The brain: Different expert systems propose strategies for action, keeping track of the precision of the predictions within each system, exerting control over many different expert systems simultaneously to produce sophisticated behavior

Why and how the brain weights contributions from a mixture of experts. John P. O’Doherty et al. Neuroscience & Biobehavioral Reviews, January 11 2021. https://doi.org/10.1016/j.neubiorev.2020.10.022

Rolf Degen's take: https://twitter.com/DegenRolf/status/1348683591333670914

Highlights

• The brain can be thought of as a “Mixture of Experts” in which different expert systems propose strategies for action.

• This is accomplished by keeping track of the precision of the predictions within each system, and by allocating control over behavior in a manner that depends on the relative reliability of those predictions.

• This reliability-based control mechanism is domain general, exerting control over many different expert systems simultaneously in order to produce sophisticated behavior.

Abstract: It has long been suggested that human behavior reflects the contributions of multiple systems that cooperate or compete for behavioral control. Here we propose that the brain acts as a “Mixture of Experts” in which different expert systems propose strategies for action. It will be argued that the brain determines which experts should control behavior at any one moment in time by keeping track of the reliability of the predictions within each system, and by allocating control over behavior in a manner that depends on the relative reliabilities across experts. fMRI and neurostimulation studies suggest a specific contribution of the anterior prefrontal cortex in this process. Further, such a mechanism also takes into consideration the complexity of the expert, favoring simpler over more cognitively complex experts. Results from the study of different expert systems in both experiential and social learning domains hint at the possibility that this reliability-based control mechanism is domain general, exerting control over many different expert systems simultaneously in order to produce sophisticated behavior.

Keywords: cognitive controlPrefrontal cortexbasal gangliaTheoretical neuroscienceDecision-making

Conclusion

Here we outline a framework for conceptualizing the contribution of multiple systems to behavioral control in the human brain. We suggest that the brain utilizes a framework loosely analogous to the mixture of experts in machine learning, in which a prefrontal-based manager (which we hypothesize specifically involves the ventrolateral prefrontal cortex), reads out the reliability of the predictions by each of the constituent experts, and uses these predictions to allocate control over behavior to the experts in a manner that is proportional to the relative precision or uncertainties in their predictions. We suggest that this reliability-based arbitration process between experts is both necessary and sufficient for the efficient allocation of control between systems, as this approach takes into account not only the accuracy and hence the average expected value of the actions nominated by each expert, but also implicitly takes into account the cognitive costs and cognitive constraints. The interaction between systems that makes up the experts is we suggest, better conceived of as one of polling the advice from different systems that each have different relevant expertise that can and should be respected owing to differences in the nature of the information that is being processed, and in the algorithmic transformations that are performed on that information. These experts should be listened to as a collective, because they provide the right mixture of opinions needed to act in the world effectively.

Our results suggest that the theory cannot fully explain human aesthetic responses to flowers and clear preferences for them

Hula, M., & Flegr, J. (2021). Habitat Selection and Human Aesthetic Responses to Flowers. Evolutionary Human Sciences, 1-49. doi:10.1017/ehs.2020.66

Abstract: Although the aesthetic appreciation of flowers is a well-known aspect of human behaviour, theories explaining its origin are missing. The only exception is the evolutionary theory of Heerwagen and Orians. Surprisingly, it has not yet been empirically tested. The authors suggest that humans aesthetically respond to flowers because they signal food availability. The logic of the theory implies that fruits are more reliable and direct food availability signals than flowers. Therefore, fruits should elicit stronger aesthetic responses than flowers. To test this assumption, we performed two online studies in the Czech Republic. The participants (n = 2792 and 744 respectively) indicated on a six-point scale their aesthetic response to photographs of 14 edible Czech plant species (study A) and 20 edible plant species from African savannas (study B), varying in growth stage (flowering, fruiting). We found no difference between the Czech fruiting and flowering plants and a stronger aesthetic response to African flowering plants. A third study (n = 816) confirmed that flowers were preferred to fruits, using a forced-choice paradigm. Our results suggest that the theory cannot fully explain human aesthetic responses to flowers. We discuss alternative explanations. This topic deserves renewed attention from researchers working in related fields.

Social Media summary: Contrary to the assumptions of the habitat selection theory, flowers elicit stronger aesthetic responses than fruits.

Keywords: evolutionary aesthetics, habitat selection, flower preference, perception of flowers

Sexual prejudice toward gays is rooted in working-class experiences; contrary to mainstream ideas, social class matters in contemporary society, the relationship is not spurious, & education is not the main issue

Class Foundations of Sexual Prejudice toward Gay and Lesbian People. Stef Adriaenssens, Jef Hendrickx & Johanna Holm. Sexuality Research and Social Policy, Jan 11 2021. https://rd.springer.com/article/10.1007/s13178-020-00525-y

Abstract

Introduction: Sexual prejudice negatively affects the quality of life and life chances of those involved. Manual workers are consistently found to be less accepting of homosexuality in studies of sexual conformism. This can be seen as an application of Lipset’s ‘working class conformism’. Our core hypothesis is that this lower tolerance is rooted in working-class experiences. Counter-arguments are that that social class does not matter in contemporary society and that the relationship is spurious, with education as the true cause.

Methods: We test the central hypothesis with European survey data. First, we regress sexual prejudice on time trends and class with repeated cross-sections from the European Social Survey, ranging from 2002 to 2016. As an extra check, this is also applied to the European Values Study, going back to 1981. Further, we test the spuriousness argument with a matching design, testing whether stratification accounts for the lag.

Results: The time series shows a stable lag between working-class members and others against the general trend of decreasing sexual prejudice. The matching design provides evidence that working-class membership in itself is a factor behind differences in sexual prejudice.

Conclusions: Contrary to ‘death of class’ conjectures, working-class membership is related to sexual prejudice. This contribution shows that this gap is due to experiences of belonging to the working class and not solely to educational differences.

Policy Implications: Occupational experiences, especially in low-skill manual labour, have social effects in areas such as sexual prejudice. Improving the quality of work thus facilitates a more inclusive society for sexual minorities.

Chimpanzees stopped bartering when the human no longer mediated the trade; the authors think that the issue holding them back was an inability to trust their partners & a lack of third party enforcement mechanisms

What behaviour in economic games tells us about the evolution of non-human species' economic decision-making behaviour. Sarah F. Brosnan. Philosophical Transactions of the Royal Society B: Biological Sciences, Volume 376, Issue 1819, January 11 2021. https://doi.org/10.1098/rstb.2019.0670

Rolf Degen's take: https://twitter.com/DegenRolf/status/1348531514955460609

Abstract: In the past decade, there has been a surge of interest in using games derived from experimental economics to test decision-making behaviour across species. In most cases, researchers are using the games as a tool, for instance, to understand what factors influence decision-making, how decision-making differs across species or contexts, or to ask broader questions about species’ propensities to cooperate or compete. These games have been quite successful in this regard. To what degree, however, do these games tap into species' economic decision-making? For the purpose of understanding the evolution of economic systems in humans, this is the key question. To study this, we can break economic decision-making down into smaller components, each of which is a potential step in the evolution of human economic behaviour. We can then use data from economic games, which are simplified, highly structured models of decision-making and therefore ideal for the comparative approach, to directly compare these components across species and contexts, as well as in relation to more naturalistic behaviours, to better understand the evolution of economic behaviour and the social and ecological contexts that influenced it. The comparative approach has successfully informed us about the evolution of other complex traits, such as language and morality, and should help us more deeply understand why and how human economic systems evolved.

Check also Acquisition of object-robbing behavior in macaques: After stealing inedible & more or less valuable objects from humans, they appear to use them as tokens, by returning them to humans in exchange for food

Acquisition of object-robbing and object/food-bartering behaviours: a culturally maintained token economy in free-ranging long-tailed macaques. Jean-Baptiste Leca, Noëlle Gunst, Matthew Gardiner and I. Nengah Wandia. Philosophical Transactions of the Royal Society B: Biological Sciences, Volume 376, Issue 1819, January 11 2021. https://www.bipartisanalliance.com/2021/01/acquisition-of-object-robbing-behavior.html

4. What can we say about the evolution of economic systems?

Economic games are a model system that allows for close comparisons across contexts and species [46]. However, they are not intended to be natural situations, thus the data generated are best used to test hypotheses generated from observational or experimental work and generate new hypotheses that may be tested with more species-specific and/or naturalistic approaches [8]. While this can be done in diverse ways, there are two literatures that obviously connect to the existing data on experimental economics, that on cooperation and that on trade. Both literatures are extensive enough for entire reviews on their own, but I briefly discuss them as they tie into the main points raised above.

The assurance game highlights the fact that not all species coordinate, and even among those that do, coordination may be achieved by different underlying mechanisms. This reflects their behaviour in natural contexts as well. For instance, in capuchins, group territorial defence (i.e. [47]) and coordinated defence against predators (i.e. snake mobbing: [48]) are typically done among individuals with a clear view of one another and in situations in which all individuals are performing similar actions. This is reminiscent of capuchins’ behaviour in the Assurance game, in which they appeared to coordinate by matching their partners, and only achieved coordination when they could see the other's outcomes. This suggests that behaviour matching is a key mechanism for coordination in capuchins, possibly facilitated by behavioural synchrony and/or social facilitation. Indeed, although capuchins in experimental contexts can solve coordination tasks that require different actions (i.e. [41]), this was a rather simple case in which individuals could see one another and performed actions that they previously learned individually as a sequence.

On the other hand, chimpanzees show more complex coordinated behaviour, such as the coordinated hunting in which different individuals take on different roles, seen in some populations [49], which presumably requires an ability to understand the larger picture. This, too, matches their behaviour in the economic games, in which at least some chimpanzees (those with extensive experience with cognitive tasks) extrapolated to novel options in coordination games, suggesting that they understood their choice as part of a larger strategy. In some experimental contexts, too, chimpanzees show evidence of understanding the bigger picture, for instance choosing to benefit, at a cost to themselves, a chimpanzee that previously paid a cost to make that choice available [44]. Such specificity in how they make decisions suggests that they see their choice within a broader framework.

This synchrony between the outcomes of the highly structured economic games and these primates' natural behaviours suggests that the games are indeed useful models. They allow for studying mechanisms that may be impossible to study in more natural situations and for comparison across populations or species, and may be particularly helpful if differences in body form or ecology make it impossible to compare in more naturalistic contexts. Within the same population or species, these games can also be used to generate new hypotheses regarding behaviour, and the mechanisms underlying it, in more naturalistic contexts. Future work using more naturalistic experimental tasks, like the cooperative barpull (reviewed in [50]), or field-based experiments (as has been done in social learning research; [51]) that combine the naturalistic contexts of the observational work with the structured methodology of the economic games will help determine the limits and flexibility of the different species’ coordination ability and the cognitive mechanisms that underlie them.

We can similarly learn from how primates trade goods and services. Primates' ability to find the NE in economic games suggests that they should be able to maximize their outcomes in barter, too. Indeed, in natural contexts, primates do trade, although typically this involves services (grooming, support in conflicts, and mating opportunities) rather than goods (there are exceptions; for instance, chimpanzees trade meat for mating opportunities and support; [52]). There are several possible reasons for this; objects are zero sum commodities, and few items in primates’ natural lives are worth trading, as most are either easy to acquire or cannot be stored for future trades [5]. This does suggest, however, that they should trade objects when it is worth doing so, and indeed, in experimental tasks, primates trade tokens with experimenters (or, sometimes, other primates) in order to obtain different food rewards (see Addessi et al. [53] and Beran & Parrish [54]). Some macaques have even spontaneously developed exchange systems with humans in free-ranging contexts [55].

What is notably absent, however, is the transfer of these barter relationships with humans to trade with one another. We tested this among three highly trained chimpanzees at Georgia State's Language Research Center (the same chimpanzees that showed evidence of strategy use in the Assurance game). These chimpanzees had been taught a symbol language that allowed us to communicate with more specificity than is typically possible [56]. We made tokens representing specific foods (labelled by their symbol) that they could exchange back to an experimenter for food if—and only if—that food was present in their personal bin. In a series of tasks, we then explored whether the chimpanzees would learn to trade tokens that were of no value to them (because the food was not in their bin) to a partner to whom the tokens were valuable (because the food was in the partner's bin) so as to maximize both chimpanzees' benefits [57].

To cut a long story short, the chimpanzees learned to do so effectively as long as a human experimenter mediated the interactions such that neither chimpanzee could exchange a token with the experimenter for food until they had reciprocated any trades from the partner (we did not restrict which token they had to trade to a partner, just that they traded something). Despite having previously maximized their rewards, within one session of us removing experimenter-mediated quid pro quo, the chimpanzees ceased trading any tokens with their partners. Since they demonstrated all of the necessary cognitive abilities to understand trade, we hypothesized that the issue holding them back was an inability to trust their partners and a lack of third party enforcement mechanisms to make doing so worthwhile [57].

In concert with the results from experimental games, this suggests that at least some primates have the cognitive ability to understand these strategies and maximize their outcomes, which may be evident in service markets, but lack the enforcement mechanisms that lead to beneficial trade of goods. This is important for two reasons. First, it suggests that even these very structured, artificial laboratory situations are indeed useful for understanding the true scope of primates’ abilities, by removing factors that may inhibit expression. Second, this suggests that primates have a more developed set of abilities related to economic behaviour than is necessarily indicated in their natural behaviour. This not only guides future research aimed at understanding economic behaviour in natural contexts, but suggests that humans' abilities are not as separate from the other primates' as we might think. Indeed, this isn't the only context in which experimental tasks have revealed such similarities; primates also share psychological adaptations related to economic decision-making, such as the endowment effect [58] and framing effects [59,60]. Increasing evidence suggests that other species have the cognitive toolkit for economic behaviour and simply lack the opportunity to use it.

If this is the case, our next step is twofold. First, we must explore the range of economic behaviours in other species, ideally with the goal of delineating possible underlying cognitive mechanisms, and determine the contexts in which animals show these behaviours and how they are influenced by changes in social and ecological context. This will require creative experimental studies (both in the laboratory and, hopefully, in the field) to unpack what underlying abilities are present and when they manifest, as well as observational research to determine if related behaviours are seen in more natural contexts [61]. Indeed, further work in this area will also help to clarify the degree to which these abilities were selected specifically for this context versus others. Second, to more fully understand the cognitive precursors to economic behaviour, we also need to look beyond the primates. Although there has been work in this direction already, with studies of economic game behaviour in species as diverse as birds [62], rodents [63] and fish [64,65], even in those cases the focus has been on one or a few species. A more diverse approach is important for understanding how economic behaviour evolved; species vary in their needs, so a broad exploration will inform our understanding of the contexts, environments and pressures that selected for different economic behaviours. Ultimately, this will clarify how these abilities expanded so greatly in humans to result in the complex economic systems we enjoy today.

After group conversations, people underestimated how much they were liked by others; people focus on negative aspects of the impressions they make on others

The liking gap in groups and teams. Adam M. Mastroianni et al. Organizational Behavior and Human Decision Processes, Volume 162, January 2021, Pages 109-122. https://doi.org/10.1016/j.obhdp.2020.10.013

Rolf Degen's take: https://twitter.com/DegenRolf/status/1348524602255880192

Highlights

• After group conversations, people underestimated how much they were liked by others.

• This liking gap persisted in engineering teams working together on group projects.

• The effect was larger among peers than between supervisors and supervisees.

• The liking gap also had important consequences in a general sample of working adults.

• Consequences include team communication and efficacy as well as job satisfaction.

Abstract: Every relationship begins with a conversation. Past research suggests that after initial conversations, there exists a liking gap: people underestimate how much their partners like them. We extend this finding by providing evidence that it arises in conversations among small groups (Study 1), continues to exist in engineering teams working on a project together (Study 2), and is linked to important consequences for teams’ ability to work together in a sample of working adults (Study 3). Additional evidence suggests that the liking gap is largest for peer relationships and that it is determined in part by the extent to which people focus on negative aspects of the impressions they make on others. Group conversations and team interactions often leave people feeling uncertain about where they stand with others, but our studies suggest that people are liked more than they know.

Keywords: ConversationSocial interactionRelationship formationMeta-perceptionGroup dynamicsTeams

Acquisition of object-robbing behavior in macaques: After stealing inedible & more or less valuable objects from humans, they appear to use them as tokens, by returning them to humans in exchange for food

Acquisition of object-robbing and object/food-bartering behaviours: a culturally maintained token economy in free-ranging long-tailed macaques. Jean-Baptiste Leca, Noëlle Gunst, Matthew Gardiner and I. Nengah Wandia. Philosophical Transactions of the Royal Society B: Biological Sciences, Volume 376, Issue 1819, January 11 2021. https://doi.org/10.1098/rstb.2019.0677

Abstract: The token exchange paradigm shows that monkeys and great apes are able to use objects as symbolic tools to request specific food rewards. Such studies provide insights into the cognitive underpinnings of economic behaviour in non-human primates. However, the ecological validity of these laboratory-based experimental situations tends to be limited. Our field research aims to address the need for a more ecologically valid primate model of trading systems in humans. Around the Uluwatu Temple in Bali, Indonesia, a large free-ranging population of long-tailed macaques spontaneously and routinely engage in token-mediated bartering interactions with humans. These interactions occur in two phases: after stealing inedible and more or less valuable objects from humans, the macaques appear to use them as tokens, by returning them to humans in exchange for food. Our field observational and experimental data showed (i) age differences in robbing/bartering success, indicative of experiential learning, and (ii) clear behavioural associations between value-based token possession and quantity or quality of food rewards rejected and accepted by subadult and adult monkeys, suggestive of robbing/bartering payoff maximization and economic decision-making. This population-specific, prevalent, cross-generational, learned and socially influenced practice may be the first example of a culturally maintained token economy in free-ranging animals.

4. Discussion

This field observational and experimental study of token-robbing and token/reward-bartering interactions in the free-ranging population of Balinese long-tailed macaques produced three main findings: (i) these behaviours need to be learned throughout juvenescence (i.e. until up to 4 years in this species) to be successfully performed; (ii) older monkeys preferentially selected tokens that were more valued by humans; and (iii) these more skilful and selective individuals appeared to make economic decisions, as evidenced by clear behavioural associations between value-based token possession and quantity or quality of food rewards rejected and accepted.

(a) Experiential learning

As predicted, we found a significant increase in token-robbing success from juveniles to subadults to adults, whereas the main behaviour patterns required for the successful performance of token/reward-bartering interactions were already in place from around 4 years (i.e. in subadults). Likewise, the ability to engage in more negotiated successful token/reward-bartering sequences—during which the monkey only returned the token after being proposed more food rewards, or after rejecting more food rewards, or after accepting a type of food reward different from the one(s) previously rejected—was not fully acquired before the subadult stage.

These results lend some support to the ‘experiential learning' hypothesis, whereby token-robbing and token/reward-bartering interactions are multi-stepped and complex behavioural sequences requiring perceptual learning, sensorimotor coordination and cognitive skills (e.g. memory, associative learning) to be successfully performed; they are thus gradually acquired through extended individual practice during the juvenile period, in part via experiential trial-and-error learning. It is noteworthy to mention that the development of (sub)adult-level proficiency at robbing/bartering is not only dependent on skill learning (e.g. detection, sneaky approach, self-control), but may also be constrained by physical maturation. This is particularly true during the token-robbing phase that often involves monkey–human body contact and/or requires muscular strength when a monkey has to yank on a flip-flop still worn by an adult human. In these cases, the limited physical capabilities of juveniles, and the maturing bodies of subadults, may partly explain the significant increase in token-robbing success from juveniles to subadults to adults.

Primates are characterized by the longest juvenile period in relation to life span of all mammals [20]. According to the ‘needing-to-learn' hypothesis [20], prolonged juvenility is associated with behavioural patterns that necessitate acquiring a proportionally large amount of information and/or skills to reach adult competence before individuals become reproductively mature. These behaviours include extractive foraging techniques [21] and (socio-)sexual behaviour patterns [22]. Our study indicates that both phases of the robbing/bartering practice also required experiential learning to be fully mastered.

(b) Value-based token selection

The first step in economic decision-making requires the cognitive ability to distinguish among different expected material values of a given symbolic currency (e.g. tokens, cash, virtual money). After showing that token selection was not significantly affected by token availability and the relative ease with which different types of tokens were stolen by the monkeys from human targets, our observational data revealed a marked age difference in how the monkeys responded to a human-based three-level hierarchy of valuable objects. When considering the token selection among all the prospective human targets (i.e. temple visitors with potential tokens available in a given area), juveniles did not show any preferential selection among low-valued, medium-valued and high-valued tokens, whereas subadults and adults preferentially selected high- and medium-valued tokens over low-valued ones. When two tokens of different values were available on a given human target, subadults and adults preferentially selected the higher-value token, whereas juvenile individuals did not show any significant difference. We found a similar age difference in the value-based token selection, after experimentally controlling for token accessibility and lateral bias.

These results support the ‘value-based token selection' hypothesis, positing age differences in the selection of higher-valued tokens by the monkeys during the token-robbing phase that are indicative of a developmental trajectory toward more strategic choices in more mature individuals. Subadult and adult monkeys (but not juveniles yet) have learned to map their token-robbing behaviours onto the hierarchical (and arbitrary) scale of values attributed by humans to different tokens: they preferentially selected tokens that were more likely to be exchanged for food (e.g. electronic devices, pairs of glasses) over other objects that were less valuable for humans and typically not worth bartering (e.g. empty camera bags, hairpins). Our findings are consistent with data obtained in other non-human primate species, showing that subadult and adult capuchin monkeys and chimpanzees correctly preferred a high-valued token over a low-valued token in an experimental bartering situation [1,11,23].

(c) Robbing/bartering payoff maximization

The second step in economic decision-making requires the cognitive ability (i.e. mental processes involving associative learning and memorization) to respond differently to differentially valued tokens by trying to maximize one's payoff. We found evidence for such behavioural associations between value-based token possession and quantity or quality of food rewards rejected and accepted by subadult and adult monkeys (i.e. the most skilful and selective individuals) during the token/reward-bartering phase. They consistently and actively obtained either more food rewards or a more preferred food reward in exchange for a higher-valued token. They were also more likely to end a successful bartering interaction by accepting a less preferred food reward in exchange for a lower-valued token.

Our findings support the ‘robbing/bartering payoff maximization' hypothesis in that subadult and adult monkeys strategically responded to differentially valued tokens in their possession by adjusting the amount or type of food rewards they gained from the barters. The result showing that subadults (unlike adults) failed to significantly reject more low-preferred food rewards before returning a higher-valued token may be explained in terms of poorer temporal cognition or higher impulsivity (compared to adults): subadult long-tailed macaques may either not have yet acquired the cognitive capacity to anticipate the subsequent proffering of more preferred food rewards in this specific situation, or not be patient/self-controlled enough to wait for possibly more preferred food rewards.

Overall, our field observational data are in line with laboratory-based studies showing that several non-human primate species can (i) understand the effectiveness of tokens as secondary reinforcements to make simple calculations about quantities of reward, (ii) determine an item's value on the basis of its perceived utility (e.g. exchanging only a low-preferred reward for a tool necessary to reach a more preferred reward) and (iii) recognize the appropriate conditions in which a successful exchange could occur (e.g. presence/absence of the experimenter, safe/risky experimenter) [1,2,23–27]. Other cognitive skills and temperamental traits exhibited to varying extents by non-human primates engaging in token-aided economic behaviours include preference transitivity, self-control, delay of gratification, action planning and calculated reciprocity, because they may facilitate or constrain an individual's ability to make optimal economic decisions [1,5,23,28]. Even though these characteristics were not explicitly examined in this study, some of them will be the subject of our future observational and experimental investigations.

The origins of human variation in human economic behaviour: Comparative studies of other primates can help disentangle the relative role of shared biological processes vs human-unique cultural influences in risk preferences

Variation in primate decision-making under uncertainty and the roots of human economic behaviour. Francesca De Petrillo and Alexandra G. Rosati. Philosophical Transactions of the Royal Society B: Biological Sciences, Volume 376, Issue 1819, January 11 2021. https://doi.org/10.1098/rstb.2019.0671

Rolf Degen's take: https://twitter.com/DegenRolf/status/1348516690167029766

Abstract: Uncertainty is a ubiquitous component of human economic behaviour, yet people can vary in their preferences for risk across populations, individuals and different points in time. As uncertainty also characterizes many aspects of animal decision-making, comparative research can help evaluate different potential mechanisms that generate this variation, including the role of biological differences or maturational change versus cultural learning, as well as identify human-unique components of economic decision-making. Here, we examine decision-making under risk across non-human primates, our closest relatives. We first review theoretical approaches and current methods for understanding decision-making in animals. We then assess the current evidence for variation in animal preferences between species and populations, between individuals based on personality, sex and age, and finally, between different contexts and individual states. We then use these primate data to evaluate the processes that can shape human decision-making strategies and identify the primate foundations of human economic behaviour.

5. Conclusion: primate decision-making and human economic origins

Humans exhibit great variation in responses to risk across populations, individuals and contexts, so understanding the origins of this variation is crucial to explaining patterns of human economic behaviour. We have argued that comparative studies of decision-making can disentangle the mechanisms and the function of this variation to address questions about both the proximate mechanisms and the ultimate consequences of these decision-making patterns. As such, non-human primates provide a complementary line of evidence to test hypotheses about the origins of human economic behaviours (figure 2).

Figure 2. The origins of human variation in human economic behaviour. Comparative studies of other primates can help disentangle the relative role of shared biological processes versus human-unique cultural influences in risk preferences. Current evidence for variation across populations, individuals and contexts in primates suggests some processes are shared with humans whereas others are human-unique.

We found that non-humans sometimes show patterns of variation like those in humans. For example, emotional states, social context and some neurotransmitter systems can modulate risk preferences in primates like in humans. This suggests that at least some of the proximate psychological mechanisms driving human economic behaviour build upon cognitive, emotional and neurobiological substrates that are shared with other primates Yet other mechanisms may be more specific to humans: while humans show robust gender differences in risk preferences as well as developmental change over the life-course, there is limited evidence for parallel shifts in non-human risky choice. This suggests that this variation may stem more from human-specific mechanisms, such as cultural learning and socialization. Given that culturally based traits are more malleable and thus more amenable to interventions, this provides new clues for promoting optimal economic behaviour in humans.

A second question concerns the ultimate consequences of variation in risk preferences. Here, comparative work can provide an important line of evidence to test the adaptive consequences of different strategies. For example, there are robust species differences in responses to risk indicating that species that typically feed on more variable, heterogeneous resources are relatively more risk-seeking. Yet there are also crucial differences in human and animal patterns that may stem from humans' novel socioecological niche. Human hunter–gatherer lifestyles are characterized by a dependence on high-value and high-risk foods that may have required new social mechanisms to cope with a greater variability in foraging, such as food sharing and resource redistribution [107,116]. As a consequence, humans might have evolved new cognitive abilities and innovated new cultural practices to deal with the social risks presented by exchanges.

Yet there is still much work to be done. First, different species and questions have sometimes been tested using different tasks (figure 1), limiting some inferences across studies. In addition, primate studies, in general, are often limited by small sample sizes, especially with respect to questions of intra-individual variation. As such, comparisons of decision-making using standardized methods in larger populations with wider variation in sex, ages or particular life experiences are crucial to test these ideas. Finally, the animal choice typically involves biologically relevant rewards, but there is increasing evidence that people can be more risk-seeking when making ‘foraging’ decisions about food than in equivalent decisions involving money [67,103]. Given that humans engage in evolutionarily novel forms of economic exchange involving abstract currencies, but other primates can be trained to use and exchange tokens in specific contexts [84], animals thus present untapped opportunities to test how experience with markets impacts economic decision-making. More generally, comparative research is well-positioned to advance our understanding of human economic behaviour by pinpointing the necessary cognitive and experiential prerequisites that enable different aspects of decision-making and exchange.

Hyper-altruistic Behavior Vanishes with High Stakes: Individuals decrease the donated fraction of the pie as the stakes increase; hyper-altruistic behavior seems an artifact of the typical stakes used in lab work

Branas-Garza, Pablo, Diego A. Jorrat, Jaromir Kovarik, and Maria C. Lopez. 2021. “Hyper-altruistic Behavior Vanishes with High Stakes.” PsyArXiv. January 10. doi:10.31234/osf.io/b79e4

Rolf Degen's take: https://twitter.com/DegenRolf/status/1348330565150375944

Abstract: Using a powered and incentivized experiment, this paper explores the role of stakes in charitable giving of lottery prizes, where subjects commit to donate a fraction of the prize before they learn the outcome of the lottery. We study three stake levels: 5€ (n = 177), 100€ (n = 168), and 1,000€ (n = 171). We find that individuals decrease the donated fraction of the pie as the stakes increase. However, people still share roughly 20% of 1,000€, an amount as high as the average monthly salary of people at the age of our subjects. We further report that the number of people sharing 50% of the pie is remarkably stable across stakes but donating the whole pie -the modal behavior in charity-donation experiments- disappears with stakes. Such hyper-altruistic behavior thus seems to be an artifact of the stakes typically employed in economic and psychological experiments. Our findings point out that sharing with others is a prevalent human feature, but stakes are an important determinant of sharing and policies frequently promoted via prosocial frames (such as stressing the effects of mask-wearing or social distancing on others during the ongoing Covid-19 pandemic or environmentally-friendly behaviors on future generations) may thus be miscalibrated if they disregard the stakes at play.

Perceptions of physical attractiveness: Smiling images were rated as more attractive (regardless of stimulus motion format); PPAs were based more on the perceiver than on either the target or format in which the target was presented

In the Eye of the Beholder: A Comprehensive Analysis of Stimulus Type, Perceiver, and Target in Physical Attractiveness Perceptions. Molly A. Bowdring, Michael A. Sayette, Jeffrey M. Girard & William C. Woods. Journal of Nonverbal Behavior, Jan 9 2021. https://rd.springer.com/article/10.1007/s10919-020-00350-2

Abstract: Physical attractiveness plays a central role in psychosocial experiences. One of the top research priorities has been to identify factors affecting perceptions of physical attractiveness (PPA). Recent work suggests PPA derives from different sources (e.g., target, perceiver, stimulus type). Although smiles in particular are believed to enhance PPA, support has been surprisingly limited. This study comprehensively examines the effect of smiles on PPA and, more broadly, evaluates the roles of target, perceiver, and stimulus type in PPA variation. Perceivers (n = 181) rated both static images and 5-s videos of targets displaying smiling and neutral-expressions. Smiling images were rated as more attractive than neutral-expression images (regardless of stimulus motion format). Interestingly, perceptions of physical attractiveness were based more on the perceiver than on either the target or format in which the target was presented. Results clarify the effect of smiles, and highlight the significant role of the perceiver, in PPA.

Quantum money, which has recently been partially implemented in an experimental setting, offers the privacy & anonymity of physical cash, & the option to transact without the involvement of a third party

Quantum Technology for Economists. Isaiah Hull, Or Sattath, Eleni Diamanti3, and Goran Wendin. Sveriges Riksbank Working Paper Series, No. 398. December 2020. https://www.riksbank.se/globalassets/media/rapporter/working-papers/2019/no.-398-quantum-technology-for-economists.pdf

Abstract: Research on quantum technology spans multiple disciplines: physics, computer science, engineering, and mathematics. The objective of this manuscript is to provide an accessible introduction to this emerging field for economists that is centered around quantum computing and quantum money. We proceed in three steps. First, we discuss basic concepts in quantum computing and quantum communication, assuming knowledge of linear algebra and statistics, but not of computer science or physics. This covers fundamental topics, such as qubits, superposition, entanglement, quantum circuits, oracles, and the no-cloning theorem. Second, we provide an overview of quantum money, an early invention of the quantum communication literature that has recently been partially implemented in an experimental setting. One form of quantum money offers the privacy and anonymity of physical cash, the option to transact without the involvement of a third party, and the efficiency and convenience of a debit card payment. Such features cannot be achieved in combination with any other form of money. Finally, we review all existing quantum speedups that have been identified for algorithms used to solve and estimate economic models. This includes function approximation, linear systems analysis, Monte Carlo simulation, matrix inversion, principal component analysis, linear regression, interpolation, numerical differentiation, and true random number generation. We also discuss the difficulty of achieving quantum speedups and comment on common misconceptions about what is achievable with quantum computing.

Keywords: Quantum Computing, Econometrics, Computational Economics, Money, Central Banks.

JEL Classification: C50, C60, E40, E50.

Adjusting for absolute body mass index, individuals with high relative BMI are more likely to report low levels of life satisfaction; the link between relative BMI & life satisfaction is similar for both men & women

Assessing the importance of relative body weight in shaping life satisfaction: Evidence from 1 million Americans. Jinho Kim. Current Psychology, Jan 9 2021. https://rd.springer.com/article/10.1007/s12144-021-01360-z

Rolf Degen's take: https://twitter.com/DegenRolf/status/1347875756676943873

Abstract: Using data from the 2005–2008 Behavioral Risk Factor Surveillance System, this study shows that an individual’s ordinal body mass index (BMI) rank in a reference group is an important determinant of life satisfaction. This study finds that, adjusting for absolute BMI, individuals with high relative BMI are more likely to report low levels of life satisfaction. This relationship depends on group-specific social comparisons (i.e., within race/ethnic groups), especially for women. This study also shows that the link between relative BMI and life satisfaction is similar for both men and women, and persists into old age. Among women, the negative association between relative BMI and life satisfaction is driven largely by those residing in urban areas. No such patterns are found among men. To make further progress in understanding the relationship between BMI and psychological health and well-being, it is essential to consider how the meaning of an individual’s body weight might differ in reference to others’ body weight.

Playboy and Pornification: 65 Years of the Playboy Centerfold

Playboy and Pornification: 65 Years of the Playboy Centerfold. Hannah Regan. Sexuality & Culture, Jan 9 2021. https://rd.springer.com/article/10.1007/s12119-020-09809-2

Rolf Degen's take: https://twitter.com/DegenRolf/status/1347827683598737408

Abstract: In the more than 6 decades since its founding, Playboy magazine has had to contend with a great deal of cultural change, most significantly the rise of the Internet pornography industry. The magazine, particularly its signature centerfold, the Playmate of the Month, has had to adapt accordingly. In this visual analysis, I review 65 years of Playboy centerfolds to consider how their bodies—physical characteristics, positions, contexts, and explicitness—have changed, and how this reflects the broader social change to which they are subject. I find that, overall, very little changes over the years, with two notable exceptions: increased visibility of the montes pubis and the slow decreasing in the amount of pubic hair the models have, and the brief time period in which the magazine attempted to remove nudity altogether. My results show that the magazine appears to place more value on staying true to the Playboy image than to adapting to a new market and has continued to be a recognized symbol of gender and sexuality even in light of decreasing readership and publication.

Buying local: This paper's main finding is that these justifications fail to provide a strong positive ethical reason for consumers in general to adopt the practice

Should You Buy Local? Carson Young. Journal of Business Ethics, Jan 3 2021. https://link.springer.com/article/10.1007/s10551-020-04701-3

Abstract: Buying local is a prominent form of ethical consumption. We commonly assume that products that are local are in some respect ethically superior to ones that are not. This article contributes to research on local food by scrutinizing this assumption in light of some central values of the locavore movement. It identifies four central ethical causes from prior literature on locavorism: protecting the environment, promoting community, promoting small business, and contributing to the prosperity of one’s local economy. It then analyzes whether the contribution of buying local to these causes can justify the general perception that buying local is a good way to be an ethical consumer. Its main finding is that these justifications fail to provide a strong positive ethical reason for consumers in general to adopt the practice of buying local.

On one hand, an informed citizenry is allegedly necessary for a democracy to flourish; on the other hand, the most knowledgeable and passionate voters are also the most likely to think in corrupted, biased ways

Are Smarter Voters Better Voters? Michael Hannon. PhilPapers, Jan 2021. https://philpapers.org/rec/HANASV

Abstract: It is widely believed that democracies require knowledgeable citizens to function well. But the most politically knowledgeable individuals also tend to be the most partisan and the strength of partisan identity tends to corrupt political thinking. This creates a conundrum. On one hand, an informed citizenry is allegedly necessary for a democracy to flourish. On the other hand, the most knowledgeable and passionate voters are also the most likely to think in corrupted, biased ways. What to do? This paper examines this tension and draws out several lessons. First, it is not obvious that more knowledgeable voters will make better political decisions. Second, worries about voter ignorance may be misguided because partisans tend to become more dogmatic when they acquire more information. Third, ‘epistocratic’ solutions that emphasize voter knowledge are troubling, in part, because they increase the political power of the most dogmatic and biased individuals. Fourth, I suggest that solutions to citizen incompetence should focus less on voter knowledge and more on the intellectual virtue of objectivity. Unfortunately, a likely way to foster political objectivity is by encouraging political apathy.

Keywords: political knowledge  political ignorance  motivated reasoning  epistocracy  objectivity  partisan bias

The Primacy of Morality in Impression Development: Sociability (e.g., friendliness & likeability) or competence are less important than morality (e.g., honesty & trustworthiness) in our valuations of persons or groups

The Primacy of Morality in Impression Development: Theory, Research, and Future Directions. Marco Brambilla et al. Advances in Experimental Social Psychology 64, Jan 2021. https://www.researchgate.net/publication/348190223

Rolf Degen's take: https://twitter.com/DegenRolf/status/1347782969738539009

Abstract: Over the past few decades, two-factor models of social cognition have emerged as a dominant framework for understanding impression development. These models suggest that two dimensions-warmth and competence-are key in shaping our cognitive, emotional, and behavioral reactions toward social targets. More recently, research has jettisoned the warmth dimension, distinguishing instead between sociability (e.g., friendliness and likeability) and morality (e.g., honesty and trustworthiness) and showing that morality is far more important than sociability (and competence) in predicting the evaluations we make of individuals and groups. Presenting research from our laboratories, we show that moral categories are central at all stages of impression development, from implicit assumptions, to information gathering and to final evaluations. Moreover, moral trait information has a dominant role in predicting people's behavioral reactions toward social targets. We also show that morality dominates impression development, because it is closely linked to the essential judgment of whether another party's intentions are beneficial or harmful. Thus, our research informs a new framework for understanding person and group perception: the Moral Primacy Model (MPM) of impression development. We conclude by discussing how the MPM relates to classic and emerging models of social cognition and by outlining a trajectory for future research.

The overconfidence transmission effect persisted over time & task domains, elevating overconfidence even days after initial exposure; may be in part responsible for why local confidence norms emerge in groups/teams/organizations

Cheng, J. T., Anderson, C., Tenney, E. R., Brion, S., Moore, D. A., & Logg, J. M. (2021). The social transmission of overconfidence. Journal of Experimental Psychology: General, 150(1), 157–186. https://doi.org/10.1037/xge0000787

Abstract: We propose and test the overconfidence transmission hypothesis, which predicts that individuals calibrate their self-assessments in response to the confidence others display in their social group. Six studies that deploy a mix of correlational and experimental methods support this hypothesis. Evidence indicates that individuals randomly assigned to collaborate in laboratory dyads converged on levels of overconfidence about their own performance rankings. In a controlled experimental context, observing overconfident peers causally increased an individual’s degree of bias. The transmission effect persisted over time and across task domains, elevating overconfidence even days after initial exposure. In addition, overconfidence spread across indirect social ties (person to person to person), and transmission operated outside of reported awareness. However, individuals showed a selective in-group bias; overconfidence was acquired only when displayed by a member of one’s in-group (and not out-group), consistent with theoretical notions of selective learning bias. Combined, these results advance understanding of the social factors that underlie interindividual differences in overconfidence and suggest that social transmission processes may be in part responsible for why local confidence norms emerge in groups, teams, and organizations.

Ageing in Better Mental Health

Ageing in Better Mental Health. Marisa Cordella, Aldo Poiani. Fulfilling Ageing pp 201-354, January 5 2021. https://link.springer.com/chapter/10.1007/978-3-030-60071-6_4

Abstract: This develops the topic of Ageing in better health. Here we return to the biology of ageing, that was first introduced in Chap. 1, but with a special emphasis on brain plasticity, a very important topic that is the focus of a fast-developing research program, and we also review psychological health in old age. Initially mentally healthy persons may be at risk of experiencing serious deterioration of their mental capacities as they age; therefore, we devote a section in this chapter to review mental pathologies in the elderly. Special emphasis is given to the analysis of the various forms of dementia, including Alzheimer’s disease. From there we proceed to address those aspects of ageing that affect sexual behaviour. The challenges experienced by people with a disability (mental or physical) who are becoming older are also the topic of a section in this chapter. We conclude the chapter with a section devoted to older people who reach very advanced ages: the centenarians, semi-supercentenarians, and supercentenarians.

From 1999... Availability cascade is a belief formation process by which an expressed perception triggers a chain reaction that gives the perception of increasing plausibility through its rising availability in public discourse

Kuran, Timur and Sunstein, Cass R., Availability Cascades and Risk Regulation. Stanford Law Review, Vol. 51, No. 4, 1999, U of Chicago, Public Law Working Paper No. 181, U of Chicago Law & Economics, Olin Working Paper No. 384, https://ssrn.com/abstract=138144

Abstract: An availability cascade is a self-reinforcing process of collective belief formation by which an expressed perception triggers a chain reaction that gives the perception of increasing plausibility through its rising availability in public discourse. The driving mechanism involves a combination of informational and reputational motives: Individuals endorse the perception partly by learning from the apparent beliefs of others and partly by distorting their public responses in the interest of maintaining social acceptance. Availability entrepreneurs - activists who manipulate the content of public discourse - strive to trigger availability cascades likely to advance their agendas. Their availability campaigns may yield social benefits, but sometimes they bring harm, which suggests a need for safeguards. Focusing on the role of mass pressures in the regulation of risks associated with production, consumption, and the environment, Professor Timur Kuran and Cass R. Sunstein analyze availability cascades and suggest reforms to alleviate their potential hazards. Their proposals include new governmental structures designed to give civil servants better insulation against mass demands for regulatory change and an easily accessible scientific database to reduce people's dependence on popular (mis)perceptions.

Keywords: availability heuristic, informational cascades, reputational cascades, cost-benefit analysis

JEL Classification: L51, K23

Previous research has found that women at peak fertility show greater interest in extra-pair sex; however, recent replications have failed to detect this effect

Current Fertility Status Does Not Predict Sociosexual Attitudes and Desires in Normally Ovulating Women. Andrew G. Thomas.  Evolutionary Psychology,January 8, 2021. https://doi.org/10.1177/1474704920976318

Abstract: Previous research has found that women at peak fertility show greater interest in extra-pair sex. However, recent replications have failed to detect this effect. In this study, we add to this ongoing debate by testing whether sociosexuality (the willingness to have sex in the absence of commitment) is higher in women who are at peak fertility. A sample of normally ovulating women (N = 773) completed a measure of sociosexuality and had their current fertility status estimated using the backward counting method. Contrary to our hypothesis, current fertility was unrelated to sociosexual attitudes and desires, even when relationship status was included as a moderator. These findings raise further doubts about the association between fertility and desire for extra-pair sex.

Keywords: ovulatory shift hypothesis, sociosexuality, menstrual cycle, mate preferences, extra-pair mating

Discussion

The purpose of this study was to test the idea, derived from the ovulatory shift and dual-mating hypotheses (Gangestad & Thornhill, 1998; Penton-Voak et al., 1999), that women’s mating strategies change in accordance with fluctuations in fertility across the menstrual cycle. To do so we used a between-subjects sample of normally ovulating women to examine whether current fertility status could predict sociosexual desires and attitudes. Our hypothesis was not supported. No relationship was found between fertility status and attitude or desire subscales of the SOI-R. In fact, the β observed in the regression predicting sociosexual desire was in the opposite direction to that predicted (β = −.04). Exploratory analyses showed that the null effect of fertility persisted when relationship status was added to the models as a moderator. We did find that older women reported higher numbers of past partners and acts of uncommitted sex, but only if they were currently high in fertility. We did not predict this weak association and see no theoretical reason for it. Given that this effect also disappeared when covariates were added to the model (see Footnote 1) we are inclined to believe this to be a Type I error.

It is possible that the null results obtained in this study are due to the methodological issues outlined previously. The ‘gold standard’ in menstrual cycle research is to use within-subjects designs and to establish fertility status using hormonal measurements (Gangestad et al., 2016). Our study, in contrast, used a between-subjects design with self-reported cycle data and non-verified bleed-dates. Nonetheless, there are several reasons to be confident that our results are not due to a Type II error.

First, the sample size is large and surpasses the minimum requirement set out by both Gangestad et al. (2016) and Jones et al. (2019) for a sufficiently-powered between-subjects study. Second, as recommended by Gangestad et al. (2016), fertility status was not determined using high and low fertility windows, but instead measured along a continuous scale of conception risk (Wilcox et al., 2001). Finally, we employed a backwards-counting method to determine day of cycle. Due to the large degree of variability in the follicular phase compared to the comparatively consistent length of the luteal phase (Fehring et al., 2006), the backwards-counting method is the most reliable way to obtain self-report menstrual cycle data.

The results of this study converge with other recent well-powered between-subject investigations into the ovulatory-shift hypothesis (Dixson et al., 2018; Marcinkowska et al., 2018b) and within-subjects studies using hormonal measures (Jünger et al., 2018; Marcinkowska et al., 2018a). However, it should be noted that some studies suggest that fertility-related shifts in mating psychology depend on relationship status and on factors within a relationship, such as the attractiveness of one’s current partner (Haselton & Gangestad, 2006; Pillsworth & Haselton, 2006). We did not have data about perceived partner attractiveness for partnered women in our dataset, but we were able to include their relationship status in our models. Doing so did not qualitatively alter the role of fertility status. It is worth noting, however, that this exploratory analysis was underpowered. A full understanding of this moderation effect would have required us to examine sub-groups of single and pair-bonded women, effectively halving the sample. The two studies that report an effect of partner attractiveness were also both underpowered (see the calculations of Gangestad et al., 2016; Jones et al. (2019). Therefore, future research should investigate the role of relationship moderators on fertility effects in sufficiently large samples to test these hypotheses adequately.

Further consideration should be given to the role of sociosexuality in acquiring extra-pair partners. There is an established relationship between sociosexuality and infidelity (Barta & Kiene, 2005). Thus, it is reasonable to expect that waxing interest in casual sex would facilitate acts of extra-pair infidelity and that this may form part of an ovulatory shift mechanism that functions to shift mating effort away from a primary partner and toward another. However extra-pair liaisons are not exclusively casual and may involve feelings of love and commitment, such as in cases of mate-switching (Buss et al., 2017). To the extent that uncommitted sex is not a strict prerequisite for extra-pair relationships, we cannot rule out the possibility of dual-mating mechanisms in humans based solely on an absence of relationship between within-cycle fertility and SO. Potential future research could consider forgoing sociosexuality for more implicit indicators of relationship commitment, including motivated biases favoring one’s partner (e.g., positive partner illusions) or derogating alternatives (Finkel et al., 2017).

In sum, these null results raise further doubts about the hypothesized association between fertility and desire for extra-pair sex, and more specifically the role of sociosexuality as a potential moderator of this process. Should extra-pair desire change across the menstrual cycle, then this may be context specific and/or facultative. Such changes may be difficult to detect at a general group level, emphasizing the importance of well-powered within-subject designs that both use hormonal verification to reduce measurement error and take relationship context and motivation into account.