Fear state induced by diazepam withdrawal may be due to the sensitization of the neural substrates of aversion in the dPAG

This work was supported by FAPESP (P.N. 04/02859-0)

Experimental results for Myopic Loss Aversion

This data is experimental results of "Myopic Loss Aversion: An Experimental Analysis for the Flexibility of Investment and the Frequency of Information Feedback Using Two Period Binomial Stock Model".

Testing reference dependence, loss aversion and diminishing sensitivity in Spanish tourism

Based on Tversky and Kahneman’s Prospect Theory, we test the existence of reference dependence, loss aversion and diminishing sensitivity in Spanish tourism. To do this, we incorporate the reference-dependent model into a Multinomial Logit Model with Random Parameters -which controls for heterogeneity- and apply it to a sample of vacation choices made by Spaniards. We find that the difference between reference price and actual price is considered to make decisions, confirming that reference dependence exists; that people react more strongly to price increases than to price decreases relative to their reference price, which represents evidence in favor of the loss aversion phenomenon; and that there is diminishing sensitivity for losses only, showing convexity for these negative values.

Direct versus indirect channels: Differentiated loss aversion in a high‐involvement, non‐frequently purchased hedonic product

Purpose – This article aims to investigate whether intermediaries reduce loss aversion in the context of a high-involvement non-frequently purchased hedonic product (tourism packages). Design/methodology/approach – The study incorporates the reference-dependent model into a multinomial logit model with random parameters, which controls for heterogeneity and allows representation of different correlation patterns between non-independent alternatives. Findings – Differentiated loss aversion is found: consumers buying high-involvement non-frequently purchased hedonic products are less loss averse when using an intermediary than when dealing with each provider separately and booking their services independently. This result can be taken as identifying consumer-based added value provided by the intermediaries. Practical implications – Knowing the effect of an increase in their prices is crucial for tourism collective brands (e.g. “sun and sea”, “inland”, “green destinations”, “World Heritage destinations”). This is especially applicable nowadays on account of the fact that many destinations have lowered prices to attract tourists (although, in the future, they will have to put prices back up to their normal levels). The negative effect of raising prices can be absorbed more easily via indirect channels when compared to individual providers, as the influence of loss aversion is lower for the former than the latter. The key implication is that intermediaries can – and should – add value in competition with direct e-tailing. Originality/value – Research on loss aversion in retailing has been prolific, exclusively focused on low-involvement and frequently purchased products without distinguishing the direct or indirect character of the distribution channel. However, less is known about other types of products such as high-involvement non-frequently purchased hedonic products. This article focuses on the latter and analyzes different patterns of loss aversion in direct and indirect channels.

Jointly radial and translation homothetic preferences: generalized constant risk aversion

The paper identifies the structural restrictions on preferences required for them to exhibit both translation homotheticity in particular direction and radial homotheticity. The results are illustrated by an application to an asset allocation problem in the absence of riskless asset.

Supermodularity and risk aversion

In this paper, we consider the relationship between supermodularity and risk aversion. We show that supermodularity of the certainty equivalent implies that the certainty equivalent of any random variable is less than its mean. We also derive conditions under which supermodularity of the certainty equivalent is equivalent to aversion to mean-preserving spreads in the sense of Rothschild and Stiglitz. (c) 2006 Elsevier B.V. All rights reserved.

Age-related striatal BOLD changes without changes in behavioral loss aversion

Loss aversion (LA), the idea that negative valuations have a higher psychological impact than positive ones, is considered an important variable in consumer research. The literature on aging and behavior suggests older individuals may show more LA, although it is not clear if this is an effect of aging in general (as in the continuum from age 20 and 50 years), or of the state of older age (e.g., past age 65 years). We also have not yet identified the potential biological effects of aging on the neural processing of LA. In the current study we used a cohort of subjects with a 30 year range of ages, and performed whole brain functional MRI (fMRI) to examine the ventral striatum/nucleus accumbens (VS/NAc) response during a passive viewing of affective faces with model-based fMRI analysis incorporating behavioral data from a validated approach/avoidance task with the same stimuli. Our a priori focus on the VS/NAc was based on (1) the VS/NAc being a central region for reward/aversion processing; (2) its activation to both positive and negative stimuli; (3) its reported involvement with tracking LA. LA from approach/avoidance to affective faces showed excellent fidelity to published measures of LA. Imaging results were then compared to the behavioral measure of LA using the same affective faces. Although there was no relationship between age and LA, we observed increasing neural differential sensitivity (NDS) of the VS/NAc to avoidance responses (negative valuations) relative to approach responses (positive valuations) with increasing age. These findings suggest that a central region for reward/aversion processing changes with age, and may require more activation to produce the same LA behavior as in younger individuals, consistent with the idea of neural efficiency observed with high IQ individuals showing less brain activation to complete the same task.

Essays on risk aversion, diversification and non -participation

My dissertation consists of three essays. The central theme of these essays is the psychological factors and biases that affect the portfolio allocation decision. The first essay entitled, “Are women more risk-averse than men?” examines the gender difference in risk aversion as revealed by actual investment choices. Using a sample that controls for biases in the level of education and finance knowledge, there is evidence that when individuals have the same level of education, irrespective of their knowledge of finance, women are no more risk-averse than their male counterparts. However, the gender-risk aversion relation is also a function of age, income, wealth, marital status, race/ethnicity and the number of children in the household. The second essay entitled, “Can diversification be learned ?” investigates if investors who have superior investment knowledge are more likely to actively seek diversification benefits and are less prone to allocation biases. Results of cross-sectional analyses suggest that knowledge of finance increases the likelihood that an investor will efficiently allocate his direct investments across the major asset classes; invest in foreign assets; and hold a diversified equity portfolio. However, there is no evidence that investors who are more financially sophisticated make superior allocation decisions in their retirement savings. The final essay entitled, “The demographics of non-participation ”, examines the factors that affect the decision not to hold stocks. The results of probit regression models indicate that when individuals are highly educated, the decision to not participate in the stock market is less related to demographic factors. In particular, when individuals have attained at least a college degree and have advanced knowledge of finance, they are significantly more likely to invest in equities either directly or indirectly through mutual funds or their retirement savings. There is also evidence that the decision not to hold stocks is motivated by short-term market expectations and the most recent investment experience. The findings of these essays should increase the body of research that seeks to reconcile what investors actually do (positive theory) with what traditional theories of finance predict that investors should do (normative theory).

Essays on Risk Aversion, Diversification and Non-Participation

My dissertation consists of three essays. The central theme of these essays is the psychological factors and biases that affect the portfolio allocation decision. The first essay entitled, “Are women more risk-averse than men?” examines the gender difference in risk aversion as revealed by actual investment choices. Using a sample that controls for biases in the level of education and finance knowledge, there is evidence that when individuals have the same level of education, irrespective of their knowledge of finance, women are no more risk-averse than their male counterparts. However, the gender-risk aversion relation is also a function of age, income, wealth, marital status, race/ethnicity and the number of children in the household. The second essay entitled, “Can diversification be learned?” investigates if investors who have superior investment knowledge are more likely to actively seek diversification benefits and are less prone to allocation biases. Results of cross-sectional analyses suggest that knowledge of finance increases the likelihood that an investor will efficiently allocate his direct investments across the major asset classes; invest in foreign assets; and hold a diversified equity portfolio. However, there is no evidence that investors who are more financially sophisticated make superior allocation decisions in their retirement savings. The final essay entitled, “The demographics of non-participation”, examines the factors that affect the decision not to hold stocks. The results of probit regression models indicate that when individuals are highly educated, the decision to not participate in the stock market is less related to demographic factors. In particular, when individuals have attained at least a college degree and have advanced knowledge of finance, they are significantly more likely to invest in equities either directly or indirectly through mutual funds or their retirement savings. There is also evidence that the decision not to hold stocks is motivated by short-term market expectations and the most recent investment experience. The findings of these essays should increase the body of research that seeks to reconcile what investors actually do (positive theory) with what traditional theories of finance predict that investors should do (normative theory).

Can cognitive skills and risk aversion explain inconsistent choices?: an experiment

Estudia la coherencia de las preferencias de riesgo entre universitarios en un país en vías de desarrollo. El diseño permite obtener la coherencia a nivel individual, en el que cada sujeto selecciona sus opciones preferidas de dos diferentes, pero relacionadas tareas de obtención de riesgo. En la primera tarea, los sujetos eligen una opción entre seis alternativas, descartando así la inconsistencia. La segunda tarea, es una transformación de la primera, que está destinada a examinar si la elección en la primera tarea también se revela como preferida. Al usar estas opciones, se construye medidas de preferencias incoherentes y analiza su correlación con las habilidades cognitivas (medido según Frederick (2005) en Cognitive Reflection Test—CRT scores and students’ GPAs) y las preferencias de riesgo. Se encontró que una puntuación CRT baja y un pobre rendimiento académico son, generalmente buenos predictores de decisiones inconsistentes. Los resultados son contradictorios en términos del papel de la aversión al riesgo.

Joseph A. Schumpeter, capitalism, socialism, and democracy

This is a review of "Capitalism, socialism, and democracy", by Joseph A. Schumpeter, New York, Harper Perennial, 1942 (first Harper Colophon edition published 1975). "The public mind has by now so thoroughly grown out of humor with it as to make condemnation of capitalism and all its works a foregone conclusion – almost a requirement of the etiquette of discussion. Whatever his political preference, every writer or speaker hastens to conform to this code and to emphasize his critical attitude, his freedom from ‘complacency’, his belief in the inadequacies of capitalist achievement, his aversion to capitalist and his sympathy with anti-capitalist interests. Any other attitude is voted not only foolish but anti-social and is looked upon as an indication of immoral servitude." We might easily mistake this for a voice weary of contemplating the implications for neo-liberal nostrums of our current global financial crisis were it not for the rather formal, slightly arch, style and the gender exclusive language. It was in fact penned in the depths of World War II by Harvard economist Joseph Schumpeter, who fell off the map only to re-emerge from the 1970s as oil shocks and stagflation in the west presaged the decline of the Keynesian settlement, as east Asian newly industrialising economies were modelling on his insistence that entrepreneurialism, access to credit and trade were the pillars of economic growth, and as innovation became more of a watchword for post-industrial economies in general. The second coming was perhaps affirmed when his work was dubbed by Forbes in 1983 – on the occasion of the 100th anniversary of the birth of both men – as of greater explanatory import than Keynes’. (And what of our present resurgent Keynesian moment?)...

The impact of distributional preferences on (experimental) markets for expert services

Theory predicts that efficiency prevails on credence goods markets if customers are able to verify which quality they receive from an expert seller. In a series of experiments with endogenous prices we observe that verifiability fails to result in efficient provision behaviour and leads to very similar results as a setting without verifiability. Some sellers always provide appropriate treatment even if own money maximization calls for over- or undertreatment. Overall our endogenous-price-results suggests that both inequality aversion and a taste for efficiency play an important role for experts’ provision behaviour. We contrast the implications of those two motivations theoretically and discriminate between them empirically using a fixed-price design. We then classify experimental experts according to their provision behaviour.

Gender and public attitude toward corruption and tax evasion

The topics of corruption and tax evasion have attracted significant attention in the literature in recent years. We build on that literature by investigating empirically: (1) whether attitudes toward corruption and tax evasion vary systematically with gender and (2) whether gender differences decline as men and women face similar opportunities for illicit behavior. We use data on eight Western European countries from the World Values Survey and the European Values Survey. The results reveal significantly greater aversion to corruption and tax evasion among women. This holds across countries and time, and across numerous empirical specifications. (JEL H260, D730, J160, Z130)