Bragging to coworkers about a recent promotion, or posting a photo of your brand new car on Facebook, may seem like harmless ways to share good news. However, a new study from City University London, Carnegie Mellon University and Bocconi University shows that self-promotion or a "humblebrag" often backfires.

Published in Psychological Science, Irene Scopelliti, George Loewenstein and Joachim Vosgerau wanted to find out why so many people frequently get the trade-off between self-promotion and modesty wrong. They found that self-promoters overestimate how much their self-promotion elicits positive emotions and underestimate how much it elicits negative emotions. As a consequence, when people try to increase the favorability of the opinion others have of them, they excessively self-promote, which has the opposite of the intended effect.

"Most people probably realize that they experience emotions other than pure joy when they are on the receiving end of someone else's self-promotion. Yet, when we engage in self-promotion ourselves, we tend to overestimate others' positive reactions and underestimate their negative ones," said Scopelliti, the study's lead author and a lecturer in marketing at City University London who conducted the research while a postdoctoral fellow at Carnegie Mellon.

"These results are particularly important in the Internet age, when opportunities for self-promotion have proliferated via social networking. The effects may be exacerbated by the additional distance between people sharing information and their recipient, which can both reduce the empathy of the self-promoter and decrease the sharing of pleasure by the recipient," she said.

For the study, the researchers ran two experiments to find evidence of the misperception.. A third experiment examined the consequences of the miscalibration, revealing that recipients of excessive self-promotion view self-promoters as less likeable and as braggarts.

"This shows how often, when we are trying to make a good impression, it backfires," said Loewenstein, the Herbert A. Simon University Professor of Economics and Psychology in CMU's Dietrich College of Humanities and Social Sciences. "Bragging is probably just the tip of the iceberg of the self-destructive things we do in the service of self-promotion, from unfortunate flourishes in public speeches to inept efforts to 'dress for success' to obviously insincere attempts to ingratiate ourselves to those in power."