Self-Preferencing in Digital Markets: The Role of Behavioral Biases in the Google Search Case

Details

Supervisors

Johnen, Johannes

Faculty

Faculté des sciences économiques, sociales, politiques et de communication

Degree label

Master [120] en sciences économiques, orientation générale, à finalité spécialisée

Abstract

enThis dissertation investigates whether Google exploits consumer behavioral biases to practice self-preferencing, or whether its interface design simply helps rational users find better results faster. Two competing hypotheses organize the analysis. Under H1, Google's choice architecture exploits limited attention, default inertia, and visual salience to generate a click advantage independent of product quality. Under H2, the same design elements reduce search costs and reflect genuine quality superiority. The existing evidence is more consistent with H1 than H2. One third of users are persistently inattentive, active choice produces negligible switching, and visual salience captures attention before rational evaluation begins. However, no decisive experimental test exists yet. The dissertation proposes four experimental designs that would close this gap and identifies four specific limitations of the Digital Markets Act for persistently inattentive consumers, advancing two concrete policy recommendations.