The relationship between anomalistic belief, misperception of chance and the base rate fallacy

Abstract

A poor understanding of probability may lead people to misinterpret every day coincidences and form anomalistic (e.g., paranormal) beliefs. We investigated the relationship between anomalistic belief (including type of belief) and misperception of chance and the base rate fallacy across both anomalistic and control (i.e., neutral) contexts. Greater anomalistic belief was associated with poorer performance for both types of items; however there were no significant interactions between belief and context. For misperception of chance items, only experiential (vs. theoretical) anomalistic beliefs predicted more errors. In contrast, overall anomalistic belief was positively related to the base rate fallacy but no specific subtype of anomalistic belief was a significant predictor. The results indicate misperception of chance may lead people to interpret coincidental events as having an anomalistic cause, and a poor understanding of base rates may make people more prone to forming anomalistic beliefs.

Keywords:

• Anomalistic belief
• paranormal belief
• probabilistic reasoning
• misperception of chance
• base rate fallacy

Acknowledgements

Portions of this research were presented at the 57th Annual Meeting of the Psychonomic Society, Boston, Massachusetts, USA. The data supporting the conclusions of this article are available at: https://osf.io/ygns3/ (DOI: 10.17605/OSF.IO/YGNS3). Raw data are also available from the authors upon request.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 Dagnall et al. (2016) did not report whether the correlations were statistically significantly different, however, we tested if they statistically significantly differed using methods outlined in Steiger (1980).

2 The difference between correlations again was not reported in Dagnall et al. (2016), thus we tested if they statistically significantly differed using methods outlined in Steiger (1980).

3 Minimum timing was decided based on the time taken to complete the survey without reading and maximum time was decided so that participants could complete the study at a leisurely pace. Average time taken to complete the study was approximately half an hour (before participants removed, M = 27.51, SD = 15.19; after participants removed for timing, M = 27.55, SD = 11.13).

4 The overall paranormal and extra-terrestrial belief questions showed the same patterns as the ABS and ASGS belief scales and/or the relevant factors of the ABS, however, the belief scales and factors provided a better understanding of the relationship between probabilistic reasoning and anomalistic belief. Therefore, the overall questions are not discussed further (see Supplementary Material).

5 The default priors used in JASP for Bayesian repeated measures ANOVAs are r scale fixed effects = 0.5, r scale random effects = 1, and r scale covariates = 0.354. For Bayesian linear regressions JASP uses a default prior of r scale = 0.354. All priors use a Cauchy distribution with r = $1\mathrm{ }/\surd 2$.

6 The reported degrees of freedom vary because some of the analyses include the ABS factors, and some include only an overall anomalistic belief measure (i.e., analyses with the ABS factors include an extra three variables and therefore the degrees of freedom are reduced).

7 Analyses to test for significant differences in the strength of the relationships between the factors and the outcome variables (misperception of chance and base rate fallacy) were conducted based on methods described in Cohen and Cohen (1983) for testing differences between regression coefficients from the same regression equation.

Additional information

Funding

Toby Prike was supported by an Australian Government Research Training Program Scholarship.