Context-dependent Preferences Research Articles

Selection for relative brain size affects context-dependent male preference for, but not discrimination of, female body size in guppies.

Understanding what drives animal decisions is fundamental in evolutionary biology, and mate choice decisions are arguably some of the most important in any individual's life. As cognitive ability can impact decision making, elucidating the link between mate choice and cognitive ability is necessary to fully understand mate choice. To experimentally study this link, we used guppies (Poecilia reticulata) artificially selected for divergence in relative brain size and with previously demonstrated differences in cognitive ability. A previous test in our female guppy selection lines demonstrated the impact of brain size and cognitive ability on information processing during female mate choice decisions. Here, we evaluated the effect of brain size and cognitive ability on male mate choice decisions. Specifically, we investigated the preference of large-brained, small-brained and non-selected guppy males for female body size, a key indicator of female fecundity in this species. For this, male preference was quantified in dichotomous choice tests when presented with dyads of females with small, medium and large body size differences. All types of males showed a preference for larger females but no effect of brain size was found in the ability to discriminate between differently sized females. However, we found that non-selected and large-brained males, but not small-brained males, showed a context-dependent preference for larger females depending on the difference in female size. Our results have two important implications. First, they provide further evidence that male mate choice also occurs in a species in which secondary sexual ornamentation is present only in males. Second, they show that brain size and cognitive ability have important effects on individual variation in mating preference and sexually selected traits.

Context-dependent preferences vary by multicomponent signals in a swordtail

Female mating preferences can be both context dependent and based on the assessment of multicomponent male signals. Here, we assess the social context dependence of female mating preferences for two components of a male's multicomponent signal. We dissected the visual signal of male Xiphophorus nigrensis swordtails, a species in which males vary by both size and degree of courtship, to test (1) how the identity of males in a given choice influences female mating preferences and (2) how females perceptually integrate a male's multicomponent signal. We used validated male animations that generate repeatable female responses to test mating preferences for size and courtship vigour, separately and together, using dichotomous choice tests. When keeping courtship vigour constant, females discriminated between males only when there was a large size difference between them. When keeping size constant, the identity of males in a choice reversed a preference for a vigorously courting male. We found no evidence that females perceptually bind the separate components of a male's signal additively. However, females were faster to approach males when the males varied in both size and courtship than when the males only varied in size, perhaps favouring the evolution of multicomponent signals in males.

Product Line Extension in Consumer Software Markets in the Presence of Free Alternatives

Hypercompetitive consumer software markets pit incumbents against free alternatives and pirates. Although the extant literature has studied firm level strategic responses to consumer heterogeneity and piracy, there is a lack of understanding of consumer reactions to digital goods choice sets that include firm product extensions such as the introduction of premium or free alternatives. With context-dependent preferences as the theoretical basis, this study systematically examines the impact of piracy controls and product line extensions on welfare in a consumer software market context (i.e., willingness to pay (WTP) and changes in consumer and producer surplus). In two controlled experiments using double-bound-dichotomous-choice WTP elicitation, we investigate how piracy controls and product line extensions impact two different platforms of the same software (PC Adobe applications and mobile Adobe applications) in terms of propensity to pirate and WTP. We show that introducing a premium or free vertical extension has different impacts on consumers’ WTP for the focal product depending on whether it is a low-cost or high-cost market even when controlling for individual differences, such as price fairness perceptions, product feature value, brand perceptions, etc. By contrast, piracy controls reduce piracy rates but have a limited impact on consumer WTP for the focal product in both contexts. By calculating the overall welfare of the market, we show that there is alignment in consumer and producer interests at current and estimated optimal price levels in both high-cost and low-cost markets. However, the introduction of a free product extension leads to a higher surplus in the high-cost market, whereas the introduction of the premium product extension leads to a higher surplus in the low-cost market.

Context-Dependent Preferences and the Right to Forgo Life-Saving Treatments

A member of Jehovah’s Witnesses agreed to receive blood when alone, but rejected it once the elders were present. She insisted that the elders should stay, they were allowed to do so, and she bled ...

An introduction to "Sugar and spice, and everything nice: exploring prosocial development through infancy and early childhood".

Prosocial behaviors begin to emerge at an early age (e.g., Damon, 1975; Rheingold et al., 1976; Eisenberg and Fabes, 1998; Thompson et al., 1997; Paulus, 2014). For example, helping behaviors are demonstrated by infants as young as 18 months of age (e.g., Warneken and Tomasello, 2006) and sharing behavior begins to emerge at around 2 years of age (e.g., Rheingold et al., 1976). Such prosociality is essential to social functioning in many respects. However, while prosocial behavior has long been of interest to developmental researchers, there remains much we do not know about the early development of prosocial behaviors. This research topic builds on a well-established area of research, and brings together the work of various researchers in the field of prosocial development who have contributed unique theoretical perspectives, insightful reviews, and novel empirical work. The goal of this research topic is to examine broadly how, why, and when a spectrum of behaviors emerge, and enhance our understanding of the beginnings of human prosociality. Here, the existing literature is reviewed, and new insights into the development of prosocial behaviors are offered. A broad range of topics such as helping, cooperation, sharing, inequality aversion, and moral reasoning are covered, and various factors influencing prosociality explored. As discussed in a theoretical contribution by Keith Jensen, Amrisha Vaish, and Marco Schmidt, prosociality is unique to humans and its development is influenced by a variety of mechanisms such as empathy, other-regarding concerns, and normativity. Importantly, the term prosocial behavior encompasses a multitude of behaviors, however, in her review article, Kristen Dunfield proposes that other-oriented, prosocial actions can be categorized into three specific subtypes; sharing, helping, and comforting, drawing on existing literature to support her proposal. These subtypes of prosocial behaviors are further explored in this research topic using a variety of approaches. For instance, helping in early childhood is explored in a theoretical contribution by Stuart Hammond. While Hammond discusses the development of early helping behavior using a Piagetian framework, helping is also explored empirically by Sunae Kim, Beate Sodian, and Markus Paulus, who investigate differences in children's expectations regarding instrumental helping and self-helping at different points in development. Other empirical contributions include work by Martina Vogelsang, Keith Jensen, Sebastian Kirschner, Claudio Tennie, and Michael Tomasello exploring cooperation in 5-year-olds using a public goods game, and a study by Sophia Ongley, Marta Nola, and Tina Malti demonstrating that moral reasoning is a strong predictor of the generosity of children's donations. Ongley and colleagues also explore how moral emotions such as sympathy and guilt relate to children's donating behavior, while several other experiments included in this research topic also explore various aspects of empathy and sympathy in early childhood. For instance, in a longitudinal study exploring the stability of sympathy over time, Jutta Kienbaum demonstrates that sympathy shows strong stability, and increases between the last year of preschool and the first year of school. Meanwhile, Jesse Drummond, Elena Paul, Whitney Waugh, Stuart Hammond and Celia Brownell show that empathic helping in toddlers is predicted by emotion and mental state talk, and Amanda Williams, Kelly O'Driscoll and Chris Moore demonstrate that experiencing empathic concern for another individual affects subsequent prosocial behavior; both decreasing envy, and increasing sharing. Other factors influencing prosociality and social interactions are also investigated. In a study exploring the motivations underlying preferences for equality in situations of disadvantageous inequality, Amanda Williams and Chris Moore offer evidence that in some situations social comparison concerns—as opposed to fairness norms, influence decision-making. Markus Paulus demonstrates that the wealth of one's sharing partner also influences 5-year-olds sharing behavior with that individual, while Monica Burns and Jessica Sommerville demonstrate that both fairness and race influence 15-month-old infants' selection of social partners. In a study looking at social preferences in an even younger sample, Kiley Hamlin demonstrates that even infants as young as 4.5 months display context-dependent social preferences, and selectivity in prosocial behavior is further discussed in a review paper by Valerie Kuhlmeier, Kristen Dunfield, and Amy O'Neill. Together this body of research demonstrates and discusses the complexities of a wide range of prosocial behaviors. It makes a significant contribution to the extant literature across a range of age groups, and a wide breadth of topics. It is our hope that the novel ideas, methodologies, and findings presented here help us better understand the development of early prosocial behavior as a whole, and stimulate and inspire future research.

Context-dependent group size preferences in large shoals of three-spined sticklebacks

Grouping behaviour is widespread in animals. One important reason for grouping is the reduction of individual predation risk; the larger a group, the greater the protection for the individual. Fishes, in particular, have become a model taxon in experimental research to study proximate and ultimate causes of grouping. Accordingly, numerous studies have so far demonstrated that fishes prefer to shoal with larger groups. Thus far these studies have usually examined small groups, with up to 20 individuals. However, in nature groups are often much bigger (up to several hundreds of individuals), and theory predicts that benefits, for example due to dilution effects, decline exponentially with increasing group size. Furthermore, discrimination might be absent because of limited cognitive ability. Thus, it is essential to test whether the findings from small groups also apply to large groups. Here, we examined group size preferences in the three-spined stickleback, Gasterosteus aculeatus, a small fish that forms large shoals in nature. In five experiments, subadult sticklebacks were given the choice between two shoals differing in group size (numerical contrasts: 15 versus 60, 20 versus 60, 30 versus 60, 40 versus 60 and 50 versus 60). Test fish on average preferred the larger group; this preference was stronger in the beginning of the respective trial and decreased over time. Moreover, preferences for the larger shoal decreased with decreasing group size differences, implying context-dependent preferences. We found significant discrimination up to numerical contrasts of 40:60. Our results are in accordance with the findings of shoal size discrimination in small groups and with optimality hypotheses, but might also reflect the impact of cognitive constraints.

Context-Dependent Preferences and Innovation Strategy

Disruptive innovations introduce a new performance dimension into a product category, but often suffer from inferior performance on key performance dimensions of their existing substitutes. Hence, the followers of these innovations face an important decision to make: they must choose to improve the new technology either on the key performance dimension shared with the old technology or on the new performance dimension. This paper investigates which path firms should choose when they face such a dilemma in the absence of any cost or capability issues. In doing so, we integrate customer response into the theory of technological evolution and allow preferences on the product choices to be context dependent. We show that context-dependent preferences may encourage the follower to improve the new technology on the new performance dimension. Later, we extend our game to a dynamic one and show that the context-dependent preferences may cause the pioneer to innovate less. This paper was accepted by J. Miguel Villas-Boas, marketing.

Comparative evaluations of reward dimensions in honey bees: evidence from two-alternative forced choice proboscis-extension conditioning

A major challenge in understanding choice behaviour is determining how subjects evaluate alternatives that differ along multiple dimensions. Of particular interest is whether similar dimensions are compared to each other or whether each alternative is assigned an absolute value (utility). We assumed that choice proportions would follow Weber's effect, according to which discrimination is proportional to relative difference (difference/mean). We tested honey bees in a two-alternative forced choice (2AFC) paradigm of proboscis-extension response (PER) conditioning. Subjects were conditioned over six trials to associate each of two odours with sucrose solution rewards and then tested in a choice trial between the two alternatives. Each group of subjects was tested in one treatment, and there were four treatments in each of six experiments. Rewards differed in delay, duration of feeding, and sucrose concentration. In each treatment, the high-profitability alternative was better than the low-profitability alternative along a single dimension, but between treatments of each experiment values in another dimension monotonically increased. Proboscis-response proportions during the conditioning phase tended to be greater for the high-profitability alternative, and choice proportions for it in the choice phase ranged between 0.72 and 0.89 in the 24 treatments. We show for the first time that harnessed bees are sensitive to reward delay. Preferences did not differ statistically between the different treatments of any of the experiments. The results support comparative evaluation of alternatives and are pertinent to multi-attribute choice, with implications for context-dependent preferences. We also discuss the potential advantages of the 2AFC PER simultaneous choice assay.

The Clone Effect

This paper highlights a logical contradiction in the currently accepted theory of choice. This contradiction occurs when a decision is reframed by adding a clone to the choice set. The current theory concludes that individuals have context-dependent preferences if they make consistent choices; it concludes that individuals have rational preferences if they systematically switch from one alternative to another.I argue that these are not the logical conclusions to draw from the data and that the currently accepted theory should be revised. Rational decision making assumes that individuals make consistent decisions and leads to the similarity effect. Luce’s IIA implies that adding a clone to the choice set makes an alternative more preferable, which is a framing effect.

Focus on Authors

Focus on Authors

Correlated Evolution of Positions within Mammalian cis Elements

Transcriptional regulation critically depends on proper interactions between transcription factors (TF) and their cognate DNA binding sites. The widely used model of TF-DNA binding – the Positional Weight Matrix (PWM) – presumes independence between positions within the binding site. However, there is evidence to show that the independence assumption may not always hold, and the extent of interposition dependence is not completely known. We hypothesize that the interposition dependence should partly be manifested as correlated evolution at the positions. We report a Maximum-Likelihood (ML) approach to infer correlated evolution at any two positions within a PWM, based on a multiple alignment of 5 mammalian genomes. Application to a genome-wide set of putative cis elements in human promoters reveals a prevalence of correlated evolution within cis elements. We found that the interdependence between two positions decreases with increasing distance between the positions. The interdependent positions tend to be evolutionarily more constrained and moreover, the dependence patterns are relatively similar across structurally related transcription factors. Although some of the detected mutational dependencies may be due to context-dependent genomic hyper-mutation, notably CG to TG, the majority is likely due to context-dependent preferences for specific nucleotide combinations within the cis elements. Patterns of evolution at individual nucleotide positions within mammalian TF binding sites are often significantly correlated, suggesting interposition dependence. The proposed methodology is also applicable to other classes of non-coding functional elements. A detailed investigation of mutational dependencies within specific motifs could reveal preferred nucleotide combinations that may help refine the DNA binding models.

Rationality and Context-Dependent Preferences

The standard theory of rational choice in economics considers an agent’s choices to be rational if and only if the agent makes her choices in different choice situations on the basis of a fixed preference ordering defined over the set of all possible options. This implies that a rational agent’s preferences cannot be context-dependent. This paper outlines a simple framework for defining context-dependence of preferences and for discussing relationships between context-dependent preferences and the notion of rationality.

A Range-Normalization Model of Context-Dependent Choice: A New Model and Evidence

Most utility theories of choice assume that the introduction of an irrelevant option (called the decoy) to a choice set does not change the preference between existing options. On the contrary, a wealth of behavioral data demonstrates the dependence of preference on the decoy and on the context in which the options are presented. Nevertheless, neural mechanisms underlying context-dependent preference are poorly understood. In order to shed light on these mechanisms, we design and perform a novel experiment to measure within-subject decoy effects. We find within-subject decoy effects similar to what have been shown previously with between-subject designs. More importantly, we find that not only are the decoy effects correlated, pointing to similar underlying mechanisms, but also these effects increase with the distance of the decoy from the original options. To explain these observations, we construct a plausible neuronal model that can account for decoy effects based on the trial-by-trial adjustment of neural representations to the set of available options. This adjustment mechanism, which we call range normalization, occurs when the nervous system is required to represent different stimuli distinguishably, while being limited to using bounded neural activity. The proposed model captures our experimental observations and makes new predictions about the influence of the choice set size on the decoy effects, which are in contrast to previous models of context-dependent choice preference. Critically, unlike previous psychological models, the computational resource required by our range-normalization model does not increase exponentially as the set size increases. Our results show that context-dependent choice behavior, which is commonly perceived as an irrational response to the presence of irrelevant options, could be a natural consequence of the biophysical limits of neural representation in the brain.

Lack of floral constancy by bee fly pollinators: implications for ethological isolation in an African daisy

Although divergent floral preferences of pollinating species is a likely mechanism maintaining integrity of co-occurring floral ecotypes or incipient species, reproductive isolation of floral morphs could also result from temporary floral constancy of shared pollinators. Context-dependent floral preferences have been demonstrated for many pollinating insects, suggesting that this behavior might be widespread. However, it is not yet known whether 2 plant species or morphotypes that share a single pollinator could be reproductively isolated through assortative visitation. We investigated the foraging behavior of the bee fly, Megapalpus capensis, in experimental arrays of distinct floral morphotypes of Gorteria diffusa, a South African daisy which is pollinated almost exclusively by M. capensis. Flies exhibited no intrinsic or context-dependent (according to prevailing morph) preference for floral variants nor do they display floral constancy behavior during visitation bouts. Thus, pollinator isolation through assortative visitation is an unlikely explanation for the maintenance of floral integrity across the narrow contact zones encountered in Gorteria. Despite random visitation patterns on arrays, flies exhibited different behaviors on different floral morphotypes, suggesting intrinsic responses to morphotype-specific floral cues. Our findings suggest that results of previous studies demonstrating labile preferences and constancy in insects such as bees and butterflies cannot necessarily be extrapolated to other important groups of pollinators. In pollinators, such as Megapalpus, which use flowers as arenas for multiple behaviors, including mating, and feed during long stationary bouts, learning constraints on flower handling time, the most widely accepted explanation for floral constancy, is unlikely to drive constant foraging behavior. Key words: assortative mating, Bombyliidae, floral constancy, Gorteria diffusa, pollination, reproductive isolation, South Africa, species integrity. [Behav Ecol]

Examining infants' preferences for tempo in lullabies and playsongs.

Caregivers around the world sing to their infants. Infants not only prefer to listen to infant-directed singing over adult-directed singing, but infant-directed singing also serves a function, communicating affective information to preverbal infants to aid in adjusting arousal levels. Pitch variation has previously been identified as one performance feature that may help to convey the message. Earlier research has indicated that infants' pitch preferences are context dependent, suggesting that infants are tuned in to the communicative intent of infant-directed singing. However, there are several other performance-based features present in infant-directed singing that may also contribute to the affective message. The current study examined the role of context on infants' tempo preferences in sung playsongs and lullabies. Using a head-turn preference procedure, we measured 24 preverbal infants' natural preferences for foreign language playsongs and lullabies as a function of tempo. Infants showed a preference for fast over slow tempo playsongs, but no such context dependent preference was found within lullabies. Results partially support the role of tempo as a communicative feature of infant directed singing.

Unraveling the Choice Format Effect: A Context-Dependent Random Utility Model

A few recent studies report that preferences elicited from a two-alternative choice format are different from those elicited from a three-alternative choice format, when both choice set designs contain a status quo option. We hypothesize that the choice format effect might disappear when we estimate a random utility model (RUM) that allows for context-dependent preferences. Based on the estimated context-dependent RUM, we find that the choice format effect is likely the result of two offsetting effects: a task complexity effect that increases the probability of choosing the status quo option, and a preference matching effect, which decreases the probability. <i>(JEL C25, Q51)</i>

Managing contextual preferences

To handle the overwhelming amount of information currently available, personalization systems allow users to specify through preferences which pieces of data interest them. Most often, users have different preferences depending on context. In this paper, we introduce a model for expressing such contextual preferences. Context is modeled using a set of hierarchical attributes, thus allowing context specification at various levels of detail. We formulate the context resolution problem as the problem of selecting appropriate preferences based on context for personalizing a query. We also propose algorithms for context resolution based on data structures that index preferences by exploiting the hierarchical nature of the context attributes. Finally, we evaluate our approach from two perspectives: usability and performance. Usability evaluates the overheads imposed on users for specifying context-dependent preferences, as well as their satisfaction from the quality of the results. Our performance results focus on the context resolution using the proposed indexes.

Differentiate or Imitate?: The Role of Context-Dependent Preferences

Conventional wisdom, derived from standard economic theory, is that affirm should differentiate itself from its rivals to mitigate intense price competition. Yet there are many examples of firms positioning themselves to mimic their rivals. In this paper we examine the role of context-dependent preferences in explaining this phenomenon. Behavioral researchers have long argued that consumers consider not only the absolute utility of a product but its utility relative to a reference in the choice set as well. Using this premise we construct a game theoretic model of competition between two firms. We consider two horizontally differentiated firms where some consumers own the product of one firm while the rest own the other firm's product. One firm upgrades its existing product by adding a new feature. In the absence of any cost or capability constraints, to protect its competitive position, the other firm would prefer to update its product by adding a differentiated new feature. We show that if consumers' preferences are context-dependent, then under some conditions the second mover would tend to imitate the first mover by adding the same feature even when with no cost disadvantage it can differentiate itself. This happens because context-dependent preferences cause consumers to dislike brands that are very differentiated from one another and value common features among the brands more than distinct features. As a result of this, when consumers exhibit context-dependent preferences and the proportion of second-mover's consumers who enjoy the first mover's new feature is not too small, if the second mover mimics the first mover both firms can charge higher prices for their upgraded products. This outcome, in turn, leads the first mover to pick a new feature to upgrade its existing product such that it would encourage the second mover to imitate itself. Therefore, unlike the extant literature, our analysis shows that mimicking/co-location does not necessarily require a tradeoff between higher demand and lower prices.

Differentiate or Imitate? The Role of Context-Dependent Preferences

Laboratory and field experiments show that when choosing among a set of objects, consumers could be subjected to context-dependent preferences and evaluate options by considering both the absolute utilities and their relative standing in the choice set. Using this premise we construct a game-theoretic model of competition between two firms and investigate how a firm's decision to differentiate or imitate is affected when consumers' preferences are context-dependent. We consider two horizontally differentiated firms where some consumers own the product of one firm and the rest own the other firm's product. One firm upgrades its existing product by adding a new feature. In the absence of any cost or capability constraints, to protect its competitive position, the other firm would prefer to upgrade its product by adding a differentiated new feature. We show that if consumers' preferences are context-dependent and the new feature is of an incremental type, the second mover prefers to imitate the first mover by adding the same feature even when there is no cost disadvantage to differentiate itself. This happens because context-dependent preferences cause consumers to dislike brands that are very differentiated from one another. Thus, if the second mover mimics the first mover, both firms can charge higher prices for their upgraded products (i.e., imitation leads to higher prices). This outcome, in turn, leads the first mover to pick a new feature such that it would induce the second mover to imitate. Therefore, our analysis shows that the need for context management leads not just to imitation but also to accommodating imitation.

Uncertainty, loss aversion, and markets for energy efficiency

Increasing energy efficiency is critical to mitigating greenhouse gas emissions from fossil-fuel combustion, reducing oil dependence, and achieving a sustainable global energy system. The tendency of markets to neglect apparently cost-effective energy efficiency options has been called the “efficiency gap” or “energy paradox.” The market for energy efficiency in new, energy-using durable goods, however, appears to have a bias that leads to undervaluation of future energy savings relative to their expected value. This paper argues that the bias is chiefly produced by the combination of substantial uncertainty about the net value of future fuel savings and the loss aversion of typical consumers. This framework relies on the theory of context-dependent preferences. The uncertainty-loss aversion bias against energy efficiency is quantifiable, making it potentially correctible by policy measures. The welfare economics of such policies remains unresolved. Data on the costs of increased fuel economy of new passenger cars, taken from a National Research Council study, illustrate how an apparently cost-effective increase in energy efficiency would be uninteresting to loss-averse consumers.