The Web form is the primary mechanism for collecting personal information.
Web users have been typing data into Web forms since they were added to the HTML standard in 1995. More than fifteen years later, the Web form remains the primary mechanism to collect personal data from individuals on the Web. We explore the way Web users interact with Web forms, how and which data they type in, and the interplay of optional fields and incentives. Our studies cover privacy concerns, time and effort, and the role of browser.
Relatively little is known about the behaviour and privacy attitudes of individuals when completing Web forms as part of completing a purchase or other commercial transaction on the Internet.
Our research done so far (Preibusch, Krol, Beresford, 2012) indicates that consumers regularly provide more data than required. In a field experiment, we recruited 1500 Web users to complete a form asking for ten items of identity and profile information of varying levels of sensitivity. We manipulated the number of mandatory fields (none vs. two) and the compensation for participation ($0.25 vs. $0.50) to quantify the extent of over-disclosure, the motives behind it, and the resulting costs and privacy invasion. We benchmarked the efficiency of compulsion and incentives in soliciting data against voluntary disclosure alone.
We observed a high prevalence of deliberate and unpaid over-disclosure of data. Participants regularly completed more form fields than required, or provided more details than requested. Through careful experimental design, we verified that participants understood that additional data disclosure was voluntary, and the information provided was considered sensitive. In our experiment, we found that making some fields mandatory jeopardised voluntary disclosure for the remaining optional fields. Conversely, monetary incentives for disclosing those same fields yielded positive spill-over by increasing revelation ratios for other optional fields. We discuss the implications for commercial Website operators, regulators, privacy-enhancing browser standards, and further experimental research in privacy economics.