It happens because I'm watching it: Observing an uncertain event can affect subjective probability judgments

Abstract

AbstractA longstanding body of research has investigated various factors that bias subjective probability judgments. The current research explores a novel bias in judgments of probability—that observing an event affects probability estimation of the event's outcome. Our findings from multiple online and laboratory experiments demonstrate that individuals overestimate the likelihood of a positive outcome occurring when they observe (vs. do not observe) the uncertain event unfolding in front of them. Study 1 explores the effect of watching on probability estimation using a random card draw conducted in an auditorium. Studies 2 and 3 use an online procedure to further demonstrate the effect. In Study 4 we manipulated an illusory sense of control followed by a football game scenario and in Study 5 we used a live versus previously recorded urn game to further investigate the watching effect. We suggest that illusion of control, wishful thinking, and availability are among the possible explanations for this effect.