High-quality Reward Research Articles

Metacognition in wild Japanese macaques: cost and stakes influencing information-seeking behavior

Metacognition allows us to evaluate memories and knowledge, thus enabling us to distinguish between what we know and what we do not. Studies have shown that species other than humans may possess similar abilities. However, the number of species tested was limited. Testing ten free-ranging Japanese macaques (Macaca fuscata) on a task in which they had to find food hidden inside one of the four opaque tubes, we investigated whether these subjects would seek information when needed. The monkeys could look inside the tubes before selecting one. We varied three parameters: the baiting process, the cost that monkeys had to pay to look inside the tubes, and the reward at stake. We assessed whether and how these parameters would affect the monkeys’ tendency to look inside the tube before selecting one. When they were not shown which tube contained the reward, nine monkeys looked significantly more frequently in at least one condition. Half of them tended to reduce their looks when the cost was high, but only when they already knew the location of the reward. When a high-quality reward was at stake, four monkeys tended to look more inside the tubes, even though they already knew the reward’s location. Our results are consistent with those of rhesus macaques, suggesting that metacognitive-like abilities may be shared by Cercopithecidae, and that, at least some monkeys may be aware of their lack of knowledge.

Past experience with spatial or temporal resource unpredictability shapes exploration in honey bees, Apis mellifera

Foraging animals must repeatedly decide whether to exploit current resources or explore to gain information and locate new resources. Balancing these two often mutually exclusive options is made more difficult by environmental changes that can occur predictably, as seen in daily patterns of nectar secretion in flowers, or unpredictably, as seen when resources are depleted by competitors. Recent experiences with predictable and unpredictable rewards potentially provide information that foraging animals can use to decide when it is beneficial to explore versus exploit. However, it is unclear how the predictability of recent experiences can shape an animal's future exploration after rewards vanish and they have no option but to search. We tested how experience with unpredictability related to two types of environmental change, unpredictability in reward location and unpredictability in daily timing of rewards, shaped the exploratory behaviour of honey bees in the absence of a reward. We found that honey bees that experienced unpredictable rewards in space or time were less precise in their exploration after those rewards vanished. In spatial experiments, bees searched more broadly within a patch if they had experience with unpredictably located rewards and spent more time searching outside the patch than bees that experienced predictably located rewards. In temporal experiments, bees that experienced unpredictably timed rewards distributed their search effort more broadly outside of the time they last received a high-quality reward; also, bees that experienced any change in reward searched more intensively regardless of how predictable the reward had been. In contrast to the differences in search precision, a bee's previous experience with spatial or temporal unpredictability of rewards did not change how persistently she searched for a reward. This study provides novel insights into how predictability of previous experiences can shape exploratory behaviour even in the absence of rewards. • Recent experience can inform honey bees' exploratory behaviour when rewards vanish. • Spatial or temporal reward unpredictability made honey bees search less precisely. • Bees searched more broadly within and outside a patch after unpredictable rewards. • Honey bees searched more intensively after experiencing temporally changing rewards. • Experience with unpredictability did not influence honey bee search persistence.

Horses wait for more and better rewards in a delay of gratification paradigm.

Self-control, defined as the ability to forgo immediate satisfaction in favor of better pay-offs in the future, has been extensively studied, revealing enormous variation between and within species. Horses are interesting in this regard because as a grazing species they are expected to show low self-control whereas its social complexity might be linked to high self-control abilities. Additionally, self-control may be a key factor in training and/or coping with potentially stressful husbandry conditions. We assessed horses’ self-control abilities in a simplified delay of gratification test that can be easily implemented in a farm setting. In Experiment 1, we gave horses (N = 52) the choice between an immediately available low-quality reward and a delayed high-quality reward that could only be obtained if the horse refrained from consuming the immediate reward. Different experimenters (N = 30) that underwent prior training in the procedures, tested horses in two test phases either with their eyes visible or invisible (sunglasses). Twenty horses waited up to the maximum delay stage of 60 s while all horses performed worse in the second test phase. In Experiment 2, we improved the test procedure (i.e., one experimenter, refined criterion for success), and tested 30 additional horses in a quality and quantity condition (one reward vs. delayed bigger reward). Two horses successfully waited for 60 s (quality: N = 1, quantity: N = 1). Horses tolerated higher delays, if they were first tested in the quantity condition. Furthermore, horses that were fed hay ad libitum, instead of in a restricted manner, reached higher delays. Coping behaviors (e.g., looking away, head movements, pawing, and increasing distance to reward) facilitated waiting success and horses were able to anticipate the upcoming delay duration as indicated by non-random distributions of giving-up times. We found no correlations between owner-assessed traits (e.g., trainability and patience) and individual performance in the test. These results suggest that horses are able to exert self-control in a delay of gratification paradigm similar to other domesticated species. Our simplified paradigm could be used to gather large scale data, e.g., to investigate the role of self-control in trainability or success in equestrian sports.

Intra- and interspecific variation in self-control capacities of parrots in a delay of gratification task

Forgoing immediate satisfaction for higher pay-offs in the future (delayed gratification) could be adaptive in situations that wild animals may encounter. To explain species-differences in self-control, hypotheses based on social complexity, feeding ecology, brain size and metabolic rate have been proposed. To explore these hypotheses in a comparative setting, we tested three macaw species (neotropical parrots)—great green macaws (N = 8), blue-throated macaws (N = 6), blue-headed macaws (N = 6)—and the distantly related African grey parrots (afrotropical parrots; N = 8) in a modified rotating tray task, in which subjects are required to inhibit consuming a constantly available low-quality reward in favour of a high-quality reward that becomes available only after an increasing delay (min. 5 s, max. 60 s). All four species successfully waited for a minimum of 8.3 s ± 11.7 s (group level mean ± SD) with African greys reaching a delay of 29.4 ± 15.2 s, and great green macaws—as best performing macaw species—tolerating delays of 20 s ± 8 s. The best performing African grey individual reached a maximum delay of 50 s, whereas, a great green and a blue-throated macaw tolerated a delay of 30 s max. Females tolerated higher maximum delays than males. Engaging in distraction behaviours enhanced waiting performance across species and all birds were able to anticipate the waiting duration. Our results suggest that both feeding and socio-ecological complexity may be a factor in self-control, but further systematically collected comparative data on self-control of different (parrot) species are required to test the evolutionary hypotheses rigorously.

An exploration of the relationship between recruitment communication and foraging in stingless bees.

Social information is widely used in the animal kingdom and can be highly adaptive. In social insects, foragers can use social information to find food, avoid danger, or choose a new nest site. Copying others allows individuals to obtain information without having to sample the environment. When foragers communicate information they will often only advertise high-quality food sources, thereby filtering out less adaptive information. Stingless bees, a large pantropical group of highly eusocial bees, face intense inter- and intra-specific competition for limited resources, yet display disparate foraging strategies. Within the same environment there are species that communicate the location of food resources to nest-mates and species that do not. Our current understanding of why some species communicate foraging sites while others do not is limited. Studying freely foraging colonies of several co-existing stingless bee species in Brazil, we investigated if recruitment to specific food locations is linked to 1) the sugar content of forage, 2) the duration of foraging trips, and 3) the variation in activity of a colony from 1 day to another and the variation in activity in a species over a day. We found that, contrary to our expectations, species with recruitment communication did not return with higher quality forage than species that do not recruit nestmates. Furthermore, foragers from recruiting species did not have shorter foraging trip durations than those from weakly recruiting species. Given the intense inter- and intraspecific competition for resources in these environments, it may be that recruiting species favor food resources that can be monopolized by the colony rather than food sources that offer high-quality rewards.

Dogs wait longer for better rewards than wolves in a delay of gratification task: but why?

Self-control has been shown to be linked with being cooperative and successful in humans and with the g-factor in chimpanzees. As such, it is likely to play an important role in all forms of problem-solving. Self-control, however, does not just vary across individuals but seems also to be dependent on the ecological niche of the respective species. With dogs having been selected to live in the human environment, several domestication hypotheses have predicted that dogs are better at self-control and thus more tolerant of longer delays than wolves. Here we set out to test this prediction by comparing dogs’ and wolves’ self-control abilities using a delay of gratification task where the animals had to wait for a predefined delay duration to exchange a low-quality reward for a high-quality reward. We found that in our task, dogs outperformed the wolves waiting an average of 66 s vs. 24 s in the wolves. Food quality did not influence how long the animals waited for the better reward. However, dogs performed overall better in motivation trials than the wolves, although the dogs’ performance in those trials was dependent on the duration of the delays in the test trials, whereas this was not the case for the wolves. Overall, the data suggest that selection by humans for traits influencing self-control rather than ecological factors might drive self-control abilities in wolves and dogs. However, several other factors might contribute or explain the observed differences including the presence of the humans, which might have inhibited the dogs more than the wolves, lower motivation of the wolves compared to the dogs to participate in the task and/or wolves having a better understanding of the task contingencies. These possible explanations need further exploration.

Learning how to price intelligently on a reward-based crowdfunding platform

Purpose This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting-edge research and case studies. Design/methodology/approach This briefing is prepared by an independent writer who adds their own impartial comments and places the articles in context. Findings This research paper concentrates on determining the optimal pricing strategy for a reward-based crowdfunding project. In most market scenarios an early-bird pricing strategy using only high quality rewards was found to be the optimal strategy for maximizing revenue and minimizing product development costs, in comparison with a versioning pricing strategy. A reasonable project funding goal figure should also be selected to avoid the project failing to reach its all-or-nothing target. Originality/value The briefing saves busy executives, strategists and researchers hours of reading time by selecting only the very best, most pertinent information and presenting it in a condensed and easy-to-digest format.

Parrots do not show inequity aversion

Inequity aversion, the negative reaction to unequal treatment, is considered a mechanism for stabilizing cooperative interactions between non-kin group members. However, this might only be adaptive for species that switch cooperative partners. Utilizing a comparative approach, inequity aversion has been assessed in many mammalian species and recently also in corvids and one parrot species, kea, revealing mixed results. To broaden our knowledge about the phylogenetic distribution of inequity aversion, we tested four parrot species in the token exchange paradigm. We varied the quality of rewards delivered to dyads of birds, as well as the effort required to obtain a reward. Blue-headed macaws and African grey parrots showed no reaction to being rewarded unequally. The bigger macaws were less willing to exchange tokens in the “unequal” condition compared to the “equal high” condition in which both birds obtained high quality rewards, but a closer examination of the results and the findings from the control conditions reveal that inequity aversion does not account for it. None of the species responded to inequity in terms of effort. Parrots may not exhibit inequity aversion due to interdependence on their life-long partner and the high costs associated with finding a new partner.

Early bird or versioning

PurposeCrowdfunding, especially reward-based crowdfunding, has quickly evolved into a commonly used vehicle for innovating entrepreneurs to develop their products. Many crowdfunding platforms allow creators maximum flexibility in terms of the prices and rewards offered in a project to gain sufficient capital. However, creators need to understand how to design project rewards and how to select a pricing strategy, in addition to whether the creator should spend resources on designing multiple rewards of varying quality. The purpose of this paper is to address these issues by answering whether and why there are significant differences in the application of early-bird and versioning pricing strategies in crowdfunding.Design/methodology/approachThis paper develops a two-stage dynamic game model with incomplete information, proposes a corollary calculated by analyzing a perfect Bayesian equilibrium, and then tests Corollary 1 by empirical analysis.FindingsContrary to the findings of other studies, the results show that an early-bird pricing strategy is likely better than a versioning pricing strategy for earning greater revenue in a crowdfunding context, on average. This finding means that creators do not have to spend as much in designing rewards of various qualities; rather, they should only provide multiple price options for high-quality rewards. However, if the heterogeneity of target backers’ valuations and the quality difference between two types of products are adequately high, a versioning pricing strategy may be a good choice for creators.Practical implicationsThis paper provides a reference for creators regarding the selection of pricing strategies and the design of reward quality when launching crowdfunding projects.Originality/valueThis paper explains an interesting and practical issue in the design of reward quality and the selection of a pricing strategy after fully considering the role of the crowdfunding all-or-nothing mechanism and special backer behavior.

Orangutans (Pongo abelii) make flexible decisions relative to reward quality and tool functionality in a multi-dimensional tool-use task.

Making economic decisions in a natural foraging situation that involves the use of tools may require an animal to consider more levels of relational complexity than merely deciding between an immediate and a delayed food option. We used the same method previously used with Goffin´s cockatoos to investigate the orangutans’ flexibility for making the most profitable decisions when confronted with five different settings that included one or two different apparatuses, two different tools and two food items (one more preferred than the other). We found that orangutans made profitable decisions relative to reward quality, when the task required the subjects to select a tool over an immediately accessible food reward. Furthermore, most subjects were sensitive to work-effort when the immediate and the delayed option (directly accessible by using a tool) led to the same outcome. Most subjects continued to make profitable decisions that required taking into account the tool functionality. In a final multidimensional task design in which subjects had to simultaneously focus on two apparatuses, two reward qualities and two different tools, the orangutans chose the functional tool to access the high quality reward.

Do dogs experience frustration? New contributions on successive negative contrast in domestic dogs (Canis familiaris)

An unexpected change in reward quantity or quality frequently elicits a sharp decrease of responses as well as a negative emotional state. This phenomenon is called successive negative contrast (SNC) and, although it has been observed in numerous mammals, results in dogs have been inconsistent. The aim of this study was to evaluate SNC in dogs, comparing the effects of rewards of different qualities in a non-social task carried out in the dogs’ usual environment. Dogs were separated into two experimental groups that experienced a downshift from a high quality reward (liver or sausage) to a low quality one (dry food), as well as a control group that always received dry food. The task involved a dog toy with bone shaped pieces that had to be removed to get the food hidden underneath. When the reward changed from liver to dry food, dogs picked up significantly fewer bones than the control group. However, this effect was not observed with sausage. Results show SNC in dogs in a non-social task carried out in their home environment. Additionally, the importance of the discrepancy in the hedonic value of the rewards is highlighted.

Individual ant workers show self-control.

Often, the first option is not the best. Self-control can allow humans and animals to improve resource intake under such conditions. Self-control in animals is often investigated using intertemporal choice tasks-choosing a smaller reward immediately or a larger reward after a delay. However, intertemporal choice tasks may underestimate self-control, as test subjects may not fully understand the task. Vertebrates show much greater apparent self-control in more natural foraging contexts and spatial discounting tasks than in intertemporal choice tasks. However, little is still known about self-control in invertebrates. Here, we investigate self-control in the black garden ant Lasius niger We confront individual workers with a spatial discounting task, offering a high-quality reward far from the nest and a poor-quality reward closer to the nest. Most ants (69%) successfully ignored the closer, poorer reward in favour of the further, better one. However, when both the far and the close rewards were of the same quality, most ants (83%) chose the closer feeder, indicating that the ants were indeed exercising self-control, as opposed to a fixation on an already known food source.

Tolerance to delayed reward tasks in social and non-social contexts

Domestic dogs have demonstrated striking social skills towards humans, however, there are few studies investigating impulsivity with delay-choice tasks in communicative contexts. In Study 1 we introduced a novel social delay-choice task in which subjects had to choose between one human cueing an immediate, low quality reward and another human signaling a delayed, high quality reward. In Study 2 we evaluated the tolerance to increasing delays using social and non-social cues. We also explored if more self-controlled dogs show any distinct behaviours during delays. Finally, we correlated all results with the Dog Impulsivity Assessment Scale (Wright et al., 2011). In Study 1 dogs reached an average maximum delay of 11.55s. In Study 2 that average was 52.14s with social cues and 40.2s with non-social, but differences were not significant. Tolerance to delays showed high interindividual variation. Dogs remained mostly standing and near the delayed experimenter in the social tasks although we could not to find any distinct coping strategies. No significant correlations were found between the delay reached and behaviours, neither with the scale. These results show the relevance of the parameters and methods used to investigate tolerance to delay of reinforcements. More investigations are required, especially an assessment of the same subjects performing the same tasks using different contexts.

The influence of past experience with flower reward quality on social learning in bumblebees

Foraging decisions can be influenced by innate biases, previous individual experience and social information acquired from conspecifics. We examined how these factors interact to affect flower colour preference in the large earth bumblebee, Bombus terrestris dalmatinus. Individual bees with no experience foraging on coloured flowers were first tested for innate colour biases on an unrewarded array of blue and yellow artificial flowers. Depending on treatment, bees then acquired individual experience foraging on a colour (either blue or yellow) associated with high-quality sucrose rewards, or a colour with low-quality sucrose rewards, or they did not acquire any individual experience. Bees were then exposed to the alternative colour associated with conspecific demonstrator bees (social information) or the alternative colour with no social information. Bees that had no individual experience visited flower colours that were associated with conspecific demonstrators (social information) but only significantly if the socially demonstrated colour was one for which bees had an innate bias. When bees had individual experience foraging on a colour with high-quality rewards they continued foraging on that colour, and generally did not visit the socially demonstrated alternative colour, regardless of innate colour bias. Alternatively, when bees had individual experience foraging on colours with low-quality rewards, they made more visits to the socially demonstrated alternative flower colour, but only when the alternative colour was the colour for which they had an innate bias. Bees that had no access to social information continued to forage on low-reward coloured flowers. Thus we show that reward quality of resources with which bees have individual experience affects the use of social information but with an important role of innate biases.

Incentive Relativity and the Specificity of Reward Expectations in Honey Bees

Honey bees were trained in a proboscis extension response procedure on a high quality reward to one of two odors under one of two contexts and then on a lower quality reward under the alternative context to the alternative odor. The performance decrement induced by the reduced reward, revealed by comparisons with subjects trained continually on the lower reward, was independent of odor context combinations or the order of experience with stimuli. In a second experiment subjects were forward or backward conditioned to a high quality reward or fed unconditionally and then trained ona low reward in a novel context to a novel odor. The observed performance decrement depended only on exposure to the high quality reward. These results suggest that incentive contrast effects arise from a simple mechanism—the comparison of a current incentive with experienced incentives— that is effectively independent of cues that signal a reward.

Extinction in a straight alley as a function of varied quality and quantity of reward sequence

Six groups of albino rats were extinguished in a straight alley after receiving two daily trials an one of the following varied quality and/or quantity of reward sequences: 1 regular pellet followed by 1 regular pellet, 1 regular pellet followed by 1 sucrose pellet, 1 sucrose pellet followed by 1 regular pellet, 1 regular pellet followed by 16 sucrose pellets, 1 sucrose pellet followed by 16 sucrose pellets, and 16 sucrose pellets followed by 1 sucrose pellet. Further evidence for an extension of the sequential hypothesis to include quality of reward was provided by showing that greater resistance to extinction results when a high-quality reward follows a low-quality reward than when the opposite sequence occurs. In addition, variations in both quantity and quality of reward produced more resistance to extinction than variations in quantity of reward alone.

Extinction as a function of varied quality and quantity of reward sequence in a straight alley

Four groups of male albino rats were extinguished in a straight alley after receiving two daily trials on one of the following varied quality and/or quantity of reward sequences: 1 alfalfa pellet followed by 1 sucrose pellet, 1 sucrose pellet followed by 1 alfalfa pellet, a single alfalfa pellet followed by 16 sucrose pellets, and a single sucrose pellet followed by 16 sucrose pellets. The results indicated that a high-quality reward following a low-quality reward produced greater resistance to extinction than when a low-quality reward followed a high-quality reward. The findings were interpreted within Capaldi’s sequential theory.