Misperceptions of Uncertainty and Their Applications to Prevention

This thesis studies how people misperceive risk and uncertainty, and how this cognitive bias affects individuals' preventive actions.
Chapter 1, in a lab experiment, shows that how we present rare events affects how big people perceive those events. I show by means of a lab experiment that people perceive rare events bigger than what they actually are when those events are presented to them separately rather than all together.
Chapter 2 shows theoretically that it is actually the same phenomenon that makes people both overinsure and prevent little, namely probability weighting.
Chapter 3, with an application to cybersecurity, analyses an intervention aiming at increasing prevention at the organizational level in a field experiment. I test whether communicating information in a more effective way or letting employees experience a simulated phishing attack help to reduce falling for phishing attacks.
Chapter 4 deals with the issue that people’s judgements of risk might differ in different contexts. In a lab experiment, it shows that sexual context has an impact on ambiguity attitudes.