Speaking on Data's Behalf: What Researchers Say and How Audiences Choose.

BACKGROUND: Bayesian statistics have become popular in the social sciences, in part because they are thought to present more useful information than traditional frequentist statistics. Unfortunately, little is known about whether or how interpretations of frequentist and Bayesian results differ. OBJECTIVES: We test whether presenting Bayesian or frequentist results based on the same underlying data influences the decisions people made. RESEARCH DESIGN: Participants were randomly assigned to read Bayesian and frequentist interpretations of hypothetical evaluations of new education technologies of various degrees of uncertainty, ranging from posterior probabilities of 99.8% to 52.9%, which have equivalent frequentist p values of .001 and .65, respectively. SUBJECTS: Across three studies, 933 U.S. adults were recruited from Amazon Mechanical Turk. MEASURES: The primary outcome was the proportion of participants who recommended adopting the new technology. We also measured respondents' certainty in their choice and (in Study 3) how easy it was to understand the results. RESULTS: When presented with Bayesian results, participants were more likely to recommend switching to the new technology. This finding held across all degrees of uncertainty, but especially when the frequentist results reported a p value >.05. Those who recommended change based on Bayesian results were more certain about their choice. All respondents reported that the Bayesian display was easier to understand. CONCLUSIONS: Presenting the same data in either frequentist or Bayesian terms can influence the decisions that people make. This finding highlights the importance of understanding the impact of the statistical results on how audiences interpret evaluation results.

Data from a pre-publication independent replication initiative examining ten moral judgement effects.

We present the data from a crowdsourced project seeking to replicate findings in independent laboratories before (rather than after) they are published. In this Pre-Publication Independent Replication (PPIR) initiative, 25 research groups attempted to replicate 10 moral judgment effects from a single laboratory's research pipeline of unpublished findings. The 10 effects were investigated using online/lab surveys containing psychological manipulations (vignettes) followed by questionnaires. Results revealed a mix of reliable, unreliable, and culturally moderated findings. Unlike any previous replication project, this dataset includes the data from not only the replications but also from the original studies, creating a unique corpus that researchers can use to better understand reproducibility and irreproducibility in science.

Lost in the crowd: entitative group membership reduces mind attribution.

This research examined how and why group membership diminishes the attribution of mind to individuals. We found that mind attribution was inversely related to the size of the group to which an individual belonged (Experiment 1). Mind attribution was affected by group membership rather than the total number of entities perceived at once (Experiment 2). Moreover, mind attribution to an individual varied with the perception that the individual was a group member. Participants attributed more mind to an individual that appeared distinct or distant from other group members than to an individual that was perceived to be similar or proximal to a cohesive group (Experiments 3 and 4). This effect occurred for both human and nonhuman targets, and was driven by the perception of the target as an entitative group member rather than by the knowledge that the target was an entitative group member (Experiment 5).

Fast thought speed induces risk taking.

In two experiments, we tested for a causal link between thought speed and risk taking. In Experiment 1, we manipulated thought speed by presenting neutral-content text at either a fast or a slow pace and having participants read the text aloud. In Experiment 2, we manipulated thought speed by presenting fast-, medium-, or slow-paced movie clips that contained similar content. Participants who were induced to think more quickly took more risks with actual money in Experiment 1 and reported greater intentions to engage in real-world risky behaviors, such as unprotected sex and illegal drug use, in Experiment 2. These experiments provide evidence that faster thinking induces greater risk taking.