SAVING THE BEST FOR LAST? A CROSS-SPECIES ANALYSIS OF CHOICES BETWEEN REINFORCER SEQUENCES

Two experiments were conducted to compare choices between sequences of reinforcers in pigeon (Experiment 1) and human (Experiment 2) subjects, using functionally analogous procedures. The subjects made pairwise choices among 3 sequence types, all of which provided the same overall reinforcerment rate, but differed in their temporal patterning. Token reinforcement schedules were used in both experiments and the type of exchange schedule varied across blocks of sessions. Some conditions permitted immediate exchange of tokens for consumable reinforcers (food for pigeons, video access for humans); in other conditions, tokens accumulated and were exchanged for consumable reinforcers only at the end of the sequence. Choice patterns in the immediate-exchange conditions were generally similar across species, with both pigeons and humans preferring sequences with the shortest delay to the initial reinforcer in the series. The results are broadly consistent with models of temporal discounting expanded to include the impact of sequences of delayed reinforcers acting in parallel from the time of the choice. Preferences were less consistent with discounting models in the delayed exchange conditions. Questionnaire data gathered at the end of the experiment were consistent with prior results of questionnaire studies, but showed no straightforward relation to the observed choice patterns, urging caution in the extrapolation of results from one decision-making domain to the other.     

Normative influence on retirement savings decisions: Do people care what employers and the government want?

The need for Australians to increase retirement savings has been widely promoted. Yet our understanding of the motivations of individuals to save at a higher rate remains sparse. This article reports the findings of a survey of superannuation fund members and their intentions to contribute more to superannuation and to manage their investment strategy. The article uses the theory of planned behaviour to focus on the important motivational influence of social norms. Formative research identified a number of influential social referents. Among identified referents, the study found that spouses appear to be the primary source of social influence for retirement savings decisions. The government and employers appear to exert little influence, and financial advisors and superannuation funds take up the middle ground of social influence. Possibilities for interventions designed to influence behaviour are discussed; however, conclusions are tempered by the fact that correspondence between intention and behaviour is not tested in the present research.     

The preference for symmetry in flower-naïve and not-so-naïve bumblebees

Truly flower-naïve bumblebees, with no prior rewarded experience for visits on any visual patterns outside the colony, were tested for their choice of bilaterally symmetric over asymmetric patterns in a radial-arm maze. No preference for symmetry was found. Prior training with rewarded black and white disks did, however, lead to a significant preference for symmetry. The preference was not specific to symmetry along the vertical axis: a preference for horizontal symmetry was found as well. The results challenge the notion that a preference for bilateral symmetry is unlearned. The preference for symmetry was the product of non-differential conditioning.     

Transitional and steady-state choice behavior under an adjusting-delay schedule

Twelve rats made repeated choices on an adjusting-delay schedule between a smaller reinforcer (A) that was delivered immediately after a response and a larger reinforcer (B) that was delivered after a delay which increased or decreased by 20% depending on the subject's choices in successive blocks of trials. In two phases of the experiment (100 sessions and 40 sessions), reinforcer sizes were selected which enabled theoretical parameters expressing the rate of delay discounting and sensitivity to reinforcer size to be estimated from the ratio of the indifference delays obtained in the two phases. Indifference delays, calculated from adjusting delays in the last 10 sessions of each phase, were shorter when the sizes of A and B were 14 and 25 μl of a 0.6 M sucrose solution than when they were 25 and 100 μl of the same solution. The ratio of the indifference delays was significantly smaller than that predicted on the basis of an assumed linear relation between reinforcer size and instantaneous reinforcer value, consistent with a previous proposal that this relation may be hyperbolic in form. Estimates of the rate of delay discounting based on the ratio of the two indifference delays (mean, 0.08 s(-1)) were similar to values obtained previously using different intertemporal choice protocols. Estimates of the size-sensitivity parameter (mean 113 μl) were similar to estimates recently derived from performance on progressive-ratio schedules. In both phases of the experiment, adjusting delays in successive blocks of trials were analyzed using the Fourier transform. The power spectrum obtained from individual rats had a dominant frequency that corresponded to a period of oscillation of the adjusting delay between 30 and 100 trial blocks (mean, 78). Power in the dominant frequency band was highest in the early sessions of the first phase and declined with extended training. It is suggested that this experimental protocol may have utility in neurobehavioral studies of intertemporal choice.     

Women’s perception of men’s sensation seeking propensity from their dance movements

Risk-taking behaviour in men, an expression of the more general personality trait sensation seeking, has been hypothesized to be an evolved aspect of male psychology that arose through sexual selection. Sensation seeking could be seen as a costly behavioural trait that signals a man’s health and vigour and is preferred by women. This study extends knowledge about risk-taking as a cue in human mate choice by examining whether women can perceive men’s sensation seeking propensity (assessed with the Sensation Seeking Scale Form V; SSS-V) by viewing their dance movements. We videotaped 50 men’s dancing and had 60 women judge each dancer on perceived attractiveness and risk-taking. A positive and significant correlation was found between women’s attractiveness judgements and male’s SSS-V total score, thrill and adventure seeking, disinhibition and boredom susceptibility. Further, women’s risk-taking judgements were related to men’s boredom susceptibility. We conclude that (i) male sensation seeking propensity is signalled via their dance movements, and (ii) women are sensitive to these cues as they consider men who score high on sensation seeking as attractive. We discuss our results with reference to the evolutionary psychology concept of sexual selection and mate preferences.     

Rational Choice and Moral Decision Making in Research

University psychology and sociology researchers rated the likelihood they would engage in misconduct as described in 9 research scenarios, while also making moral judgments and rating the likelihood of discovery and sanctions. Multiple regression revealed significant effects across various scenarios for moral judgment as well as shame and embarrassment on reducing misconduct. The effects on misconduct of the perceived probability of sanctions were conditioned on moral judgments in some scenarios. The results have implications for how universities address the prevention, detection, and sanctioning of research misconduct.     

A Fuzzy Goal Programming Formulation with Multiple Target Levels

The essential activity of a manager is decision making, which is becoming more and more complex, mainly in the multi‐criteria problems. Multi‐choice goal programming (MCGP) is considered as a robust tool in operational research to solve this type of problem. However, in real world problems, determining precise targets for the goals is a difficult task. To deal with such situation, Tabrizi introduced and used in 2012 the concept of membership functions in the MCGP model in order to model the targets fuzziness of each goal. In their model, they considered just only one type of functions (triangular form), which does not reflect adequately the decision maker's preferences that are considered as an essential element for modelling the goal's fuzziness. Their model is called Fuzzy MCGP. In this paper, new ideas are presented to reformulate MCGP model to tackle all types of functions by introducing the (decision maker's) preferences. The concept of indifference thresholds is used in the new formulation for characterizing the imprecision and the preferences associated with all types of the goals. The proposed formulation provides useful insight about the solution of a new class of problems. A numerical example is given to demonstrate the validity and strength of the new formulation. Copyright © 2013 John Wiley & Sons, Ltd.     

Effects of self–other decision-making on time-based intertemporal choice

The effects of self–other decision-making on intertemporal choice have been revealed in many studies using a monetary outcome. However, the outcome of intertemporal choice is not restricted to money; time is also a scarce and nonrenewable resource outcome. Thus, we conducted a series of experiments to address the effects of self–other decision-making on time-based intertemporal choice, a type of intertemporal choice that uses time as an outcome. Over the course of three experiments, differences in self–other decision-making were evidenced. Participants who made decisions for others were more likely to prefer the smaller but sooner (SS) option over the larger but later (LL) option and considered the gain of the SS option to be significantly greater than that of the LL option. Participants who made decisions for themselves were likely to prefer the LL option over the SS option. However, they considered the gains of the LL and the SS option to be indifferent. Changing the role of decision-making could affect the ability of individuals to consider the future consequences of their decisions. The effects of self–other decision-making on time-based intertemporal choice could be explained by the accounts of economic reasoning and construal level theory. The findings indicated that the effects of self–other decision-making on time-based intertemporal choice, which could be generated simply by rewording questions, can help individuals make optimal long-term choices without the need for increased control.     

Behavior model and guidance strategies of the crossing behavior at unsignalized intersections in the connected vehicle environment

The connected vehicle environment is considered to be a disruptive technology that reconstructs the way people travel and road transport, and more importantly, ensures traffic safety. This study aims on investigating drivers’ interactive behavior at an unsignalized intersection in the connected vehicle environment. Specifically, a simplified iterative behavior model was established to predict the potential conflicting vehicles’ behavior. Furthermore, based on principles of safety, efficiency, and comfort, the guidance strategies were proposed to help the subject vehicles cross intersections. A multi-user driving simulator experiment was carried out and 48 participants were divided into 24 pairs to complete the test. The simplified iterative behavior model was constructed based on the dynamic interaction of each participant pair as they approached the intersection from straight-crossing directions. The comparison results showed the behavior model was an effective microscopic simulation tool for vehicles at unsignalized intersections with high accuracy and good applicability. Then, the guidance strategies under different compliance rates (baseline, 50 % compliance, 100% compliance) were evaluated based on three indexes i.e. standard deviation of speed (SDS), duration of crossing the intersection (DCI), and time exposed post-encroachment-time (TEP). The numerical simulation results showed that the guidance strategies could effectively improve the safety and efficiency of drivers crossing the intersection under both 50% and 100% compliance rates. Besides, with the increase of compliance rate, the comfort level also increased evidently. This study can provide theoretical and algorithmic references for microscopic simulation and guidance strategy at unsignalized intersections in the connected vehicle environment.     

不同抑郁症状青少年调节不同强度情绪时策略选择的差异

最新研究发现,情绪强度会影响健康个体的情绪调节策略选择。然而,至今尚未有研究考察情绪强度对不同抑郁症状青少年策略选择的影响。对此,本研究通过流调中心用抑郁量表划分出无抑郁、阈下抑郁和抑郁症青少年,进而考察其在面对高-低强度积极-消极日常情绪事件时选择认知重评和认知沉浸的差异。结果发现：当面对高强度积极情绪、低强度积极情绪和低强度消极情绪时,三组被试的策略选择均无显著差异;当面对高强度消极情绪时,无抑郁青少年比阈下抑郁和抑郁症青少年更多选择认知重评而更少选择认知沉浸,但阈下抑郁和抑郁症青少年之间无显著差异。结果表明：不同抑郁症状青少年在面对不同强度和效价情绪时的情绪调节策略选择存在差异,表现为高强度消极情绪下抑郁症状越多的青少年越少选择认知重评而越多选择认知沉浸。这一发现有助于识别和干预青少年的抑郁症状。