Information Bias

Information bias, in the context of decision-making, is the tendency to seek out additional information before making a decision even when that extra information could not actually change the decision. The psychologists Jonathan Baron, Jane Beattie and John Hershey demonstrated the effect in a 1988 study using a diagnostic scenario in which a patient had an 80 percent probability of having a fictitious disease called globoma, with only one alternative diagnosis possible; a further diagnostic test could not change the treatment decision either way, since the probability of globoma would remain the same regardless of the test's result, yet many participants still insisted they would want the test performed. The study's mathematical analysis confirmed the test provided no information capable of altering the appropriate course of action, showing that people often value the act of gathering more information over a rational assessment of whether that information would actually affect their choice.