Are we certain about which measure of intolerance of uncertainty to use yet?

Intolerance of Uncertainty (IU) has been understood as a dispositional tendency to view the presence of negative events as unacceptable and threatening, regardless of the likelihood of those events occurring. The preference over the 12-item vs. 27-item of the IUS has been central to debate. The goals of the present study were to evaluate two competing models of measuring IU with model-fitting analyses and explore model invariance of gender (e.g. men vs. women). A sample of 980 individuals completed an online IUS survey. Results indicated that the two-factor short-form model provided better fit to the data compared to the full-length two-factor model proposed by. Results also indicated that the short-form IUS is gender invariant, suggesting acceptable use among men and women. These findings provide further support of a two-factor structure and suggest that the IUS is appropriate for men and women.     

Capuchin monkeys, inequity aversion, and the frustration effect

Each of 4 female capuchin monkeys ("model") was paired with another female capuchin ("witness") in an adjacent cage. In Phases 1 and 3, a model could remove a grape from the experimenter's hand while the witness watched. The witness was then offered a slice of cucumber, a less preferred food. Trials alternated between subjects 50 times, defining a session. In Phases 2 and 4, both were offered cucumber. Witness rejections of cucumber were infrequent and were not dependent on whether models received grape or cucumber. When models were offered cucumber, they rejected it at higher rates than did witnesses. These results fail to support findings of Brosnan and de Waal. An account based on the frustration effect accommodates these results and those of Brosnan and de Waal.