Digital Nudging and Cookie Rejection : An Experiment

When browsing the Internet, web users tend to accept all cookies even though this may threaten their online security. We apply a salience nudge and a framing nudge to the design of a cookie banner and experimentally test their individual and combined effectiveness in increasing the rate at which users reject unnecessary cookies. The salience nudge makes the rejection button more visible, and the framing nudge phrases button labels as negations. The experiment involved 358 subjects and employed a 2⨉2 between-subject design. The salience nudge increased cookie rejection rate by 7 percentage points (but p = 0.305), the framing nudge by 18pp (p = 0.009), and the combination of the two by 53pp (p <0.001). We also investigate how the frequency with which users reject cookies is related to the time they spend making the decision and to their personality traits. Our findings suggest that cookie rejection can indeed be fostered by an appropriate design of cookie banners and that, to be effective, legislation for protecting the online security of users should introduce specific guidelines for the design of banners