As reported in the Independent, research published in the Journal of Personality and Social Psychology, has found that "people in higher social classes are 'overconfident' about their abilities which means they come across as more competent – even when they don’t know what they’re talking about. Being able to confidently express what they think means a tendency to perform better during job interviews, opposed to working-class people, who are socialised to embrace humility and authenticity."
The research could help explain why "class-based hierarchies persist generation after generation. Psychologists believe that inequalities will continue to perpetuate if people continue to conflate impressions of confidence with evidence of ability."
Read the full article here, and a press release here, with a link to the journal article.