a very simple manner to mitigate trade failures. The key insight is that better informed agents (sellers) are willing to truthfully reveal their private information, because by doing so they are able to reduce search frictions and attract more buyers. Behavior observed in the experimental sessions closely follows the theoretical predictions. As a consequence, costless and non-binding communication (cheap talk) significantly raises rates of trade and welfare. Previous experiments have documented that cheap talk alleviates inefficiencies due to asymmetric information. These findings are explained by pro-social preferences and lie aversion. I use appropriate control treatments to show that such consideration play only a minor role in our market. Instead, the experiment highlights the ability to organize markets as a new channel through which communication can facilitate trade in the presence of private information. In Chapter 3, I theoretically explore coalition formation via multilateral bargaining under complete information. The environment studied is extremely rich in the sense that the model allows for all kinds of externalities. This is achieved by using so-called partition functions, which pin down a coalitional worth for each possible coalition in each possible coalition structure. It is found that although binding agreements can be written, efficiency is not guaranteed, because the negotiation process is inherently non-cooperative. The prospects of cooperation are shown to crucially depend on i) the degree to which players can renegotiate and gradually build up agreements and ii) the absence of a certain type of externalities that can loosely be described as incentives to free ride. Moreover, the willingness to concede bargaining power is identified as a novel reason for gradualism. Another key contribution of the study is that it identifies a strong connection between the Core, one of the most important concepts in cooperative game theory, and the set of environments for which efficiency is attained even without renegotiation.

Notas para una arqueología de los temores infantiles : El Río de La Plata en el siglo XIX

Los adultos, muy poco dispuestos a poner en evidencia sus debilidades, se muestran reacios a reconocer sus temores. Los niños y niñas desconociendo en gran medida, convenciones y prácticas sociales restrictivas de lo emocional, se han mostrado y se muestran más libres en aceptar y hablar de sus miedos. Este miedo, ya en sus experiencias individuales o colectivas, puede definirse como la aversión a alguien o alguna cosa, que provoca, invariablemente, incapacidades, restricciones de la acción en distinto grado. Nos hemos propuesto advertir este miedo infantil, no sólo con el objeto de individualizar sus causas y efectos, sino también confirmar su persistencia a lo largo de los años, así como advertir como estos condicionaron la existencia infantil de generaciones posteriores.

La estigmatización de los mendigos en El Buscón : Similitudes con la persecución de otros grupos marginados

Los mendigos fueron estigmatizados durante la temprana modernidad, convirtiéndose en sujetos sospechosos sobre los cuales recaían múltiples acusaciones. En el presente trabajo veremos cómo La vida del Buscón llamado Don Pablos reproduce este discurso, en el cual encontramos varias similitudes con la marginación de otros grupos sociales en este mismo período de consolidación monárquica. A partir de esto, manejamos la hipótesis de que este texto es parte de la configuración de un enemigo interno que debía ser perseguido y respecto del cual era necesario generar, a través de la aversión y el temor generalizados, el rechazo de la población

Notas para una arqueología de los temores infantiles : El Río de La Plata en el siglo XIX

Los adultos, muy poco dispuestos a poner en evidencia sus debilidades, se muestran reacios a reconocer sus temores. Los niños y niñas desconociendo en gran medida, convenciones y prácticas sociales restrictivas de lo emocional, se han mostrado y se muestran más libres en aceptar y hablar de sus miedos. Este miedo, ya en sus experiencias individuales o colectivas, puede definirse como la aversión a alguien o alguna cosa, que provoca, invariablemente, incapacidades, restricciones de la acción en distinto grado. Nos hemos propuesto advertir este miedo infantil, no sólo con el objeto de individualizar sus causas y efectos, sino también confirmar su persistencia a lo largo de los años, así como advertir como estos condicionaron la existencia infantil de generaciones posteriores.

La estigmatización de los mendigos en El Buscón : Similitudes con la persecución de otros grupos marginados

Los mendigos fueron estigmatizados durante la temprana modernidad, convirtiéndose en sujetos sospechosos sobre los cuales recaían múltiples acusaciones. En el presente trabajo veremos cómo La vida del Buscón llamado Don Pablos reproduce este discurso, en el cual encontramos varias similitudes con la marginación de otros grupos sociales en este mismo período de consolidación monárquica. A partir de esto, manejamos la hipótesis de que este texto es parte de la configuración de un enemigo interno que debía ser perseguido y respecto del cual era necesario generar, a través de la aversión y el temor generalizados, el rechazo de la población

Notas para una arqueología de los temores infantiles : El Río de La Plata en el siglo XIX

Los adultos, muy poco dispuestos a poner en evidencia sus debilidades, se muestran reacios a reconocer sus temores. Los niños y niñas desconociendo en gran medida, convenciones y prácticas sociales restrictivas de lo emocional, se han mostrado y se muestran más libres en aceptar y hablar de sus miedos. Este miedo, ya en sus experiencias individuales o colectivas, puede definirse como la aversión a alguien o alguna cosa, que provoca, invariablemente, incapacidades, restricciones de la acción en distinto grado. Nos hemos propuesto advertir este miedo infantil, no sólo con el objeto de individualizar sus causas y efectos, sino también confirmar su persistencia a lo largo de los años, así como advertir como estos condicionaron la existencia infantil de generaciones posteriores.

La estigmatización de los mendigos en El Buscón : Similitudes con la persecución de otros grupos marginados

Los mendigos fueron estigmatizados durante la temprana modernidad, convirtiéndose en sujetos sospechosos sobre los cuales recaían múltiples acusaciones. En el presente trabajo veremos cómo La vida del Buscón llamado Don Pablos reproduce este discurso, en el cual encontramos varias similitudes con la marginación de otros grupos sociales en este mismo período de consolidación monárquica. A partir de esto, manejamos la hipótesis de que este texto es parte de la configuración de un enemigo interno que debía ser perseguido y respecto del cual era necesario generar, a través de la aversión y el temor generalizados, el rechazo de la población

Model experiment on optimal size of a fish stock with environmental uncertainties

We analyze the effect of environmental uncertainties on optimal fishery management in a bio-economic fishery model. Unlike most of the literature on resource economics, but in line with ecological models, we allow the different biological processes of survival and recruitment to be affected differently by environmental uncertainties. We show that the overall effect of uncertainty on the optimal size of a fish stock is ambiguous, depending on the prudence of the value function. For the case of a risk-neutral fishery manager, the overall effect depends on the relative magnitude of two opposing effects, the 'convex-cost effect' and the 'gambling effect'. We apply the analysis to the Baltic cod and the North Sea herring fisheries, concluding that for risk neutral agents the net effect of environmental uncertainties on the optimal size of these fish stocks is negative, albeit small in absolute value. Under risk aversion, the effect on optimal stock size is positive for sufficiently high coefficients of constant relative risk aversion.

Application of the agency theory for the analysis of performance-based mechanisms in road management

El WCTR es un congreso de reconocido prestigio internacional en el ámbito de la investigación del transporte, y aunque las actas publicadas están en formato digital y sin ISSN ni ISBN, lo consideramos lo suficientemente importante como para que se considere en los indicadores. This paper develops a model based on agency theory to analyze road management systems (under the different contract forms available today) that employ a mechanism of performance indicators to establish the payment of the agent. The base assumption is that of asymmetric information between the principal (Public Authorities) and the agent (contractor) and the risk aversion of this latter. It is assumed that the principal may only measure the agent?s performance indirectly and by means of certain performance indicators that may be verified by the authorities. In this model there is presumed to be a relation between the efforts made by the agent and the performance level measured by the corresponding indicators, though it is also considered that there may be dispersion between both variables that gives rise to a certain degree of randomness in the contract. An analysis of the optimal contract has been made on the basis of this model and in accordance with a series of parameters that characterize the economic environment and the particular conditions of road infrastructure. As a result of the analysis made, it is considered that an optimal contract should generally combine a fixed component and a payment in accordance with the performance level obtained. The higher the risk aversion of the agent and the greater the marginal cost of public funds, the lower the impact of this performance-based payment. By way of conclusion, the system of performance indicators should be as broad as possible but should not overweight those indicators that encompass greater randomness in their results.

Analysis of the Optimal Sharing of Construction Risk in Public Procurement Contracts

This paper discusses a model based on the agency theory to analyze the optimal transfer of construction risk in public works contracts. The base assumption is that of a contract between a principal (public authority) and an agent (firm), where the payment mechanism is linear and contains an incentive mechanism to enhance the effort of the agent to reduce construction costs. A theoretical model is proposed starting from a cost function with a random component and assuming that both the public authority and the firm are risk averse. The main outcome of the paper is that the optimal transfer of construction risk will be lower when the variance of errors in cost forecast, the risk aversion of the firm and the marginal cost of public funds are larger, while the optimal transfer of construction risk will grow when the variance of errors in cost monitoring and the risk aversion of the public authority are larger

A TEOLOGIA DA MISSÃO INTEGRAL:APROXIMAÇÕES E IMPEDIMENTOS ENTRE EVANGÉLICOS E EVANGELICAIS

A identidade do Movimento Evangélico vem dos puritanos, dos movimentos avivalistas, mas principalmente dos milenarismos que marcaram o final do século XIX e o começo do século XX. Os pressupostos do fundamentalismo foram articulados exatamente para dar sustentação ao anseio escatológico desses grupos. A identidade evangélica se formou a partir dos vexames do fundamentalismo que tentou diminuir o impacto do darwinismo nos Estados Unidos. Os evangélicos se organizaram e mostraram capacidade de mobilização. Seminários, revistas, conferências e eventos evangelísticos tornaram os evangélicos uma força no cenário mundial, principalmente na América Latina. Embora tenham demonstrado maior flexibilidade em interagir com a cultura, os evangélicos mantiveram os pressupostos milenaristas e fundamentalistas. Na América Latina, conseguiram relevante participação no Congresso Internacional de Evangelização em Lausanne, 1974. Foi proposto que a missão da igreja incluísse responsabilidade social com a mesma relevância que a proclamação dos conteúdos da fé. Mesmo tendo chegado tarde ao Brasil, lideranças jovens se mobilizaram em torno da proposta da Missão Integral. Entretanto, a questão sobre o que deve ser considerado prioritário não foi totalmente respondido, gerando decepção e desencorajamento entre evangelicais.(AU)

A TEOLOGIA DA MISSÃO INTEGRAL:APROXIMAÇÕES E IMPEDIMENTOS ENTRE EVANGÉLICOS E EVANGELICAIS

A identidade do Movimento Evangélico vem dos puritanos, dos movimentos avivalistas, mas principalmente dos milenarismos que marcaram o final do século XIX e o começo do século XX. Os pressupostos do fundamentalismo foram articulados exatamente para dar sustentação ao anseio escatológico desses grupos. A identidade evangélica se formou a partir dos vexames do fundamentalismo que tentou diminuir o impacto do darwinismo nos Estados Unidos. Os evangélicos se organizaram e mostraram capacidade de mobilização. Seminários, revistas, conferências e eventos evangelísticos tornaram os evangélicos uma força no cenário mundial, principalmente na América Latina. Embora tenham demonstrado maior flexibilidade em interagir com a cultura, os evangélicos mantiveram os pressupostos milenaristas e fundamentalistas. Na América Latina, conseguiram relevante participação no Congresso Internacional de Evangelização em Lausanne, 1974. Foi proposto que a missão da igreja incluísse responsabilidade social com a mesma relevância que a proclamação dos conteúdos da fé. Mesmo tendo chegado tarde ao Brasil, lideranças jovens se mobilizaram em torno da proposta da Missão Integral. Entretanto, a questão sobre o que deve ser considerado prioritário não foi totalmente respondido, gerando decepção e desencorajamento entre evangelicais.(AU)

UMA ANÁLISE DA RELAÇÃO ENTRE VARIÁVEIS MACROECONÔMICAS E O COMPORTAMENTO DAS AÇÕES DE MAIOR LIQUIDEZ DO ÍNDICE IBOVESPA

As ações de maior liquidez do índice IBOVESPA, refletem o comportamento das ações de um modo geral, bem como a relação das variáveis macroeconômicas em seu comportamento e estão entre as mais negociadas no mercado de capitais brasileiro. Desta forma, pode-se entender que há reflexos de fatores que impactam as empresas de maior liquidez que definem o comportamento das variáveis macroeconômicas e que o inverso também é uma verdade, oscilações nos fatores macroeconômicos também afetam as ações de maior liquidez, como IPCA, PIB, SELIC e Taxa de Câmbio. O estudo propõe uma análise da relação existente entre variáveis macroeconômicas e o comportamento das ações de maior liquidez do índice IBOVESPA, corroborando com estudos que buscam entender a influência de fatores macroeconômicos sobre o preço de ações e contribuindo empiricamente com a formação de portfólios de investimento. O trabalho abrangeu o período de 2008 a 2014. Os resultados concluíram que a formação de carteiras, visando a proteção do capital investido, deve conter ativos com correlação negativa em relação às variáveis estudadas, o que torna possível a composição de uma carteira com risco reduzido.