The relationship between anomalistic belief and biases of evidence integration and jumping to conclusions

Biases in the assessment and integration of evidence are likely contributors to anomalistic (e.g., paranormal, extra-terrestrial) beliefs because of the non-evidence based nature of these beliefs. However, little research has examined the relationship between anomalistic beliefs and evidence integration biases. The current study addressed this gap by examining the relationship between anomalistic belief and four such biases; bias against disconfirmatory evidence (BADE), bias against confirmatory evidence (BACE), liberal acceptance bias, and the jumping to conclusions bias (JTC). Standard BADE scenarios were used to measure BADE, BACE, and the liberal acceptance bias: Participants were given three pieces of evidence, one at a time, and required to rate several alternative explanations. The JTC was measured using two draws-to-decisions tasks (beads and emotionally salient), and participants also completed measures of anomalistic belief and delusion-proneness. Results showed that liberal acceptance was the only evidence integration bias that significantly predicted greater overall anomalistic belief. However, this relationship was no longer significant once delusion proneness was controlled for. Additionally, BADE significantly predicted experiential (but not other types of) anomalistic beliefs even after controlling for delusion proneness. We propose that liberal acceptance may lead people to form anomalistic beliefs on the basis of little evidence, and that stronger BADE may make these beliefs highly resistant to change.