Correcting for base rates in multidimensional “Who said what?” experiments

Do conspiracy theories efficiently signal coalition membership? An experimental test using the "Who Said What?" design

Theoretical work in evolutionary psychology have proposed that conspiracy theories may serve a coalitional function. Specifically, fringe and offensive statements such as conspiracy theories are expected to send a highly credible signal of coalition membership by clearly distinguishing the speaker's group from other groups. A key implication of this theory is that cognitive systems designed for alliance detection should intuitively interpret the endorsement of conspiracy theories as coalitional cues. To our knowledge, no previous studies have empirically investigated this claim. Taking the domain of environmental policy as our case, we examine the hypothesis that beliefs framed in a conspiratorial manner act as more efficient coalitional markers of environmental position than similar but non-conspiratorial beliefs. To test this prediction, quota sampled American participants (total N = 2462) completed two pre-registered Who-Said-What experiments where we measured if participants spontaneously categorize targets based on their environmental position, and if this categorization process is enhanced by the use of a conspiratorial frame. We find firm evidence that participants categorize by environmental position, but no evidence that the use of conspiratorial statements increases categorization strength and thus serves a coalitional function.

The correct way to test the hypothesis that racial categorization is a byproduct of an evolved alliance-tracking capacity

The project of identifying the cognitive mechanisms or information-processing functions that cause people to categorize others by their race is one of the longest-standing and socially-impactful scientific issues in all of the behavioral sciences. This paper addresses a critical issue with one of the few hypotheses in this area that has thus far been successful-the alliance hypothesis of race-which had predicted a set of experimental circumstances that appeared to selectively target and modify people's implicit categorization of others by their race. Here, we will show why the evidence put forward in favor of this hypothesis was not in fact evidence in support of the hypothesis, contrary to common understanding. We will then provide the necessary and crucial tests of the hypothesis in the context of conflictual alliances, determining if the predictions of the alliance hypothesis of racial categorization in fact hold up to experimental scrutiny. When adequately tested, we find that indeed categorization by race is selectively reduced when crossed with membership in antagonistic alliances-the very pattern predicted by the alliance hypothesis. This finding provides direct experimental evidence that the human mind treats race as proxy for alliance membership, implying that racial categorization does not reflect attention to physical features per se, but rather to social relationships.

A Meta-Analysis of the "Erasing Race" Effect in the United States and Some Theoretical Considerations

The "erasing race" effect is the reduction of the salience of "race" as an alliance cue when recalling coalition membership, once more accurate information about coalition structure is presented. We conducted a random-effects model meta-analysis of this effect using five United States studies (containing nine independent effect sizes). The effect was found (ρ = 0.137, K = 9, 95% CI = 0.085 to 0.188). However, no decline effect or moderation effects were found (a "decline effect" in this context would be a decrease in the effect size over time). Furthermore, we found little evidence of publication bias. Synthetically correcting the effect size for bias stemming from the use of an older method for calculating error base rates reduced the magnitude of the effect, but the it remained significant. Taken together, these findings indicate that the "erasing race" effect generalizes quite well across experimental contexts and would, therefore, appear to be quite robust. We reinterpret the theoretical basis for these effects in line with Brunswikian evolutionary-developmental theory and present a series of predictions to guide future research in this area.