The effect of privacy salience on end-user behaviour : an experimental approach based on the theory of planned behaviour

End-User privacy concerns surrounding use of Social Networks present new and complex problems for research. Specifically, a phenomenon known as “the Privacy Paradox” has been observed where end-users stated concerns, attitudes and intended behaviour are not consistent with the actual behaviour within the network. Numerous causes have been proposed as potentially being the root of the problem of this paradoxical phenomenon including a lack of user awareness of privacy issues, a low level skill in using technology or a lack of privacy salience within the social network itself. However, the role of the User Interface (UI) in contributing to, and potentially providing a solution to, poor privacy behaviour is under-explored. A potentially fruitful avenue of enquiry given that behaviour is considered to be a reaction to environmental stimulus and the UI provides the environment within which the user is interacting. This thesis implements a two phase approach to furthering understanding of privacy behaviour in social networks. First, a survey is implemented exploring the relationship of concepts within the privacy paradox identifying that users stated needs are not being met by their observable behaviour. Secondly, two experiments are implemented in order to explore this behaviour as an interaction with the network; these questions are answered to build a social network profile and can be grouped according to their potential sensitivity. A model of social psychology, the Theory of Planned Behaviour (TPB), is used to develop such experiments in order to examine the cognition behind these interactions. Each of the salient influencers defined by the TPB is used to inform a series of UI treatments and form the basis for experiment groups. An initial experiment explores the method and is used to inform the design of the second, which also introduces a factorial design to explore the relationships between treatments. These experiments show that participants within the treatment groups disclose less information than the control, with statistical significance. Within the first experiment this non-disclosure took place across all questions sensitivities, possibly due to limitations in the experimental method. However, participants in experiment two appear far more selective in their disclosure, choosing not to answer more sensitive questions suggesting that they thought of their privacy while interacting with the system. Findings within this thesis suggest that the UI plays an important role in influencing end-user behaviour as it can inform the context of the interaction as it happens.