What makes you so sure? Effects of epistemic motivations on judgmental confidence

Three experiments examined the effects of motivational variables on the epistemic (or knowledge acquisition) process. The motivations considered were need for cognitive structure and fear of invalidity, and the epistemic phenomena studied were subjective confidence and hypothesis generation. In the first experiment a tachistoscopic task was employed to examine the effects of fear of invalidity upon (1) subjects' initial and final confidence in a hypothesis and (2) shifts in confidence occasioned by successive items of new information. The second experiment replicated and extended the first by investigating the effects of need for structure over and above those of fear of invalidity. The third experiment employed an object recognition task and investigated the process of hypothesis generation assumed to mediate motivational effects on subjective confidence. It was found that both initial confidence and informationally induced confidence shifts were of higher magnitude when subjects' need for structure was high rather than low, and when subjects' fear of invalidity was low rather than high. Furthermore, the number of alternate hypotheses generated was higher under high (versus low) fear of invalidity, and low (vs high) need for structure. The above findings were discussed in reference to Kruglanski's theory of lay epistemology.