In this chapter, we differentiated between three categories of related work towards online privacy, and focused on the related work for PFA tools. We identified the shortcomings of current PFA tools and motivated our developing a PFA tool that helps OSN users both explore their egocentric networks and control information flow. We then looked into the related work on visualizations tools for data analytics and exploration for aggregate data transparency, and motivated our directions in developing relevant tools. Finally, we motivated our research effort in the field of data-visualization library design.
Part I
Online Social Privacy
Addressing Context Collision
Many people are on OSNs nowadays. A user’s network may contain hundreds to thousands of “friends”. Managing these online friends can be particularly difficult due to blurred boundaries between contexts of “conversations”. This phenomenon is called Context Collision. It becomes increasingly difficult for users to act (post, chat, share, like, etc.) the way they intend to, causing undesired consequences. One of the major negative consequences of Context Collision is unwanted exposure of private information. It concerns people’s social privacy on a micro-level where people conduct their daily online interactions. While the concept of Context Collision is straightforward to be understood, the concept of context itself is ambiguous. Indeed, all aspects of life can be the potential context in which a person interacts with others online. However, we argue that the most essential aspect of a so-called context is the “audience”, i.e. the people whom a person talks to or shares information with, and the initial categorization of the “audience” is the first step towards context recognition and construction. In this chapter, we address Context Collision by developing an interactive friend-grouping tool named FreeBu#1 for Facebook users.
3.1
What is Context Collision?
An OSN today can hold hundreds of millions of users. Facebook (www.facebook. com) has exceeded its “one billion users” mark [192]. Behavioural and sometimes very personal information of OSN users is uploaded and shared online daily, in large quantities and tremendous detail. While the availability of these data enables us to understand more about our societies, it also challenges us in
WHAT IS CONTEXT COLLISION? 33
effectively and efficiently processing large amounts of information, and managing our online personal content.
Context Collision or Context Collapse [29, 122, 140], is a widely discussed
phenomenon from the world of Online Social Networks (OSNs). Boyd [29] describes it as the lack of spatial, social, and temporal boundaries (in OSNs), making it difficult (for OSN users) to maintain distinct social contexts. More specifically, the requirement to present a verifiable, singular identity makes it impossible to differ self-presentation strategies, creating tension as diverse groups of people flock to social network sites [29, 122]. This phenomenon is exacerbated when more people become users of OSNs such as Facebook (www.facebook.com) and Google+ (www.plus.google.com). According to Facebook1, there are 1.49
billion monthly active users as of June 30, 2015.
“Context” is a multifaceted concept [48, 80]. We differentiate two characteristics of a given context: first, a context contains a group of people, and a particular role is expected from the person when he is within this context, to which we refer as the role-playing characteristic [147]; second, the people within the same context “are closely related to each other, in such a way that one would expect information about the user’s interactions with one of them to become known to the others” [42], to which we refer as the information-enclosing characteristic. Therefore, the information exchange between two people in the same context is usually more private than that in different contexts. Say a person has two contexts, one is at a company where he is an employee, the other is at home, where he is a husband. He plays two different roles within two different groups of people. The conversations between him and his spouse are private to his colleagues at work and the conversations between the person and his colleagues are also usually not expected to be heard by his spouse. Context Collision refers to the phenomenon that the boundaries among people are blurred, the contexts in which they reside become mixed.
In an offline environment it is not difficult to distinguish between different contexts, because most of the time we know what topics we can talk about, or how we should behave toward others within a specific group of people. However, in an online environment, due to the lack of a contextualization mechanism in OSNs, such discernment is weakened. Context Collision makes it difficult for a user to control the flow of his/her personal information in OSNs. Following the theoretical framework of Goffman [74], De Wolf and Pierson point out that there is a lack of alternation between the front and back stages in OSNs. The front stage is where a person puts on “shows”, a “polished” or “acted” self, to some extent, is presented to the “audience”. The back stage is where a person communicates more privately, within a smaller range of “audience” than in the
front stage. The alternation between the two stages is necessary in constructing a personal identity. But Context Collision weakens user’s ability to “act on stage” [184].
According to Lampe [110], the purpose of people using Facebook is primarily for maintaining their previous, offline relationships. As the PewInternet report
2 shows: an individual has met 89% of his/her Facebook friends more than
once offline. Research has indicated that, by publishing (personal) information, OSN users are engaged in Impression Management [169, 76, 191] and building Social Capital [49]. Impression Management refers to the process in which people attempt to influence the perceptions of other people about a person. Typically, this person is the user herself. Social Capital refers to the resources accumulated through the relationships among people [38].
With so many complex human activities conducted in OSNs, the default contact management options offered by OSNs are poor (we examine them in more detail in Section 3.2). Besides the default options, a user often follows two options. One is to simply address a specific group of friends while others also see the published information. Alternatively, to avoid unpleasant privacy breaches, the user applies the lowest denominator strategy [95] – to only post the information that is suitable for all of his/her friends. In the former, privacy suffers; in the latter, the user’s choices to realize different identities are constrained. To address
Context Collision, we built an FA tool that helps Facebook users manage their
contacts (i.e. friends).