Bad riddance or good rubbish? Ownership and not loss aversion causes the endowment effect

Information search under uncertainty across transdiagnostic psychopathology and healthy ageing

When making decisions in everyday life, we often rely on an internally generated sense of confidence to help us revise and direct future behaviours. For instance, confidence directly informs whether further information should be sought prior to commitment to a final decision. Many studies have shown that aging and both clinical and sub-clinical symptoms of psychopathology are associated with systematic alterations in confidence. However, it remains unknown whether these confidence distortions influence information-seeking behaviour. We investigated this question in a large general population sample (N = 908). Participants completed a battery of psychiatric symptom questionnaires and performed a perceptual decision-making task with confidence ratings in which they were offered the option to seek helpful information (at a cost) before committing to a final decision. Replicating previous findings, an 'anxious-depression' (AD) symptom dimension was associated with systematically low confidence, despite no detriment in objective task accuracy. Conversely, a 'compulsive behaviour and intrusive thoughts' (CIT) dimension was associated with impaired task accuracy but paradoxical over-confidence. However, neither symptom dimension was significantly associated with an increased or decreased tendency to seek information. Hence, participants scoring highly for AD or CIT did not use the option to information seek any more than average to either increase their confidence (AD) or improve the accuracy of their decisions (CIT). In contrast, older age was associated with impaired accuracy and decreased confidence initially, but increased information seeking behaviour mediated increases in both accuracy and confidence for final decisions. Hence, older adults used the information seeking option to overcome initial deficits in objective performance and to increase their confidence accordingly. The results show an appropriate use of information seeking to overcome perceptual deficits and low confidence in healthy aging which was not present in transdiagnostic psychopathology.

Impact of Implementing Psychological Ownership in Undergraduate Dental Clinical Training: A Retrospective Study

Purpose

The idea of psychological ownership (PO) has been utilized in a variety of contexts, but the significance and lessons learned from using PO in dental clinical education have not been investigated. A detailed long-term study of PO in dental clinical education will allow us to understand the effectiveness of this practice. The purpose of this paper is to compare undergraduate (UG) student's clinical performance before and after the PO system was implemented.

Materials and methods

A retrospective study was conducted with around 70-80 students in an academic year from June 2012 to June 2019. Through ownership quality, four-handed dentistry, observation and assistance, supply of must-haves, and measurable outcomes, the clinical performance of students in pre- and post-PO systems was compared.

Results

The quantum of overall clinical procedures performed by the UG students was 8,214 and 13,753 in pre-PO and post-PO, respectively. Chi-squared tests performed unveil that there exists a statistically significant difference in the quantum of clinical procedures performed by UG after the implementation of PO.

Conclusion

The results of our study clearly state that there was a significant increase in the quantum of clinical procedures performed by UG students after the implementation of the PO system.

How to cite this article

Felsypremila G, Muthu MS, Nirmal L, et al. Impact of Implementing Psychological Ownership in Undergraduate Dental Clinical Training: A Retrospective Study. Int J Clin Pediatr Dent 2024;17(3):279-284.

The art of the deal: Deciphering the endowment effect from traders' eyes

People are often reluctant to trade, a reticence attributed to the endowment effect. The prevailing account attributes the endowment effect to valuation-related bias, manifesting as sellers valuing goods more than buyers, whereas an alternative account attributes it to response-related bias, manifesting as both buyers and sellers tending to stick to the status quo. Here, by tracking and modeling eye activity of buyers and sellers during trading, we accommodate both views within an evidence-accumulation framework. We find that valuation-related bias is indexed by asymmetric attentional allocation between buyers and sellers, whereas response-related bias is indexed by arousal-linked pupillary reactivity. A deal emerges when both buyers and sellers attend to their potential gains and dilate their pupils. Our study provides preliminary evidence for our computational framework of the dynamic processes mediating the endowment effect and identifies physiological biomarkers of deal-making.

Collective psychological ownership as a new angle for understanding group dynamics

Even without legal ownership, groups can experience objects, places, and ideas as belonging to them ('ours'). This state of mind-collective psychological ownership-is understudied in social psychology, yet it is central to many intergroup conflicts and stewardship behaviour. We discuss our research on the psychological processes and social-psychological implications of collective psychological ownership. We studied territorial ownership, in different parts of the world and at different geographical levels, offering not only a cross-national but also conceptual replication of the processes. Our findings show that collective psychological ownership is inferred based on primo-occupancy, investment, and formation. Further, we demonstrate that collective psychological ownership can have positive intragroup and negative intergroup outcomes, which are guided by perceived group responsibility and exclusive determination right. We then discuss ownership threat (losing what is 'ours'), and we consider the role of group identification in ownership-related processes. We conclude by providing directions for future research.

Neural correlates of overvaluation and the effort to save possessions in a novel decision task: An exploratory fMRI study

Introduction

People exhibit a strong attachment to possessions, observed in behavioral economics through loss aversion using new items in the Endowment or IKEA effects and in clinical psychology through pathological trouble discarding domestic items in Hoarding Disorder. These fields rarely intersect, but both document a reticence to relinquish a possessed item, even at a cost, which is associated with feelings of loss but can include enhanced positive states as well.

Methods

To demonstrate the shared properties of these loss-related ownership effects, we developed the Pretzel Decorating Task (PDT), which concurrently measures overvaluation of one's own over others' items and feelings of loss associated with losing a possession, alongside enhanced positive appraisals of one's items and an effort to save them. The PDT was piloted with 31 participants who decorated pretzels and responded to their own or others' items during functional neuroimaging (fMRI). Participants observed one item per trial (self or other) and could work to save it (high or low probability loss) before learning the fate of the item (trashed or saved). Finally, participants rated items and completed hoarding tendency scales.

Results

The hypotheses were supported, as even non-clinical participants overvalued, viewed as nicer, feared losing, and worked harder to save their items over others'-a response that correlated with hoarding tendencies and motor-motivational brain activation. Our region of interest in the nucleus accumbens (NAcc) was engaged when viewing one's own items to the extent that people worked harder to save them and was more active when their items were saved when they felt emotionally attached to possessions in real life. When their items were trashed, NAcc activity negatively correlated with trouble discarding and emotional attachments to possessions. Right anterior insula was more active when working to save one's own over others' items. Extensive motor-motivational areas were engaged when working to save one's own over others' items, including cerebellum, primary motor and somatosensory regions, and retrosplenial/parahippocampal regions-even after controlling for tapping.

Discussion

Our attachments to items are emotional, continuous across typical and pathological populations, and drive us to save possessions that we value.

The Relationship between Environmental Awareness, Habitat Quality, and Community Residents' Pro-Environmental Behavior-Mediated Effects Model Analysis Based on Social Capital

Pro-environmental behavior can promote the optimization of the living environment and sustainable social development. This paper constructs a theoretical analysis framework of "environmental consciousness, habitat environment-social capital- pro-environmental behavior". By using structural equation modeling and 1005 instances of microscopic research data, we analyzed the influence of environmental awareness and habitat environment on the pro-environmental behavior of community residents. The results of the analysis were combined with the Bootstrap method to verify the mediating role of social capital dimensions in the influence of environmental awareness and habitat quality on the pro-environmental behavior of community residents. The results show that: Firstly, environmental awareness, habitat quality, and social capital have positive effects on the pro-environmental behavior of community residents. Secondly, environmental awareness and habitat quality have positive effects on the five dimensions of social capital. Thirdly, among the five dimensions of social capital, four dimensions of social trust, social norms, sense of community belonging, and community voluntarism play a partially mediating role between environmental awareness, habitat quality, and pro-environmental behavior. This paper enriches the research on the influence of environmental awareness and habitat environment on pro-environmental behavior, reveals the mediating effect of each dimension of social capital, and broadens the horizon for the study of pro-environmental behavior. The results of the study can provide a reference for decision making to promote the implementation of pro-environmental behavior among community residents.

Leaving the Homestead: Examining the Role of Relative Deprivation, Social Trust, and Urban Integration among Rural Farmers in China

Actively promoting the orderly and voluntary withdrawal of idle rural house bases and effectively activating "sleeping" land assets are considered important measures to accelerate the modernization of agriculture and rural areas, as well as promoting the integrated development of urban and rural areas. However, few studies have focused on the superimposed effects of negative psychological and social environmental factors on the willingness of farmers to withdraw from their homestead. Therefore, we conducted this study in order to clarify the logical ideas of rural home base withdrawal, analyze the factors that influence the decision of home base withdrawal behavior of interest subjects, and provide a scientific decision basis for promoting rural home base withdrawal and accelerating the process of transferring citizens of agricultural population in terms of policies, measures, and paths, so as to design and develop an incentive mechanism for home base withdrawal of citizens of agricultural transfer population. The results of the study show that: (1) the findings indicate that social deprivation, economic deprivation, and emotional deprivation all significantly and negatively affect farmers' willingness to withdraw from their homesteads; (2) social trust plays a mediating role between relative deprivation and farmer homestead withdrawal behavior; and (3) urban integration plays a moderating role between social and emotional deprivation and the social trust of farmers, but does not have a significant moderating role in the relationship between economic deprivation and social trust. Furthermore, it plays a moderating role between all deprivation factors (i.e., economic, social, and emotional deprivation) and farmer homestead withdrawal behavior. This study aims to provide useful guidance and policy suggestions for optimizing policies related to farmer homestead withdrawal behaviors, and for scientifically designing the homestead withdrawal mechanism and policy system.

The endowment effect in the future: How time shapes buying and selling prices

Previous research has focused on studying the endowment effect for transactions that take place in the present. Many real-world transactions, however, are delayed into the future (i.e., people agree to buy or sell, but the actual transaction does not materialize until a later time). Here we investigate how transaction timing affects the endowment effect. In five studies, we show that the endowment effect systematically increases as transactions are delayed into the future. Specifically, buying prices significantly decrease as the transaction is delayed, while selling prices remain constant, resulting in an amplified endowment effect (Experiment 1). This pattern is not produced by a discounting of the money involved in the transaction (Experiment 2), and it holds across different types of items (Experiment 3). We also show that the phenomenon cannot be explained by sellers anticipating becoming increasingly attached to the items over time (Experiment 4). Finally, we demonstrate that this increased endowment effect in the future holds in the field, in the context of a real market and with real transactions (Experiment 5).

Development of a Japanese version of the Psychological Ownership Scale

The present study addresses the need for a valid instrument for measuring dimensions of psychological ownership, including that of owned and non-owned objects, for use in the language and culture of Japan. Although the theory of psychological ownership has expanded self-extension theory, the most widely used scale of psychological ownership does not measure the extent to which one feels that it (the owned object) is a part of them. Thus, the present study aimed to develop a Japanese version of the Psychological Ownership Scale (POS-J) and examine its reliability and validity. Study 1 measured the POS-J of an owned object, finding the POS-J to have a two-factor structure (possession-self link and feeling of ownership) and its internal consistency and reliability to be adequate. Moreover, POS-J scores were positively correlated with perceived control and self-extension tendency, but not monetary value, indicating that conceptual validity was generally supported. To confirm whether the POS-J could be used for a non-owned object, Study 2 rephrased the expressions of item descriptions and examined the effect of imagining touching a non-owned object on the POS-J scores, showing that doing so increased the POS-J scores for the object. Our findings suggest that the POS-J is a reliable and valid measure of the psychological ownership of owned and non-owned objects for use in Japan.

Willingness to accept (WTA), willingness to pay (WTP), and the WTA/WTP disparity in Chinese social media platforms: Descriptive statistics and associations with personality and social media use

The amount of money individuals were willing to accept (WTA) to discontinue using prominent Chinese social media platforms (WeChat/QQ), the willingness to pay (WTP) for using these platforms, as well as WTA/WTP disparities were investigated in between-groups and within-subjects design studies to examine their existence, size, and psychological correlates in the form of personality and social media use habits. Individuals were recruited at Chinese universities in three separate surveys. For between-groups investigations, four samples were investigated: WTA and WTP samples for investigations in the context of WeChat as well as WTA and WTP samples for QQ. For within-subjects investigations, individuals completed items on WTA and WTP for WeChat/QQ, the Big Five Inventory, time spent on WeChat/QQ, and the short Bergen Social Media Addiction Scale. Two samples providing data on WeChat and QQ, respectively, were investigated. Across study designs and for both WeChat and QQ we found evidence for high WTA and comparatively low WTP scores, thus, large WTA/WTP disparities. Individual differences in the disparities were negatively associated with Openness across social media platforms. The results reveal a generally low acceptance to pay for social media use, which is important against the background of discussions on monetary payment models. Moreover, a complex interplay between individual characteristics, characteristics of the service, and how and why the service is used seems to underly WTA and the WTA/WTP disparity. Finally, methodological implications of the present results for forthcoming studies assessing valuation (WTA, WTP) in the context of social media are discussed.

Mere Ownership Effect Is Equally Pronounced in Material and Immaterial Objects

Abstract. The mere ownership effect is an increase in the subjective value of owned objects compared to identical but non-owned objects. We tested whether the effect differs in magnitude between material and immaterial objects (e.g., information). Three hundred participants played an incentivized detective game in which they had to connect clues to identify a murderer. Their task was to evaluate the usefulness of the clues they or their partners were endowed with. Despite the fact that the immaterial clues were rated as more useful than the material ones, we found the mere ownership effect to be similarly strong for the material and the immaterial clues.

Buyers, Maybe Moving Second Is Not That Bad After All: Low-Power, Anxiety, and Making Inferior First Offers

The behavioral decision-making and negotiations literature usually advocates a first-mover advantage, explained the anchoring and adjustment heuristic. Thus, buyers, who according to the social norm, tend to move second, strive to make the first offer to take advantage of this effect. On the other hand, negotiation practitioners and experts often advise the opposite, i.e., moving second. These opposite recommendations regarding first offers are termed the Practitioner-Researcher paradox. In the current article, we investigate the circumstances under which buyers would make less favorable first offers than they would receive were they to move second, focusing on low power and anxiety during negotiations. Across two studies, we manipulated negotiators' best alternative to the negotiated agreement (BATNA) and measured their anxiety. Our results show that, when facing neutral-power sellers, weak buyers who feel anxious would make inferior first offers (Studies 1 and 2). When facing low-power sellers, weak buyers would make inferior first offers across all anxiety levels (Study 2). Our findings shed light on two critical factors leading to the Practitioner-Researcher paradox: power and anxiety, and offer concrete guidelines to buyers who find themselves at low power and highly anxious during negotiations.

Objects and self-identity

This article reviews how objects can serve as indicators of one's identity and signals of important life events. Objects carry both personal and social meaning, and ownership or usage increases the linkage between the object and the self. Owned objects are valued more due to their linkage with the (positively viewed) self. Similarly, self-views can assimilate to the associations of the owned or used object. We rely on the insights of consistency theories (e.g. Balance Theory) to provide a unifying umbrella for the literature, and we review how the acquisition and abandonment of objects can shape self-views, affect task performance, and serve as inward and outward signals of group membership.

Losing what is OURS: The intergroup consequences of collective ownership threat

Collective ownership threat is the fear of losing control over what is perceived to be owned. In two experimental studies, we examined the intergroup consequences of collective ownership threat in relation to perceived owned territories. First, among a sample of Dutch adolescents ( N = 227), we found that infringement of a hangout place owned by a group of friends led to more perceived collective ownership threat (and not symbolic threat), which was in turn related to more marking and anticipatory defending behavior. Second, among a sample of native Dutch adults ( N = 338), we found that framing Turkish EU accession as an infringement of the collective ownership of the country led to more perceived collective ownership threat (and not symbolic and economic threat), which was in turn related to more opposition to Turkey’s possible accession. Our findings indicate that collective ownership threat is an important construct to consider in intergroup research.

The gamification of in-game advertising: Examining the role of psychological ownership and advertisement intrusiveness

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Psychological factors impact gameful experience and the attitudes of online gamers.

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Gameful experience is positively linked with online gamers’ attitudes.

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Psychological ownership (PO) and perceived in-game advertisement effectiveness (PAE) positively mediate this path.

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Online gamers comprehend the effectiveness of in-game advertising.

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The impact of advertisement intrusiveness can be countered with high PAE and PO.

Gamification on the mobile platform through the concept of online games has the potential to create unprecedented engagement with customers. With the growth in the gamification market due to the increase in internet penetration and the number of mobile devices, it has become one of the potential channels to reach and influence young consumers who spend more time on gaming. There is a shortage of empirical evidence on the impact of gamification on online consumer decisions. This study uses ‘psychological ownership theory’ and ‘schema theory’ to examine the effects of gameful experience (GFUL) on the attitudes of online gamers (N = 326). Data were analyzed using AMOS 25 and Process Macro for SPSS. The analytical results indicated that GFUL is mediated through both the intervening variables (perceived in-game advertisement effectiveness and psychological ownership), which positively influence gamers’ attitudes towards the game and in-game advertising. Further, the study investigated the impact of in-game advertisement intrusiveness. Based on the research findings, this study proposed the theoretical and managerial implications.

Self-bias effect: movement initiation to self-owned property is speeded for both approach and avoidance actions

Recall of, and physical interaction with, self-owned items is privileged over items owned by other people (Constable et al. in Cognition 119(3):430-437, 2011; Cunningham et al. in Conscious Cognit 17(1):312-318, 2008). Here, we investigate approach (towards the item), compared with avoidance (away from the item) movements to images of self- and experimenter-owned items. We asked if initiation time and movement duration of button-press approach responses to self-owned items are associated with a systematic self-bias (overall faster responses), compared with avoidance movements, similar to findings of paradigms investigating affective evaluation of (unowned) items. Participants were gifted mugs to use, and after a few days they completed an approach-avoidance task (Chen and Bargh in Pers Soc Psychol Bull 25(2):215-224, 1999; Seibt et al. in J Exp Soc Psychol 44:713-720, 2008; Truong et al. in J Exp Psychol Hum Percept Perform 42(3), 375-385, 2016) to images of their own or the experimenter's mug, using either congruent or incongruent movement direction mappings. There was a self-bias effect for initiation time to the self-owned mug, for both congruent and incongruent mappings, and for movement duration in the congruent mapping. The effect was abolished in Experiment 2 when participants responded based on a shape on the handle rather than mug ownership. We speculate that ownership status requires conscious processing to modulate responses. Moreover, ownership status judgements and affective evaluation may employ different mechanisms.

The relationship between endowment and ownership effects in memory across cultures

An object one owns is typically more highly valued than an equivalent object owned by another person. This endowment effect has been attributed to the aversion of loss of one's possessions (through selling), or the added value of an item due to self-association (through owning). To date, investigation of these mechanisms has been hampered by the between-subjects methodology traditionally employed to measure endowment. Over two experiments, we report a novel within-subjects method for measuring an endowment bias. In these studies, Western participants showed enhanced valuation of owned items, whereas East-Asian participants did not. This endowment bias also correlated with the ownership effect in memory (a measure of self-referential processing) in Western, but not East-Asian participants. Our results suggest that the endowment effect is partly predicated on the same factors that influence the ownership effect and that this commonality is likely linked to conceptions of ownership specifically, and self-concept more generally.

The endowment effect in the genes: An exploratory study

The endowment effect is a well-documented decision phenomenon, referring to a tendency that people price a commodity higher when selling it than when buying it. This phenomenon can be interpreted as a sort of inertia, an unwillingness to make a change, or in other words an attachment to the status-quo. People with autism dislike social interaction, and are thus probably less willing to buy and sell items and more attached to the status quo. Previous research revealed that T-carriers of a single-nucleotide polymorphism (SNP) of the dopamine beta-hydroxylase (DBH) gene, rs1611115 (C-1021T), are associated with autism and difficulty in social interaction. Therefore, rs1611115 may modulate the endowment effect. In the current study, the subjects sold and bought lotteries with various probabilities of winning money and provided saliva for genotyping. We found that T-carriers (people of CT genotype in this study) exhibited greater endowment effects compared to people of CC genotype. We discuss another two possible explanations of our results: empathy and loss aversion. This is the first attempt to research the endowment effect from the perspective of genes. The result indicates that an SNP of genes (an innate factor) can exert an observable effect on human market activities.

Ownership Matters: People Possess a Naïve Theory of Ownership

Ownership is at the heart of people's daily activities and has been throughout history. People consider ownership when acting on objects, engaging in financial matters, and assessing the acceptability of actions. We propose that people's understanding of ownership depends on an early-emerging, causally powerful, naïve theory of ownership. We draw on research from multiple disciplines to suggest that, from childhood, a naïve theory of ownership includes ontological commitments, causal-explanatory reasoning, and unobservable constructs. These components are unlikely to stem from other core theories or from noncausal representations. We also address why people might have a naïve theory of ownership, how it develops across the lifespan, and whether aspects of this theory may be universal despite variation across cultures and history.

Social Rewards: From Basic Social Building Blocks to Complex Social Behavior

Humans are social creatures, engaging almost constantly in social behaviors that serve ultimate social goals, such as forming strong bonds with one another. However, most social behaviors provide only incremental progress toward an ultimate goal. Instead, the drive to engage in any individual social act may derive from its proximal value rather than its ultimate goal. Thus, this proximal value forms the foundation on which the complexities of human sociality are built. We describe two complementary approaches for using proximal social rewards to understand social behaviors and their ultimate goals: (a) decontextualizing social rewards—paring down complex social interactions can help identify which basic building blocks remain valuable even in minimalistic contexts—and (b) recontextualizing social rewards—reintroducing motivational and contextual factors into the study of social experience can help identify how proximal rewards serve their ultimate function. We discuss how this dual-approach framework can inform future research by bridging basic social building blocks and real-world social goals.

Unpacking buyer-seller differences in valuation from experience: A cognitive modeling approach

People often indicate a higher price for an object when they own it (i.e., as sellers) than when they do not (i.e., as buyers)-a phenomenon known as the endowment effect. We develop a cognitive modeling approach to formalize, disentangle, and compare alternative psychological accounts (e.g., loss aversion, loss attention, strategic misrepresentation) of such buyer-seller differences in pricing decisions of monetary lotteries. To also be able to test possible buyer-seller differences in memory and learning, we study pricing decisions from experience, obtained with the sampling paradigm, where people learn about a lottery's payoff distribution from sequential sampling. We first formalize different accounts as models within three computational frameworks (reinforcement learning, instance-based learning theory, and cumulative prospect theory), and then fit the models to empirical selling and buying prices. In Study 1 (a reanalysis of published data with hypothetical decisions), models assuming buyer-seller differences in response bias (implementing a strategic-misrepresentation account) performed best; models assuming buyer-seller differences in choice sensitivity or memory (implementing a loss-attention account) generally fared worst. In a new experiment involving incentivized decisions (Study 2), models assuming buyer-seller differences in both outcome sensitivity (as proposed by a loss-aversion account) and response bias performed best. In both Study 1 and 2, the models implemented in cumulative prospect theory performed best. Model recovery studies validated our cognitive modeling approach, showing that the models can be distinguished rather well. In summary, our analysis supports a loss-aversion account of the endowment effect, but also reveals a substantial contribution of simple response bias.

Thinking of me: Self-focus reduces sharing and helping in seven- to eight-year-olds

By 7-to 8-years of age, most children readily adhere to prosocial norms aimed at benefiting others through giving up time and effort (helping) or resources (sharing). Two studies explored whether sharing and helping by 7-to 8-year olds (N = 180) could be influenced by priming children's attention on themselves or their friends through a semi-structured interview. Results revealed that self-priming led to reductions in both sharing and helping compared to friendship-priming or a control condition. These findings are considered as indicative of the fragile state of prosocial behaviours at this age that can be easily shifted towards more selfish biases by simple priming.

Value-based choice: An integrative, neuroscience-informed model of health goals

OBJECTIVE

Traditional models of health behaviour focus on the roles of cognitive, personality and social-cognitive constructs (e.g. executive function, grit, self-efficacy), and give less attention to the process by which these constructs interact in the moment that a health-relevant choice is made. Health psychology needs a process-focused account of how various factors are integrated to produce the decisions that determine health behaviour.

DESIGN

I present an integrative value-based choice model of health behaviour, which characterises the mechanism by which a variety of factors come together to determine behaviour. This model imports knowledge from research on behavioural economics and neuroscience about how choices are made to the study of health behaviour, and uses that knowledge to generate novel predictions about how to change health behaviour. I describe anomalies in value-based choice that can be exploited for health promotion, and review neuroimaging evidence about the involvement of midline dopamine structures in tracking and integrating value-related information during choice. I highlight how this knowledge can bring insights to health psychology using illustrative case of healthy eating.

CONCLUSION

Value-based choice is a viable model for health behaviour and opens new avenues for mechanism-focused intervention.

Oxytocin Increases the Perceived Value of Both Self- and Other-Owned Items and Alters Medial Prefrontal Cortex Activity in an Endowment Task

The neuropeptide oxytocin (OXT) can influence self-processing and may help motivate us to value the attributes of others in a more self-like manner by reducing medial prefrontal cortex (mPFC) responses. We do not know however whether this OXT effect extends to possessions. We tend to place a higher monetary value on specific objects that belong to us compared to others, known as the "endowment effect". In two double-blind, between-subject placebo (PLC) controlled experiments in subjects from a collectivist culture, we investigated the influence of intranasal OXT on the endowment effect, with the second study incorporating functional magnetic resonance imaging (fMRI). In the task, subjects decided whether to buy or sell their own or others' (mother/father/classmate/stranger) possessions at various prices. Both experiments demonstrated an endowment effect in the self-owned condition which extended to close others (mother/father) and OXT increased this for self and all other-owned items. This OXT effect was associated with reduced activity in the ventral mPFC (vmPFC) in the self-owned condition but increased in the mother-condition. For the classmate- and stranger-owned conditions OXT increased activity in the dorsal mPFC (dmPFC). Changes in vmPFC activation were associated with the size of the endowment effect for self- and mother-owned items. Functional connectivity between the dmPFC and ventral striatum (VStr) was reduced by OXT in self- and mother-owned conditions and between vmPFC and precuneus in the self-condition. Overall our results show that OXT enhances the endowment effect for both self- and other-owned items in Chinese subjects. This effect is associated with reduced mPFC activation in the self-condition but enhanced activation in all other-conditions and involves differential actions on both dorsal and ventral regions as well as functional connectivity with brain reward and other self-processing regions. Overall our findings suggest that OXT increases the perceived value of both self- and other-owned items by acting on neural circuitry involved in self-processing and reward.

Ownership Effect Can Be a Result of Other-Derogation: Evidence from Behavioral and Electrophysiological Studies

Growing evidence suggests that people overvalue their own objects compared to those owned by others, even when the two objects are virtually identical (i.e., ownership effect). Most researchers seem to consider self-enhancement as the underlying mechanism while neglecting the possible process of other-derogation. Here, we attempted to compare these two perspectives, adopting both implicit and neurocognitive methodologies to overcome social desirability confounds. In Study 1, we found that the ownership effect (measured by Implicit Association Test), was correlated with other-derogation but not with self-enhancement (both measured by the Go/No-Go Association Task). In Study 2, by using the event-related potentials (ERPs) technique, we showed that positive-framed other-owned objects elicited significant evaluative incongruity (i.e. indexed by late positive potentials) compared to negative-framed other-owned objects. In contrast, negative-framed self-owned objects did not evoke significant evaluative incongruity relative to positive-framed self-owned objects. Our research suggests that, in addition to the self-enhancement that has been widely demonstrated, it is also important to keep other-derogation in mind when examining the ownership effect.

Trading experience modulates anterior insula to reduce the endowment effect

People often demand a greater price when selling goods that they own than they would pay to purchase the same goods-a well-known economic bias called the endowment effect. The endowment effect has been found to be muted among experienced traders, but little is known about how trading experience reduces the endowment effect. We show that when selling, experienced traders exhibit lower right anterior insula activity, but no differences in nucleus accumbens or orbitofrontal activation, compared with inexperienced traders. Furthermore, insula activation mediates the effect of experience on the endowment effect. Similar results are obtained for inexperienced traders who are incentivized to gain trading experience. This finding indicates that frequent trading likely mitigates the endowment effect indirectly by modifying negative affective responses in the context of selling.

Price Discrepancy Between Sellers and Buyers When Making Decisions for the Self and Others

In daily life, people make decisions not only for themselves but also on behalf of others. There may be differences in terms of the endowment effect when making decisions in these two situations. In Study 1, this question was investigated with an existing dataset exploring the traditional endowment effect, in which 86 students ( M age = 20.8 years, SD = 5.0) at Harvard University were asked to make a decision on selling or buying a coffee mug for themselves or for others as brokers. When making decisions for the self, the average price demanded by sellers was much higher than that offered by buyers; while making decisions for others, the price discrepancy disappeared. In Study 2, a similar study was conducted with a sample of 42 Chinese university students ( M age = 22.3 years, SD = 2.5), and a similar pattern of results was obtained. Further analysis indicated that when making decisions for others, only buyers increased their valuations, therefore mitigating the seller–buyer price discrepancy. Finally, the findings were interpreted from the perspective of Construal Level Theory.

Number preferences in lotteries

We explore people’s preferences for numbers in large proprietary data sets from two different lottery games. We find that choice is far from uniform, and exhibits some familiar and some new tendencies and biases. Players favor personally meaningful and situationally available numbers, and are attracted towards numbers in the center of the choice form. Frequent players avoid winning numbers from recent draws, whereas infrequent players chase these. Combinations of numbers are formed with an eye for aesthetics, and players tend to spread their numbers relatively evenly across the possible range.

The SPOT effect: People spontaneously prefer their own theories

People often exhibit confirmation bias: They process information bearing on the truth of their theories in a way that facilitates their continuing to regard those theories as true. Here, we tested whether confirmation bias would emerge even under the most minimal of conditions. Specifically, we tested whether drawing a nominal link between the self and a theory would suffice to bias people towards regarding that theory as true. If, all else equal, people regard the self as good (i.e., engage in self-enhancement), and good theories are true (in accord with their intended function), then people should regard their own theories as true; otherwise put, they should manifest a spontaneous preference for their own theories (i.e., a SPOT effect). In three experiments, participants were introduced to a theory about which of two imaginary alien species preyed upon the other. Participants then considered in turn several items of evidence bearing on the theory and each time evaluated the likelihood that the theory was true versus false. As hypothesized, participants regarded the theory as more likely to be true when it was arbitrarily ascribed to them as opposed to an "Alex" (Experiment 1) or to no one (Experiment 2). We also found that the SPOT effect failed to converge with four different indices of self-enhancement (Experiment 3), suggesting that it may be distinctive in character.