Changes in liking for a no added salt soup as a function of exposure

Multiple exposures have been shown to increase preference for novel foods or flavours. This "mere exposure" effect is also well known anecdotally for changes in preference for tastants within foods, for example reducing sugar in tea or coffee. However, to date, this phenomenon has received little scientific attention. The present study addressed this issue in relation to changes in preference for salt within soup. Following an initial assessment of liking, familiarity and saltiness of six soups varying in salt content (0 - 337 mg NaCl/ml), thirty-seven participants, previously assessed for their preferred salt level in soup, were allocated to either an exposure group that received 20 ml soup samples with no added salt, to a group that received a 280 ml bowl of this soup, or to a control group that received 20 ml soup samples containing salt at 280mg/100g (within normal, commercial range). Soups were presented on eight occasions, at approximately daily intervals. The two groups receiving the no added salt soup showed increases in liking starting at the third exposure, and also evident in a repeat assessment following the exposures. Increases in familiarity of the no added salt soup were also evident during exposure. Rated saltiness of all soups increased as a function of exposure, so a change in saltiness perception could not account for changes in liking for just the no added salt soups. These data suggest that simple exposure to the taste of the no added salt soup was sufficient to increase liking to a level equivalent to the initially more preferred salt level.

Social networks and occupational choice: the endogenous formation of attitudes and beliefs about tax compliance

The paper analyses the emergence of group-specific attitudes and beliefs about tax compliance when individuals interact in a social network. It develops a model in which taxpayers possess a range of individual characteristics – including attitude to risk, potential for success in self-employment, and the weight attached to the social custom for honesty – and make an occupational choice based on these characteristics. Occupations differ in the possibility for evading tax. The social network determines which taxpayers are linked, and information about auditing and compliance is transmitted at meetings between linked taxpayers. Using agent-based simulations, the analysis demonstrates how attitudes and beliefs endogenously emerge that differ across sub-groups of the population. Compliance behaviour is different across occupational groups, and this is reinforced by the development of group-specific attitudes and beliefs. Taxpayers self-select into occupations according to the degree of risk aversion, the subjective probability of audit is sustained above the objective probability, and the weight attached to the social custom differs across occupations. These factors combine to lead to compliance levels that differ across occupations.

A theory of rational spatial agglomerations

We model the behavior of rational forward-looking agents in a spatial economy. The economic geography structure is built on Fujita et al. (1999)'s racetrack economy. Workers choose optimally what to consume at each period, as well as which spatial itinerary to follow in the geographical space. The spatial extent of the resulting agglomerations increases with the taste for variety and the expenditure share on manufactured goods, and decreases with transport costs. Because forward-looking agents anticipate the future formation of agglomerations, they are more responsive to spatial utility differentials than myopic agents. As a consequence, the emerging agglomerations are larger under perfect foresight spatial adjustments than under myopic ones.

Revenue-neutral tax policy under price uncertainty

The firm's response to revenue-neutral taxation is investigated under price uncertainty. Revenue-neutral policies adjust simultaneously the marginal tax rate and the level of exemptions while keeping expected tax receipts constant. Nonincreasing absolute risk aversion is sufficient to sign the firm's response: a reduction in the marginal rate causes the firm to contract output. Implications are established for the equilibrium level of treasury receipts.

Influence of sugar type on the bioavailability of cocoa flavanols.

The beneficial effects of cocoa on vascular function are mediated by the absorption of monomeric flavanols into the circulation from the small intestine. As such, an understanding of the impact of the food matrix on the delivery of flavanols to the circulation is critical in assessing the potential vascular impact of a food. In the present study, we investigated the impact of carbohydrate type on flavanol absorption and metabolism from chocolate. A randomised, double-blind, three-arm cross-over study was conducted, where fifteen volunteers were randomly assigned to either a high-flavanol (266 mg) chocolate containing maltitol, a high-flavanol (251 mg) chocolate with sucrose or a low-flavanol (48 mg) chocolate with sucrose. Test chocolates were matched for micro- and macronutrients, including the alkaloids theobromine and caffeine, and were similar in taste and appearance. Total flavanol absorption was lower after consumption of the maltitol-containing test chocolate compared with following consumption of its sucrose-containing equivalent (P = 0·002). Although the O-methylation pattern observed for absorbed flavanols was unaffected by sugar type, individual levels of unmethylated ( - )-epicatechin metabolites, 3'-O-methyl-epicatechin and 4'-O-methyl-epicatechin metabolites were lower for the maltitol-containing test chocolate compared with the sucrose-containing equivalent. Despite a reduction in the total plasma pool of flavanols, the maximum time (T max) was unaffected. The present data indicate that full assessment of intervention treatments is vital in future intervention trials with flavanols and that carbohydrate content is an important determinant for the optimal delivery of flavanols to the circulation.

Accounting for the economic risk, caused by variation in disease severity, in fungicide dose decisions: exemplified for Mycosphaerella graminicola on winter wheat

A method is presented to calculate economic optimum fungicide doses accounting for the risk-aversion of growers responding to variability in disease severity between crops. Simple dose-response and disease-yield loss functions are used to estimate net disease-related costs (fungicide cost, plus disease-induced yield loss) as a function of dose and untreated severity. With fairly general assumptions about the shapes of the probability distribution of disease severity and the other functions involved, we show that a choice of fungicide dose which minimises net costs on average across seasons results in occasional large net costs caused by inadequate control in high disease seasons. This may be unacceptable to a grower with limited capital. A risk-averse grower can choose to reduce the size and frequency of such losses by applying a higher dose as insurance. For example, a grower may decide to accept ‘high loss’ years one year in ten or one year in twenty (i.e. specifying a proportion of years in which disease severity and net costs will be above a specified level). Our analysis shows that taking into account disease severity variation and risk-aversion will usually increase the dose applied by an economically rational grower. The analysis is illustrated with data on septoria tritici leaf blotch of wheat caused by Mycosphaerella graminicola. Observations from untreated field plots at sites across England over three years were used to estimate the probability distribution of disease severities at mid-grain filling. In the absence of a fully reliable disease forecasting scheme, reducing the frequency of ‘high loss’ years requires substantially higher doses to be applied to all crops. Disease resistant cultivars reduce both the optimal dose at all levels of risk and the disease-related costs at all doses.

Housing densities and consumer choice

From 2001, the construction of flats and high-density developments increased in England and the building of houses declined. Does this indicate a change in taste or is it a result of government planning policies? In this paper, an analysis is made of the long-term effects of the policy of constraint which has existed for the past 50 years but the increase in density is identified as occurring primarily after new, revised, planning guidance was issued in England in 2000 which discouraged low-density development. To substantiate this, it is pointed out that the change which occurred in England did not occur in Scotland where guidance was not changed to encourage high-density residential development. The conclusion that the change is the result of planning policies and not of a change in taste is confirmed by surveys of the occupants of new high-rise developments in Leeds. The new flat-dwellers were predominantly young and childless and expressed the intention, in the near future, when they could, of moving out of the city centre and into houses. From recent changes in guidance by the new coalition government, it is expected that the construction of flats in England will fall back to earlier levels over the next few years.

Evidence on caste based discrimination

Caste based quotas in hiring have existed in the public sector in India for decades. Recently there has been debate about introducing similar quotas in private sector jobs. This paper uses a correspondence study to determine the extent of caste based discrimination in the Indian private sector. On average low-caste applicants need to send 20% more resumes than high-caste applicants to get the same callback. Differences in callback which favor high-caste applicants are particularly large when hiring is done by male recruiters or by Hindu recruiters. This finding provides evidence that differences in callback between high and low-caste applicants are not entirely due to statistical discrimination. High-caste applicants are also differentially favored by firms with a smaller scale of operations, while low-caste applicants are favored by firms with a larger scale of operations. This finding is consistent with taste-based theories of discrimination and with commitments made by large firms to hire actively from among low-caste groups.

Classed femininity, performativity, and camp in British structured reality programming

This article explores the representations and tonal qualities of British “structured reality” programming. Focusing on The Only Way Is Essex and Made in Chelsea, it investigates their glocalizing of the model established by MTV’s Laguna Beach and The Hills. It argues that while they blur boundaries between docusoap, drama, and soap opera, the British programs also recognize and foreground issues of construction for their reality TV-literate youth audience. It suggests the programs play a key role in their respective channel identities and the ideologies of British youth television, connecting to larger issues of class, gender, and taste. This is articulated through their regional and classed femininities, with the article exploring how the programs draw on classed ideologies surrounding “natural” and “excessive” femininities and of the role of this in their engagement with construction and camp play. This play contributes to the tonal shift offered by the British programs, mixing the melodrama of the MTV programs with a knowing, at times comic edge that can tip into mockery. In doing so, the programs offer their audience a combination of performative self-awareness and emotional realism that situates them clearly within British youth television

Increased neural processing of rewarding and aversive food stimuli in recovered anorexia nervosa

Background Recent evidence has shown that individuals with acute anorexia nervosa and those recovered have aberrant physiological responses to rewarding stimuli. We hypothesized that women recovered from anorexia nervosa would show aberrant neural responses to both rewarding and aversive disorder-relevant stimuli. Methods Using functional magnetic resonance imaging (fMRI), the neural response to the sight and flavor of chocolate, and their combination, in 15 women recovered from restricting-type anorexia nervosa and 16 healthy control subjects matched for age and body mass index was investigated. The neural response to a control aversive condition, consisting of the sight of moldy strawberries and a corresponding unpleasant taste, was also measured. Participants simultaneously recorded subjective ratings of “pleasantness,” “intensity,” and “wanting.” Results Despite no differences between the groups in subjective ratings, individuals recovered from anorexia nervosa showed increased neural response to the pleasant chocolate taste in the ventral striatum and pleasant chocolate sight in the occipital cortex. The recovered participants also showed increased neural response to the aversive strawberry taste in the insula and putamen and to the aversive strawberry sight in the anterior cingulate cortex and caudate. Conclusions Individuals recovered from anorexia nervosa have increased neural responses to both rewarding and aversive food stimuli. These findings suggest that even after recovery, women with anorexia nervosa have increased salience attribution to food stimuli. These results aid our neurobiological understanding and support the view that the neural response to reward may constitute a neural biomarker for anorexia nervosa.

Diminished neural processing of aversive and rewarding stimuli during selective serotonin reuptake inhibitor treatment

Background Selective serotonin reuptake inhibitors (SSRIs) are popular medications for anxiety and depression, but their effectiveness, particularly in patients with prominent symptoms of loss of motivation and pleasure, has been questioned. There are few studies of the effect of SSRIs on neural reward mechanisms in humans. Methods We studied 45 healthy participants who were randomly allocated to receive the SSRI citalopram, the noradrenaline reuptake inhibitor reboxetine, or placebo for 7 days in a double-blind, parallel group design. We used functional magnetic resonance imaging to measure the neural response to rewarding (sight and/or flavor of chocolate) and aversive stimuli (sight of moldy strawberries and/or an unpleasant strawberry taste) on the final day of drug treatment. Results Citalopram reduced activation to the chocolate stimuli in the ventral striatum and the ventral medial/orbitofrontal cortex. In contrast, reboxetine did not suppress ventral striatal activity and in fact increased neural responses within medial orbitofrontal cortex to reward. Citalopram also decreased neural responses to the aversive stimuli conditions in key “punishment” areas such as the lateral orbitofrontal cortex. Reboxetine produced a similar, although weaker effect. Conclusions Our findings are the first to show that treatment with SSRIs can diminish the neural processing of both rewarding and aversive stimuli. The ability of SSRIs to decrease neural responses to reward might underlie the questioned efficacy of SSRIs in depressive conditions characterized by decreased motivation and anhedonia and could also account for the experience of emotional blunting described by some patients during SSRI treatment.

Neural processing of reward and punishment in young people at increased familial risk of depression

Background Abnormalities in the neural representation of rewarding and aversive stimuli have been well-described in patients with acute depression, and we previously found abnormal neural responses to rewarding and aversive sight and taste stimuli in recovered depressed patients. The aim of the present study was to determine whether similar abnormalities might be present in young people at increased familial risk of depression but with no personal history of mood disorder. Methods We therefore used functional magnetic resonance imaging to examine the neural responses to pleasant and aversive sights and tastes in 25 young people (16–21 years of age) with a biological parent with depression and 25 age- and gender-matched control subjects. Results We found that, relative to the control subjects, participants with a parental history of depression showed diminished responses in the orbitofrontal cortex to rewarding stimuli, whereas activations to aversive stimuli were increased in the lateral orbitofrontal cortex and insula. In anterior cingulate cortex the at-risk group showed blunted neural responses to both rewarding and aversive stimuli. Conclusions Our findings suggest that young people at increased familial risk of depression have altered neural representation of reward and punishment, particularly in cortical regions linked to the use of positive and negative feedback to guide adaptive behavior.

Interpersonal interaction and economic theory: the case of public goods

Interpersonal interaction in public goods contexts is very different in character to its depiction in economic theory, despite the fact that the standard model is based on a small number of apparently plausible assumptions. Approaches to the problem are reviewed both from within and outside economics. It is argued that quick fixes such as a taste for giving do not provide a way forward. An improved understanding of why people contribute to such goods seems to require a different picture of the relationships between individuals than obtains in standard microeconomic theory, where they are usually depicted as asocial. No single economic model at present is consistent with all the relevant field and laboratory data. It is argued that there are defensible ideas from outside the discipline which ought to be explored, relying on different conceptions of rationality and/or more radically social agents. Three such suggestions are considered, one concerning the expressive/communicative aspect of behaviour, a second the possibility of a part-whole relationship between interacting agents and the third a version of conformism.

An experiment on spatial competition with endogenous pricing

Hotelling's (1929) principle of minimum differentiation and the alternative prediction that firms will maximally differentiate from their rivals in order to relax price competition have not been explicitly tested so far. We report results from experimental spatial duopolies designed to address this issue. The levels of product differentiation observed are systematically lower than predicted in equilibrium under risk neutrality and compatible with risk aversion. The observed prices are consistent with collusion attempts. Our main findings are robust to variations in three experimental conditions: automated vs. human market sharing rule for ties, individual vs. collective decision making, and even vs. odd number of locations.

The lottery-panel task for bi-dimensional parameter-free elicitation of risk attitudes

We propose first, a simple task for the eliciting attitudes toward risky choice, the SGG lottery-panel task, which consists in a series of lotteries constructed to compensate riskier options with higher risk-return trade-offs. Using Principal Component Analysis technique, we show that the SGG lottery-panel task is capable of capturing two dimensions of individual risky decision making i.e. subjects’ average risk taking and their sensitivity towards variations in risk-return. From the results of a large experimental dataset, we confirm that the task systematically captures a number of regularities such as: A tendency to risk averse behavior (only around 10% of choices are compatible with risk neutrality); An attraction to certain payoffs compared to low risk lotteries, compatible with over-(under-) weighting of small (large) probabilities predicted in PT and; Gender differences, i.e. males being consistently less risk averse than females but both genders being similarly responsive to the increases in risk-premium. Another interesting result is that in hypothetical choices most individuals increase their risk taking responding to the increase in return to risk, as predicted by PT, while across panels with real rewards we see even more changes, but opposite to the expected pattern of riskier choices for higher risk-returns. Therefore, we conclude from our data that an “economic anomaly” emerges in the real reward choices opposite to the hypothetical choices. These findings are in line with Camerer's (1995) view that although in many domains, paid subjects probably do exert extra mental effort which improves their performance, choice over money gambles is not likely to be a domain in which effort will improve adherence to rational axioms (p. 635). Finally, we demonstrate that both dimensions of risk attitudes, average risk taking and sensitivity towards variations in the return to risk, are desirable not only to describe behavior under risk but also to explain behavior in other contexts, as illustrated by an example. In the second study, we propose three additional treatments intended to elicit risk attitudes under high stakes and mixed outcome (gains and losses) lotteries. Using a dataset obtained from a hypothetical implementation of the tasks we show that the new treatments are able to capture both dimensions of risk attitudes. This new dataset allows us to describe several regularities, both at the aggregate and within-subjects level. We find that in every treatment over 70% of choices show some degree of risk aversion and only between 0.6% and 15.3% of individuals are consistently risk neutral within the same treatment. We also confirm the existence of gender differences in the degree of risk taking, that is, in all treatments females prefer safer lotteries compared to males. Regarding our second dimension of risk attitudes we observe, in all treatments, an increase in risk taking in response to risk premium increases. Treatment comparisons reveal other regularities, such as a lower degree of risk taking in large stake treatments compared to low stake treatments and a lower degree of risk taking when losses are incorporated into the large stake lotteries. Results that are compatible with previous findings in the literature, for stake size effects (e.g., Binswanger, 1980; Antoni Bosch-Domènech & Silvestre, 1999; Hogarth & Einhorn, 1990; Holt & Laury, 2002; Kachelmeier & Shehata, 1992; Kühberger et al., 1999; B. J. Weber & Chapman, 2005; Wik et al., 2007) and domain effect (e.g., Brooks and Zank, 2005, Schoemaker, 1990, Wik et al., 2007). Whereas for small stake treatments, we find that the effect of incorporating losses into the outcomes is not so clear. At the aggregate level an increase in risk taking is observed, but also more dispersion in the choices, whilst at the within-subjects level the effect weakens. Finally, regarding responses to risk premium, we find that compared to only gains treatments sensitivity is lower in the mixed lotteries treatments (SL and LL). In general sensitivity to risk-return is more affected by the domain than the stake size. After having described the properties of risk attitudes as captured by the SGG risk elicitation task and its three new versions, it is important to recall that the danger of using unidimensional descriptions of risk attitudes goes beyond the incompatibility with modern economic theories like PT, CPT etc., all of which call for tests with multiple degrees of freedom. Being faithful to this recommendation, the contribution of this essay is an empirically and endogenously determined bi-dimensional specification of risk attitudes, useful to describe behavior under uncertainty and to explain behavior in other contexts. Hopefully, this will contribute to create large datasets containing a multidimensional description of individual risk attitudes, while at the same time allowing for a robust context, compatible with present and even future more complex descriptions of human attitudes towards risk.