The Aggregated Extremes Effect: Not All Routes to “Balanced” Bundles are Equally Appealing

Prior research establishes that consumers are averse to extreme options, but what does a “moderate” option look like in the context of choices among bundles of items, such as investment portfolios or product assortment packs? We propose that for bundles, two paths to creating risk and reward balance exist: a “bundle‐of‐pure‐moderation” with all moderate‐risk–moderate‐reward (moderate RR) components and a “bundle‐of‐extremes,” composed of equal numbers of extreme high‐risk–high‐reward (high RR) and low‐risk–low‐reward (low RR) components. We show that consumers have stronger preference for the balanced bundle when composed of a bundle‐of‐extremes rather than a bundle‐of‐pure‐moderation, even when equated on expected value, a phenomenon we term “the aggregated extremes effect.” This effect occurs across different choice set configurations and across multiple domains. Additionally, this effect is eliminated among consumers who view the high RR and low RR components as incompatible, as this undermines the perceived attractiveness of the bundle‐of‐extremes. Finally, this effect is also eliminated by exposing consumers to a depiction of potential outcomes, such that consumers can better perceive the risk reduction upside of a bundle‐of‐pure‐moderation.     

对整合模型和占优启发式模型的检验：基于信息加工过程的眼动研究证据

基于信息加工过程视角, 本研究采用眼动技术检验风险决策整合模型和占优启发式模型。结果表明, 自主决策任务条件下决策过程反应时及信息搜索模式均不同于期望价值(EV)迫选任务条件下的决策过程反应时及信息搜索模式; 自主决策任务条件下决策过程反应时并未随着选项间整体值(CPT值)差值的变大而变快, 且基于特征(attribute-based)的信息搜索多于基于选项(option-based)的信息搜索, 不符合整合模型预期。此外, 决策者亦未按照占优启发式模型所假定的决策步骤进行决策。基于信息加工过程的检验结果既不利于以累积预期理论为代表的整合模型, 亦不利于占优启发式模型。文章建议从决策过程视角检验已有决策模型及建立新的启发式决策过程模型(process model)。     

Waiting by mistake: Symbolic representation of rewards modulates intertemporal choice in capuchin monkeys,preschool children and adult humans

In the Delay choice task subjects choose between a smaller immediate option and a larger delayed option. This paradigm, also known as intertemporal choice task, is frequently used to assess delay tolerance, interpreting a preference for the larger delayed option as willingness to wait. However, in the Delay choice task subjects face a dilemma between two preferred responses: “go for more” (i.e., selecting the larger, but delayed, option) vs. “go for sooner” (i.e., selecting the immediate, but smaller, option). When the options consist of visible food amounts, at least some of the choices of the larger delayed option might be due to a failure to inhibit a prepotent response towards the larger option rather than to a sustained delay tolerance. To disentangle this issue, we tested 10 capuchin monkeys, 101 preschool children, and 88 adult humans in a Delay choice task with food, low-symbolic tokens (objects that can be exchanged with food and have a one-to-one correspondence with food items), and high-symbolic tokens (objects that can be exchanged with food and have a one-to-many correspondence with food items). This allows evaluating how different methods of representing rewards modulate the relative contribution of the “go for more” and “go for sooner” responses. Consistently with the idea that choices for the delayed option are sometimes due to a failure at inhibiting the prepotent response for the larger quantity, we expected high-symbolic tokens to decrease the salience of the larger option, thus reducing “go for more” responses. In fact, previous findings have shown that inhibiting prepotent responses for quantity is easier when the problem is framed in a symbolic context. Overall, opting for the larger delayed option in the visible-food version of the Delay choice task seems to partially result from an impulsive preference for quantity, rather than from a sustained delay tolerance. In capuchins and children high-symbolic stimuli decreased the individual’s preference for the larger reward by distancing from its appetitive features. Conversely, the sophisticated symbolic skills of adult humans prevented the distancing effect of high-symbolic stimuli in this population, although this result may be due to methodological differences between adult humans and the other two populations under study. Our data extend the knowledge concerning the influence of symbols on both human and non-human primate behavior and add a new element to the interpretation of the Delay choice task. Since high-symbolic stimuli decrease the individual’s preference for the larger reward by eliminating those choices due to prepotent responses towards the larger quantity, they allow to better discriminate responses based on genuine delay aversion. Thus, these findings invite greater caution in interpreting the results obtained with the visible-food version of the Delay choice task, which may overestimate delay tolerance.     

Thinking about others and the future: Neural correlates of perspective taking relate to preferences for delayed rewards

We infer the thoughts and feelings of others by taking their perspectives. Similar processes could be used to understand how we will be affected by future events, by allowing us to take the perspective of our future self. In this paper, we test this idea using a previously presented framework for guiding predictions. The framework proposes that a shared neural mechanism is involved in controlling egocentric bias, both while shifting our perspective away from self and towards others, and while shifting our perspective from immediate to future perspectives. To test this framework, 36 adults performed an intertemporal choice task. They were then scanned using 3T functional magnetic resonance imaging while completing a false-belief “localizer” task, which requires egocentric bias control. A positive correlation was observed between the right temporoparietal junction (rTPJ) response during the false-belief task, and preferences for delayed rewards in intertemporal choices. A subset of participants performed the intertemporal choice task again in the scanner, which revealed that the response of the same rTPJ cluster, individually localized during the false-belief task, was higher during delayed over immediate reward choices. In addition, functional connectivity between the rTPJ and ventromedial prefrontal cortex was found to differ between immediate and delayed choices. The current results indicate an overlap in processes of egocentric bias control and those that determine preferences in intertemporal choices, offering a social cognitive explanation for why rewards are devalued with delay in temporal discounting.     

Stochastic transitivity and the unidimensional control of choice

A concurrent-chains paradigm was used to test three models of preference for schedules of reinforcement. Each model assumes choice to be a monotonic function of values on a single dimension (“simple scalability”). For choices involving variable-interval and fixed-interval schedules, this dimension is assumed to be an harmonic average of the interreinforcement intervals; for choices involving fixedinterval and fixed-ratio schedules, the dimension is the time to reinforcement irrespective of response rate; for choices involving different combinations of rate and duration of reinforcement, the dimension is the rate of “reinforcement-time”, or the product of the two parameters. Each model implies a strong form of transitivity (“functional equivalence”), which held for half the subjects (that half exclusively sensitive to the reinforcement variable specified by the model). An alternative unidimensional model which implies a weaker form of transitivity (“weak binary utility model”) was consistent with the preferences of all subjects. This model states that a single factor controls the direction of preferences but not necessarily the exact choice probability, as simple scalability assumes.     

Tests of an indifference rule in variable‐delay and double‐reward choice procedures with humans

Four hundred and fifty participants were recruited from Amazon Mechanical Turk across 3 experiments to test the predictions of a hyperbolic discounting equation in accounting for human choices involving variable delays or multiple rewards (Mazur, 1984, 1986). In Experiment 1, participants made hypothetical choices between 2 monetary alternatives, 1 consisting of a fixed delay and another consisting of 2 delays of equal probability (i.e., a variable‐delay procedure). In Experiment 2, participants made hypothetical monetary choices between a single, immediate reward and 2 rewards, 1 immediate and 1 delayed (i.e., a double‐reward procedure). Experiment 3 also used a double‐reward procedure, but with 2 delayed rewards. Participants in all 3 experiments also completed a standard delay‐discounting task. Finally, 3 reward amounts were tested in each type of task ($100, $1000, and $5000). In the double‐reward conditions (Experiments 2 and 3), the results were in good qualitative and quantitative agreement with Mazur's model (1984, 1986). In contrast, when participants made choices involving variable delays (Experiment 1), there was relatively poor qualitative and quantitative agreement with this model. These results, along with our previous findings, suggest the structure of questions in hypothetical tasks with humans can be a strong determinant of the choice pattern.     

Do humans produce the speed–accuracy trade-off that maximizes reward rate?

In this paper we investigate trade-offs between speed and accuracy that are produced by humans when confronted with a sequence of choices between two alternatives. We assume that the choice process is described by the drift diffusion model, in which the speed–accuracy trade-off is primarily controlled by the value of the decision threshold. We test the hypothesis that participants choose the decision threshold that maximizes reward rate, defined as an average number of rewards per unit of time. In particular, we test four predictions derived on the basis of this hypothesis in two behavioural experiments. The data from all participants of our experiments provide support only for some of the predictions, and on average the participants are slower and more accurate than predicted by reward rate maximization. However, when we limit our analysis to subgroups of 30–50% of participants who earned the highest overall rewards, all the predictions are satisfied by the data. This suggests that a substantial subset of participants do select decision thresholds that maximize reward rate. We also discuss possible reasons why the remaining participants select thresholds higher than optimal, including the possibility that participants optimize a combination of reward rate and accuracy or that they compensate for the influence of timing uncertainty, or both.     

Simple matrix methods for analyzing diffusion models of choice probability, choice response time, and simple response time

Diffusion processes (e.g., Wiener process, Ornstein-Uhlenbeck process) are powerful approaches to model human information processes in a variety of psychological tasks. Lack of mathematical tractability, however, has prevented broad applications of these models to empirical data. This tutorial explains step by step, using a matrix approach, how to construct these models, how to implement them on a computer, and how to calculate the predictions made by these models. In particular, we present models for binaries choices for unidimensional and multiattribute choice alternatives; for simple reaction time tasks; and for three alternatives choice problems.     

The similarity heuristic

Decision makers often make snap judgments using fast‐and‐frugal decision rules called cognitive heuristics. Research into cognitive heuristics has been divided into two camps. One camp has emphasized the limitations and biases produced by the heuristics; another has focused on the accuracy of heuristics and their ecological validity. In this paper we investigate a heuristic proposed by the first camp, using the methods of the second. We investigate a subset of the representativeness heuristic we call the “similarity” heuristic, whereby decision makers who use it judge the likelihood that an instance is a member of one category rather than another by the degree to which it is similar to others in that category. We provide a mathematical model of the heuristic and test it experimentally in a trinomial environment. In this environment, the similarity heuristic turns out to be a reliable and accurate choice rule and both choice and response time data suggest it is also how choices are made. We conclude with a theoretical discussion of how our work fits in the broader “fast‐and‐frugal” heuristics program, and of the boundary conditions for the similarity heuristic. Copyright © 2009 John Wiley & Sons, Ltd.     

Discrete dynamic choice: An extension of the choice models of thurstone and luce

The present paper deals with the extension of two well-known static discrete choice theories to the dynamic situation in which individuals make choices at several points in (continuous) time. A dynamic version of Luce's Axiom, “independence from irrelevant alternatives”, is proposed and some of its implications are derived. In the static case Yellott (J. Math. Psych. 1977, 15, 109–146) and others have demonstrated that an independent random utility model generated from the extreme value distribution exp(?e^?ax?b) becomes equivalent to Luce's Axiom. Yellott also introduced an axiom called “invariance under uniform expansions of the choice set”, and he proved that within the class of random utility models with independent identically distributed utilities (apart from a location shift) this axiom is equivalent to Luce's Axiom. These results are extended to the dynamic situation and it is shown that if the utility processes are expressed by so-called extremal processes the corresponding choice model is Markovian. A nonstationary generalization is proposed which is a substantial interest in applications where the parameters of the choice process are influenced by previous choice experience or by time-varying exogenous variables. In particular, it is demonstrated that the nonstationary model is Markovian if and only if the joint choice probabilities at two points in time have a particular form. Thus, the paper provides a rationale for applying a specific class of Markov models as the point of departure when modelling mobility processes that involve individual discrete decisions over time.     

社交媒体分享线索如何影响消费者的选择：印象管理与自主感缺失

随着社交媒体, 第三方消费点评网站及各类电商平台的蓬勃发展, 消费者能够越来越容易地与他人分享自己的消费和体验。为了适应这一迅猛的发展势头, 企业采取一系列措施加入社交媒体营销刺激消费者分享。如在产品界面添加分享按钮, 在各大社交平台添加主题标签, 或者直接使用带有分享刺激的广告口号。与以往研究关注消费者决策后的分享行为不同, 本研究提出社交媒体分享线索在消费者决策中发挥着重要作用, 影响消费者的判断与选择。具体来说, 本项目认为社交媒体分享线索一方面激发了消费者的印象管理动机, 另一方面也降低了自主感, 在此基础上探究了的两个行为决策结果：产品兴趣和决策终止。本项目具有重要的理论意义, 突破前人研究大多关注决策后分享的局限, 对现有社交媒体分享, 及数字环境如何影响消费行为是有益的补充。在实践上, 对企业如何更好地开展社会化媒体营销有着重要的指导意义。     

Measuring the Evolution of Radical Right-Wing Posting Behaviors Online

ABSTRACT

Researchers have previously explored how right-wing extremists build a collective identity online by targeting their perceived “threat,” but little is known about how this “us” versus “them” dynamic evolves over time. This study uses a sentiment analysis-based algorithm that adapts criminal career measures, as well as semi-parametric group-based modeling, to evaluate how users’ anti-Semitic, anti-Black, and anti-LGBTQ posting behaviors develop on a sub-forum of the most conspicuous white supremacy forum. The results highlight the extent to which authors target their key adversaries over time, as well as the applicability of a criminal career approach in measuring radical posting trajectories online.     

A Model of Financial Incentive Effects in Decision Making

This paper proposes a model of the mediating processes whereby performance-contingent financial incentives influence decision quality and provides empirical evidence relevant to assessing the model. We hypothesize that performance-contingent incentives impact both cognitions and emotions, and that these cognitive and affective changes mediate the relationship between incentives and decision quality. To test these hypotheses, 84 undergraduate students were randomly assigned to conditions in which financial incentives were either performance contingent or randomly distributed. Participants used software that collected data on their information processing behavior to make choices from multiattribute choice information displays. After completing their choices, participants′ level of negative affect was assessed. Consistent with the predictions of the model, participants offered performance-contingent incentives took longer to choose, examined more information, had higher levels of negative affect, and used decision strategies that led to more accurate choices than participants offered randomly distributed incentives. Path analyses using structural equations modeling indicated that the changes in information processing behavior induced by financial incentives increased decision quality, while the increased levels of negative affect associated with incentives decreased decision quality. The paper concludes that identifying and measuring mediating variables is an important component of a research agenda designed to generate predictive theory of the relationship between financial incentives and decision quality.     

When, what, and how much to reward in reinforcement learning-based models of cognition

Reinforcement learning approaches to cognitive modeling represent task acquisition as learning to choose the sequence of steps that accomplishes the task while maximizing a reward. However, an apparently unrecognized problem for modelers is choosing when, what, and how much to reward; that is, when (the moment: end of trial, subtask, or some other interval of task performance), what (the objective function: e.g., performance time or performance accuracy), and how much (the magnitude: with binary, categorical, or continuous values). In this article, we explore the problem space of these three parameters in the context of a task whose completion entails some combination of 36 state-action pairs, where all intermediate states (i.e., after the initial state and prior to the end state) represent progressive but partial completion of the task. Different choices produce profoundly different learning paths and outcomes, with the strongest effect for moment. Unfortunately, there is little discussion in the literature of the effect of such choices. This absence is disappointing, as the choice of when, what, and how much needs to be made by a modeler for every learning model.     

适应性时间管理：死亡意识对时间知觉和跨期决策的影响

死亡意识是个体对自身死亡必然性的认识; 基于进化适应性的考量, 作者认为具有前瞻性的死亡意识作为人类特有的认知能力和个体生命史的终极坐标, 不仅可能引起恐惧感和防御反应, 更重要的是可以帮助人们做出适应性的时间管理。据此推论, 死亡意识的启动会加强人们对时间有限性的关注, 体验出更强的时间流逝感, 影响人们对时间的评估, 以及人们对不同时间点的成本与收益进行权衡而做出的跨期决策。本研究采用死亡凸显范式启动死亡意识, 通过两个实验探讨了死亡意识、时间知觉和跨期决策三者之间的关系。结果发现, 死亡意识启动使被试低估时间距离, 并表现出较低的跨期决策延迟折扣率, 从而在较小的即时获益与更大的延迟的获益之间更为偏好未来导向的选项。进一步的分析显示, 时间知觉在死亡意识和跨期决策延迟折扣率之间起到部分中介变量的作用。以上的研究结果初步揭示了死亡意识在时间管理上的适应性价值。     

Building blocks of self-control: increased tolerance for delay with bundled rewards

Impulsive choice can be defined as temporary preference for a smaller-sooner reward (SS) over a larger-later reward (LL). Hyperbolic discounting implies that impulsive choices will occur less when organisms choose between a series of SSs versus LLs all at once than when they choose between single SS versus LL pairs. Eight rats were exposed to two conditions of an intertemporal choice paradigm using sucrose solution as reward. In both conditions, the LL was 150 microl delayed by 3 s, while the SS was an immediate reward that ranged from 25-150 microl across sessions. Preference for the LL was greater when the chosen reward was automatically delivered three times in succession (bundled) than when it was chosen singly and delivered after each choice. For each of the 8 rats, the estimated SS amount that produced indifference was higher in the bundled condition than in the single condition. Because bundling in humans may be based on the perception that one's current choice is predictive of future choices, the data presented here may demonstrate an important building block of self-control.     

A different kind of pain: affective valence of errors and incongruence*

People hiss and swear when they make errors, frown and swear again when they encounter conflicting information. Such error- and conflict-related signs of negative affect are found even when there is no time pressure or external reward and the task itself is very simple. Previous studies, however, provide inconsistent evidence regarding the affective consequences of resolved conflicts, that is, conflicts that resulted in correct responses. We tested whether response accuracy in the Eriksen flanker task will moderate the effect of trial incongruence using affective priming to measure positive and negative affect. We found that responses to incongruent trials elicit positive affect irrespective of their accuracy. Errors, in turn, result in negative affect irrespective of trial congruence. The effects of conflicts and errors do not interact and affect different dimensions of affective priming. Conflicts change the speed of evaluative categorisation while errors are reflected in categorisation accuracy. We discuss the findings in light of the “reward value and prediction” model and the “affect as a feedback for predictions” framework and consider the possible mechanisms behind the divergent effects.     

Rhesus monkeys lack a consistent peak-end effect

In humans, the order of receiving sequential rewards can significantly influence the overall subjective utility of an outcome. For example, people subjectively rate receiving a large reward by itself significantly higher than receiving the same large reward followed by a smaller one (Do, Rupert, & Wolford, 2008). This result is called the peak-end effect. A comparative analysis of order effects can help determine the generality of such effects across primates, and we therefore examined the influence of reward-quality order on decision making in three rhesus macaque monkeys (Macaca mulatta). When given the choice between a high-low reward sequence and a low-high sequence, all three monkeys preferred receiving the high-value reward first. Follow-up experiments showed that for two of the three monkeys their choices depended specifically on reward-quality order and could not be accounted for by delay discounting. These results provide evidence for the influence of outcome order on decision making in rhesus monkeys. Unlike humans, who usually discount choices when a low-value reward comes last, rhesus monkeys show no such peak-end effect.