https://phys.org/news/2019-07-people-overconfidence.html Study: People may use overconfidence to persuade or deceive others: A pair of researchers, one from the University of Munich, the other the University of Amsterdam has found that people may behave with overconfidence as a means to persuade or deceive other people. In their paper published in the journal Nature Human Behavior, Peter Schwardmann and Joël van der Weele describe a two-stage experiment they carried out with volunteers and what they found. Scientists who study human behavior have found through various studies that most people tend to overrate their own abilities or characteristics. Most people think they are smarter than they actually are, for example. And most people seem to think they are better drivers than all the others on the road. But why is this? In this new effort, Schwardmann and van der Weele sought to find out if there might be an advantage to being overconfident—to that end, they carried out a two-stage experiment designed to reveal possible advantages. more at link..... the paper: https://www.nature.com/articles/s41562-019-0666-7 Deception and self-deception: Abstract: There is ample evidence that the average person thinks he or she is more skilful, more beautiful and kinder than others1,2 and that such overconfidence may result in substantial personal and social costs3,4,5,6,7,8. To explain the prevalence of overconfidence, social scientists usually point to its affective benefits, such as those stemming from a good self-image or reduced anxiety about an uncertain future9,10,11,12,13. An alternative theory, first advanced by evolutionary biologist Robert Trivers14,15,16, posits that people self-deceive into higher confidence to more effectively persuade or deceive others. Here we conduct two experiments (combined n = 688) to test this strategic self-deception hypothesis. After performing a cognitively challenging task, half of our subjects are informed that they can earn money if, during a short face-to-face interaction, they convince others of their superior performance. We find that the privately elicited beliefs of the group that was informed of the profitable deception opportunity exhibit significantly more overconfidence than the beliefs of the control group. To test whether higher confidence ultimately pays off, we experimentally manipulate the confidence of the subjects by means of a noisy feedback signal. We find that this exogenous shift in confidence makes subjects more persuasive in subsequent face-to-face interactions. Overconfidence emerges from these results as the product of an adaptive cognitive technology with important social benefits, rather than some deficiency or bias.