More is easier? Testing the role of fluency in the more-credible effect

People are more likely to endorse statements of the form "A is more than B" than those of the form "B is less than A", even though the ordinal relationship being described is identical in both cases -– a result I dub the "more-credible" effect. This paper reports 9 experiments (total = 5643) that probe the generality and basis for this effect. Studies 1–4 replicate the effect for comparative statements relating to environmental change and sustainable behaviours, finding that it is robust to changes in participant population, experimental design, response formats and data analysis strategy. However, it does not generalize to all stimulus sets. Studies 5–9 test the proposition that the effect is based on the greater ease of processing "more than" statements. I find no meaningful effect of warning people not to base their judgments on the fluency of the sentences (Studies 5 and 6), but do find associations between comparative language, credibility, and processing time: when the more-credible effect manifests, the more-than statements are read more quickly than the less-than statements, and this difference partly mediates the effect of comparative on agreement with the statements; in contrast, for a set of comparisons for which changes in the more/less framing did not affect truth judgments, there was no meaningful difference in the time taken to read the more- and less-than versions of the statements. Taken together, these results highlight the importance of comparative language in shaping the credibility of important socio-political messages, and provide some limited support for the idea that the effect of language choice is partly due to differences in how easily the statements can be processed -– although other mechanisms are also likely to be at work

If John is taller than Jake, where is John? Spatial inference from magnitude comparison

We regularly compare magnitudes and describe these comparisons to other people. This article reports 9 experiments that examine how messages about the relative magnitude of two items affect inferences about the items’ spatial arrangement. Native English speakers were given sentences such as “One tree is taller than the other,” and their beliefs about the left–right arrangement of the objects were probed. Across a wide range of dimensions and tasks, the choice of comparative shaped spatial inference: “Smaller” comparatives (e.g., shorter, lighter, less) led to the belief that the small item was on the left, whereas “larger” comparatives (e.g., longer, heavier, more) led to the belief that the small item was on the right. These inferences match the tendency of message senders to choose comparatives based on spatial layout, such that purely ordinal magnitude comparisons communicate information about the spatial arrangement of the compared objects. There was also evidence for a canonical “small–large” inference, consistent with the tendency of English speakers to associate “small” with “left” and “large” with “right”; however, this effect was task-dependent, indicating a flexible, language-based mapping rather than an immutable bias. Finally, there was evidence that the choice of comparative influenced the salience of particular response options. These results help to elucidate the deep interconnections between language, space, and magnitude: Linguistic tokens and structures reflect physical reality and, in turn, shape mental representations of the physical world

The effect of leg-to-body ratio on male attractiveness depends on the ecological validity of the figures

Leg-to-body ratio (LBR) predicts evolutionary fitness, and is therefore expected to influence bodily attractiveness. Previous investigations of LBR attractiveness have used a wide variety of stimuli, including line drawings, silhouettes, and computer-generated images based on anthropometric data. In two studies, community samples of heterosexual women from the USA rated the attractiveness of male figures presented as silhouettes and as detailed computer-generated images with 3 different skin tones (white, black, and an artificial grey). The effects of LBR depended on the image format. In particular, a curve-fitting analysis indicated that the optimally-attractive LBR for silhouettes was fractionally below the baseline, whereas the optima for more detailed computer-generated images was approximately 0.5 SD above the baseline and was similar for all three skin-tones. In addition, the participants’ sensitivity to changes in the LBR was lowest for the silhouettes and highest for the grey figures. Our results add to evidence that the most attractive LBR is close to, but slightly above, the population mean, and caution that the effects of limb proportions on attractiveness depend on the ecological validity of the figures

Further evidence that the effects of repetition on subjective time depend on repetition probability

Repeated stimuli typically have shorter apparent duration than novel stimuli. Most explanations for this effect have attributed it to the repeated stimuli being more expected or predictable than the novel items, but an emerging body of work suggests that repetition and expectation exert distinct effects on time perception. The present experiment replicated a recent study in which the probability of repetition was varied between blocks of trials. As in the previous work, the repetition effect was smaller when repeats were common (and therefore more expected) than when they were rare. These results add to growing evidence that, contrary to traditional accounts, expectation increases apparent duration whereas repetition compresses subjective time, perhaps via a low-level process like adaptation. These opposing processes can be seen as instances of a more general “processing principle”, according to which subjective time is a function of the perceptual strength of the stimulus representation, and therefore depends on a confluence of “bottom-up” and “top-down” variables.This research was supported by ESRC studentship ES/J500045/1

A Thin Slice of Science Communication: Are People’s Evaluations of TED Talks Predicted by Superficial Impressions of the Speakers?

First impressions based on physical characteristics and superficial information predict a wide variety of social judgments and outcomes. We build on recent work examining the effects of such impressions on the communication of scientific research and ideas to the general public. A large diverse sample viewed and evaluated scientific TED talks, while a separate group viewed short, silent excerpts of each video and judged the speakers on three core sociocognitive traits: competence, morality, and sociability. Neither the perceived scientific quality nor the entertainment value of the talks was meaningfully predicted by the thin-slice judgments; likewise, they were independent of the speakers’ age, gender, ethnicity, and attractiveness. We propose that these null results arise because the influence of superficial visual cues was overwhelmed by the wealth of more diagnostic information and by our participants’ attentiveness to this information. Our results suggest limits to the predictive power of superficial impressions. </jats:p

Inference and preference in intertemporal choice

When choosing between immediate and future rewards, how do people deal with uncertainty about the value of the future outcome or the delay until its occurrence? Skylark et al. (2020) suggested that people employ a delay-reward heuristic: the inferred value of an ambiguous future reward is a function of the stated delay, and vice-versa. The present paper investigates the role of this heuristic in choice behaviour. In Studies 1a–2b, participants inferred the value of an ambiguous future reward or delay before the true value was revealed and a choice made. Preference for the future option was predicted by the discrepancy between the estimated and true values: the more pleasantly surprising the delayed option, the greater the willingness to choose it. Studies 3a–3c examined the association between inference and preference when the ambiguous values remained unknown. As predicted by the use of a delay-reward heuristic, inferred delays and rewards were positively related to stated rewards and delays, respectively. More importantly, choices were associated with inferred rewards and, in some circumstances, delays. Critically, estimates and choices were both order-dependent: when estimates preceded choices, estimates were more optimistic (people inferred smaller delays and larger rewards) and were subsequently more likely to choose the delayed option than when choices were made before estimates. These order effects argue against a simple model in which people deal with ambiguity by first estimating the unknown value and then using their estimate as the basis for decision. Rather, it seems that inferences are partly constructed from choices, and the role of inference in choice depends on whether an explicit estimate is made prior to choosing. Finally, we also find that inferences about ambiguous delays depend on whether the estimate has to be made in "days" or in a self-selected temporal unit, and replicate previous findings that older participants make more pessimistic inferences than younger ones. We discuss the implications and possible mechanisms for these findings

The effect of autism on information sampling during decision-making: An eye-tracking study

AbstractRecent research has highlighted a tendency for more rational and deliberative decision-making in individuals with autism. We tested this hypothesis by using eye-tracking to investigate the information processing strategies that underpin multi-attribute choice in a sample of adults diagnosed with autism spectrum condition. We found that, as the number of attributes defining each option increased, autistic decision-makers were speedier, examined less of the available information, and spent a greater proportion of their time examining the option they eventually chose. Rather than indicating a more deliberative style, our results are consistent with a tendency for individuals with autism to narrow down the decision-space more quickly than does the neurotypical population.This research was funded by a Wellcome Trust (grant RG76641) and Isaac Newton Trust grant (Grant RG70368). GF was also supported by a Wellcome ISSF award (204796/Z/16/Z). PS was supported by the Autism Research Trust and the Wellcome Trust. SBC received funding from the Wellcome Trust 214322/Z/18/Z. In addition, SBC received funding from Innovative Medicines Initiative 2 Joint Undertaking (JU) under grant agreement No 777394. The JU receives support from the European Union’s Horizon 2020 research and innovation programme and EFPIA and AUTISM SPEAKS, Autistica, SFARI. SBC also received funding from the Autism Research Trust, SFARI, the Templeton World Charitable Fund, SFARI, and the NIHR Cambridge Biomedical Research Centre. The research was supported by the (U.K.) National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care East of England at Cambridgeshire and Peterborough NHS Foundation Trust

A new test of the risk-reward heuristic

Risk and reward are negatively correlated in a wide variety of environments, and in many cases this trade off approximates a fair bet. Pleskac and Hertwig (2014) recently proposed that people have internalized this relationship and use it as the basis for probability estimation and subsequent choice under conditions of uncertainty. Specifically, they showed that risky options with high-value outcomes are inferred to have lower probability than options offering a less valuable reward. We report two experiments that test a simple corollary of this idea. In both studies, participants estimated the magnitude of prizes offered by lotteries with known win-probabilities. The relationship between estimates and probabilities followed the power relationship predicted by the risk-reward heuristic, albeit with a tendency to overestimate outcome magnitude. In addition, people’s estimates predicted their willingness to take the gamble. Our results provide further evidence that people have internalized the ecological relationship between risk and reward in financial lotteries, and we suggest that this relationship exerts a wide-ranging influence on decision-making

Reexamining how utility and weighting functions get their shapes: A quasi-adversarial collaboration providing a new interpretation

In a paper published in Management Science in 2015, Stewart, Reimers, and Harris (SRH) demonstrated that shapes of utility and probability weighting functions could be manipulated by adjusting the distributions of outcomes and probabilities on offer as predicted by the theory of decision by sampling. So marked were these effects that, at face value, they profoundly challenge standard interpretations of preference theoretic models in which such functions are supposed to reflect stable properties of individual risk preferences. Motivated by this challenge, we report an extensive replication exercise based on a series of experiments conducted as a quasi-adversarial collaboration across different labs and involving researchers from both economics and psychology. We replicate the SRH effect across multiple experiments involving changes in many design features; importantly, however, we find that the effect is also present in designs modified so that decision by sampling predicts no effect. Although those results depend on model-based inferences, an alternative analysis using a model-free comparison approach finds no evidence of patterns akin to the SRH effect. On the basis of simulation exercises, we demonstrate that the SRH effect may be a consequence of misspecification biases arising in parameter recovery exercises that fit imperfectly specified choice models to experimental data. Overall, our analysis casts the SRH effect in an entirely new light. This paper was accepted by Yuval Rottenstreich, judgment and decision making </jats:p