Date of Award


Embargo Period


Degree Type


Degree Name

Doctor of Philosophy (PhD)


Public Policy and Management


Alessandro Acquisti


The first decade of the 21st century has witnessed the rise of Web 2.0 technologies that allow users to create and share content online with friends – and strangers alike. These technologies have generated an ‘enthusiasm for sharing’ as well as privacy concerns that researchers, organizations and policy makers often measure and debate. After introducing the trade-offs of information sharing (Chapter 1), I investigate one of the antecedents of willingness to share personal information – namely, perceived control – as a possible explanation for the success of online social media, notwithstanding people’s diffuse concern for privacy protection. The results challenge the consensus view of control as a sufficient means of privacy protection, since increased perceived control may lead to higher self-disclosure, even in situations of higher objective risks (Chapter 2). I then examine some of the consequences that public disclosures entail in terms of impression formation and reputation building for the person who discloses information. It could be argued that online disclosures, even if embarrassing or incriminating, will soon stop representing diagnostic information about people – either because we will forget about them as time passes (Chapter 3), or because, as social norms about disclosure change, the majority of people will soon be tainted by embarrassing online records, which may contribute to render them more lenient towards others’ disclosures (Chapter 4). The results of studies in Chapters 3 and 4 challenge this view, and suggest that online disclosures may have a long lasting effect on impression formation.