'Jumping to Conclusions', or hasty decision making, is widely studied within clinical and computational psychology. It is typically investigated using the 'beads task', a sequential information sampling paradigm, and defining one or two draws as jumping to conclusion. Situational experimental conditions, e.g., group vs. individual testing, abstract vs. cover story, show-up fee or course credit, frequently vary between studies. Little effort has been dedicated to investigating the potential effects of demand characteristics on hasty decision making. We explored this in four samples of participants (n = 336), in different situational experiment conditions, with two distinct variations of the beads task. An abstract 'Draws to Decision' (DtD) variant, and a cover story combined DtD and probabilistic inferences variant. Situational conditions did not have a significant effect on overall DtD for either variant. However, when using 'extreme scores' (DtD of 1 or 1 to 2) as a measure of hasty decision making, situational conditions had an effect for the abstract variant, with individual testing having the fewest hasty decision makers (DtD1: Mann-Whitney U = 2137.5, p = 0.02; DtD1-2: Mann-Whitney U = 2017.5, p < 0.01), but not for the cover story variant. Our results suggest that the abstract variant is more susceptible to test conditions, especially if a categorisation is used to classify hasty decisions. This does not imply that the cover story variant is better suited to capturing jumping to conclusions behaviour, but highlights the importance of mirroring the situational conditions between different samples. We recommend that testing conditions should be fully disclosed.
Keywords: delusion; demand characteristics; experimenter bias; information sampling; jumping to conclusions.