receiving hate mail. Futility risks, instead, mean that the effort that users put in participating in online social interaction services does not bring the intended ...
IADIS International Conference ICT, Society and Human Beings 2008
PRIVACY REGULATION IN ONLINE SOCIAL INTERACTION Jaakko T. Lehikoinen Nokia Research P.O. Box 1000, FIN-33721 Tampere, Finland
Thomas Olsson, Hannu Toivola Tampere University of Technology P.O.Box 589, FIN-33101Tampere, Finland
ABSTRACT Social online services play significant role in people’s social interaction practices. Social networking services, like Facebook or MySpace, instant messaging services, blogs, and microblogs, like Jaiku or Twitter provide motivating ways to interact and stay in touch with others. However, when new services and communication possibilities are introduced to the masses, privacy regulation mechanisms are not following the development. Controlling presentation of self in online context is not easy and consequences of information disclosure are not necessarily visible or even thought. Often, users of these services can only decide whether to share information to everyone using the same service or share it only with the selected people. We conducted a qualitative study to investigate privacy regulation practices and factors affecting information disclosure in people’s daily social online interaction. We use the Privacy Regulation Model as a basis of our study. Not surprisingly, privacy settings that these services provide are rarely used and the participants relied mainly on their own judgment in what information to share and how. Adjusting the level of anonymity, selecting appropriate communication channel based on sensitivity of information, and editing content before sharing, were used to regulate the amount and depth of information that was disclosed. We also propose extension to the Privacy Regulation Model as we found that culture of community and competence are significant factors affecting information disclosure in social online services. Understanding current practices of regulating privacy in online social interaction facilitates service designers and providers to develop more relevant and reliable means to interact with others. KEYWORDS Privacy, privacy regulation, social interaction, online communities.
1. INTRODUCTION Privacy has been a topical issue with regard to online communities, such as Facebook and MySpace. Discussion in public media has mostly concerned cases where users’ personal information has been accessed without permission and distributed, or it has accidentally been leaked, to third parties. This is, of course, something that needs attention and the problems need to be solved, the sooner the better. However, even if the discussion of the above mentioned risks and invasions of privacy are the most visible and, at least in short-term, the most crucial ones, privacy is much more than that. Privacy is a complex term and next we present alternative ways to define it. Schoeman (1992) has identified three most typical definitions as follows. First, privacy can be understood as the measure of control an individual has over information about himself, intimacies of personal identity and/or who has sensory access to him. Second, privacy can be understood as a state or condition of limited access to a person. Third, privacy can be defined as a claim of individuals to decide about dissemination of information concerning themselves. Westin (1970), whose definition is often used in literature understand privacy as follows: “Privacy is the claim of individuals to determine for themselves when, how and to what extend information about themselves is communicated to others.” A common denominator for these definitions is emphasis on individual’s control. Altman (1975) understands privacy in relation to social environment and interaction. According to him, privacy is dialectic and dynamic boundary regulation process that takes place in dialog
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with others. People have various mechanisms to regulate these boundaries. According to Altman (1975), the following privacy regulation mechanisms are used in face-to-face setting: verbal behavior (content of speech), paraverbal behavior (voice intensity), personal spacing (distance from others), and territorial responses (personalizing and controlling geographical areas and objects). Depending on the situation, an individual uses these mechanisms in different ways. Further, one mechanism may substitute the other according to changes in the social context. Altman also states that behavior may change in a course of time, thus the process of privacy regulation is dynamic. Lehikoinen et al. (2007) extends Altman’s theory to cover social interaction in ubicomp setting. They introduce privacy regulation mechanisms that are relevant in mediated communication as follows: management of visibility, management of access rights, various filtering rules, context awareness, personal spacing, which means hiding a device used for communication or adjusting brightness of display or volume. All in all, Altman’s way of understanding privacy with the needed extensions is fruitful when investigating privacy regulation behaviors in social online services due to the fact that it looks at privacy as dynamic and dialectic process rather than only individual control or hiding activity. Social interaction is dialectic also in online context. As people’s social interaction is increasingly taking place in online setting, both daily communication and privacy regulation practices are in a rapid process of change. Social online services support only a limited set of privacy regulation mechanisms, and generally, most of them are far too laborious to use for many, and thus they are often left untouched (see e.g. Gross et al. (2005), DiMicco and Millen (2007)). These kinds of observations lead us to investigate privacy regulation in online social interaction more broadly. Online social interaction can refer to various services and media that contain numerous motivating possibilities to communicate with others. In this paper, we concentrate on social networking services, blogs, discussion forums, and instant messaging services. Modes of social interaction in these media may contain for instance, conversation, both asynchronous (e.g. messages in social networking services) and synchronous (instant messaging services) messaging, blogging, micro-blogging, recommendations, and sharing media content like images, videos and music. Micro-blogging means here status updates that can be either manual or automatic and include e.g. text, images, or location, music that is currently listened, and mood. Also poking belongs to this category. Today, people’s daily communication is not focused only on one media but is mixed and even parallel use of several media is commonplace. We conducted a qualitative study to reveal current privacy regulation mechanisms and factors affecting information disclosure in services enabling versatile means for social interaction. We want to draw an overall view on privacy regulation in online social interaction rather than focusing only on some of the services. Obviously, this increases the research challenge, but is the only way to find privacy regulation practices that are not dependent on a single social online service. The main motivation for our research is a lack of studies on privacy regulation that would have considered the fact that people are using various social online services in their daily communication practices. Understanding these aspects of social interaction facilitate service designers and providers to develop more relevant and reliable means to regulate sharing personal information, communicate with friends, share other digital content, such as images and videos, and present oneself in these services. Further, understanding social interaction in this context builds theory on dynamics of social interaction in the context where it is taking place equally in digital and physical worlds. The rest of the paper is structured as follows. Next, the related work and our approach to privacy regulation are described. The results section presents generic user practices and principles in online social interaction, factors affecting information disclosure, and privacy regulation mechanisms that are used in online social interaction. Finally, we conclude the paper by summarizing the main results, discussing about future research needs, and indicating limitations and usefulness of our contribution.
2. PREVIOUS WORK AND OUR APPROACH Several studies in the fields of HCI and ubicomp have stated that privacy, especially lack of it, is a real problem in computer mediated communication. (see e.g. Bellotti & Sellen (1993), Soppera and Burdridge (2004), and Langheinrich (2002)). Capabilities of computational systems to record conversations and distribute them further to third parties are the main factors increasing the risks of invasion of privacy. (Palen
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and Dourish 2003). Regardless of these risks, people use various communication tools continuously in their daily lives. People’s practices with regard to privacy regulation are versatile. Dourish et al. (2004) conducted qualitative study on experience and practice of security in work context. They found that security tools are often left alone due to numerous usability problems they contain. Instead, the study participants used to, for instance, “encrypt” their emails by using such titles that the intended recipients understood in the given context. This is an example of such privacy regulation mechanism that is not supported by the system but is still used to decrease the risk of information leaks. Privacy attitudes and self-expression practices in online social online services are studied as well. Acquisti et al. (2006) found in their quantitative study that Facebook users are concerned about their privacy but they still reveal great amounts of personal information. Users manage this concern by trusting their ability to control the information they disclose in Facebook. Further, they found that the users are not fully aware of how they are seen by the others in Facebook and what the actual size of the final audience is (c.f. Palen and Dourish 2003). An interesting observation was also that privacy attitudes affected only decision on joining the network, but after joining the difference between the respondents about information disclosure practices were only marginal. Further, DiMicco and Millen (2007) investigated how people manage selfpresentation in Facebook. They revealed for example that users have a common problem of managing multiple user profiles or identities in online setting and stated that better authoring tools for supporting more effective content management and access rights management are needed. Several studies present privacy frameworks, models, and design principles from various perspectives, like multimedia communication (e.g. Adams, 1999), or location awareness (e.g. Smith et al. 2005). One of the earlier studies by Bellotti and Sellen (1993) discusses about the importance of user control and feedback. Their design framework proposes that a system should provide control and feedback for at least the following system and user behaviors: capture (information that is acquired), construction (how the information is processed), accessibility (who gets access to the information), and purposes (what is the information used for). Lederer et al. (2004) summarizes many of the earlier design principles well in categories of understanding and action, which means privacy regulation mechanisms. Understanding refers to both making clear for the user both potential and actual information flow. Users need to be aware of what information is possible to disclose to whom and what information is actually being disclosed to whom. Action refers to three issues; first, making privacy practices as a normal activity with the system, second, providing mechanism for halting and resuming disclosure, and third, not inhibit the users to transfer established social practice to emerging technologies. When looking at most of the social online services, a question of how well these guidelines are followed raises easily. For instance, privacy settings cannot be seen as natural practice with the system. Instead, they are exactly “emphasizing configuration over action” which Lederer et al. (2004) have pointed out as one of the pitfalls of designing privacy regulation mechanisms. To conclude, we need to continue research on privacy perception and current practices in order to be able to design more relevant and valuable privacy regulation mechanisms for social online services. The fact that people are using several social online services increase the importance of better understanding what kinds of privacy regulation mechanisms would be used.
2.1 Our Approach We are interested in overall use of privacy regulation mechanisms across various social online services. This means that we aim to gain understanding social interaction in environment where several media is used e.g. for staying in touch with friends and communicating with colleagues, rather than focusing on one specific media. The latter has been much more common approach in previous research. We use the Privacy Regulation Model (Lehikoinen, 2007) as theoretical and methodological approach in our study. It was chosen due to the fact that it is designed to facilitate analyzing and designing privacy aspects of interactive systems. The Privacy Regulation Model consists of five factors that affect people’s information disclosure practices. These factors are content, relationship, relevance, context of use and risks. These are shortly described as follows. Content is the information that users disclose and its sensitivity determines people’s willingness to disclose information. Relationship, like trust, between users disclosing information and the recipient(s) is another factor affecting information disclosure. According the Privacy Regulation Model, anonymity and
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pseudonymity play significant roles in information disclosure as characteristics of relationship. Relevance relates to the first two factors; intended content should be disclosed to intended recipients. The user should be able to decide what information, to what extent, and to whom it will be disclosed. Risk of information misuse refers to perceived possibilities to use the information for other than originally intended and harmful purposes. Context of use is the final relevant element having an impact on disclosure of information. Eavesdropping (heard or seen) is a considerable factor affecting privacy perception. The Privacy Regulation Model does not specify the dynamics between these five factors, as the information disclosure is often unconscious and factors are somewhat overlapping (Lehikoinen 2007). Our research questions are as follows: - What are factors affecting information disclosure in social online services (in addition to ones presented in the Privacy Regulation Model)? - What kinds of privacy regulation mechanism are used in online social interaction? Answering these questions sheds new light on online social interaction and thus, extends and complements current knowledge on it.
3. STUDY SETUP AND METHODOLOGY We conducted a set of qualitative interviews to answer our research questions. Qualitative approach was considered more appropriate than quantitative due to the fact that the objective was to reveal practices that we were not aware of rather than presenting quantitative results to specific and well established research problems. By doing this, we were able to gain more information by going deeper into issues of interest with small number of people than conducting a large scale quantitative analysis. In total, nine semi-structured thematic interviews were conducted. We had six male and three female participants, and their ages varied between 23 and 31. Seven of the participants used online services several hours a day, and therefore they were experienced in privacy regulation as well. Further, they were technically apt. The other two participants had used social online services less than one year. All the participants can be considered as social or very social, but the readiness to share personal information in social online services varied greatly. Most of the seven active participants were also relatively well educated, which also affected their knowledge and understanding of privacy related issues. We set experience of either using Facebook or writing a blog as recruiting criteria for the participants. Consequently, the participants had at least some experience on using Facebook, and some of them had also written blogs. In addition to these, the participants had varying experiences with, for instance, blogs, shared photo galleries and instant messaging. Interviews consisted of two main themes. First, privacy regulation mechanisms that the participants used and the reasons for using them were discussed. Second, perceived risks of sharing personal information in social online services, as well as participant’s thoughts on probability and severity of these risks were discussed. The semi-structured interview was based on the five elements of the Privacy Regulation Model to cover the various aspects of privacy. Moreover, the factors of the model also served as inspiration and stimuli for further discussion on factors the model possibly does not consider. Interviews were conducted using two interviewers. One of the interviewers acted as a moderator asking questions and steering the conversation in the desired direction while the other interviewer wrote down observations and double-checked the question list to ensure that all topics were handled. Interviews were recorded with the approval of the interviewees for the analysis purposes.
4. RESULTS In this section we present the main results of the study including, factors affecting information disclosure, and privacy regulation mechanisms in online social interaction. But first, we will describe typical uses of these services amongst our participants, their thoughts on information disclosure, and risks that they see in online social interaction. By doing this, we want to contextualize more specific privacy related findings and make them more understandable for the readers.
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Our participants used several communication channels for various purposes in online context. Socializing and maintaining awareness of friends’ statuses were the main motivations of use. Social networking services, mainly Facebook, were continuously open and thus the participants were well aware of what is happening within their social network. Instant messaging services were most often used for one-to-one interaction and sometimes various channels were used in parallel. An interesting finding was that communication usually took place with same friends via several social online services. These services were used both at home and at school or work. Two main principles with regard to regulating sharing of personal information were common to all participants. The first one was using common sense in deciding on what information to disclose keeping in mind that eventually anyone can retrieve the information later on. One participant put it as follows:” Don’t share anything you don’t want to be publicly known”. This quote highlights the fact that participants were aware of a possibility that everything that is published in the web can be recorded and further distributed. The second principle was valuing other’s privacy. This well known principle from, especially Christian, ethics was stated by one participant:” Treat others in a way you would like to be treated”. Since usage of social online services is very open and lightly moderated, people can say more or less what they want. This, together with the notion of speed and possible extent of information distribution, increased the need of being very careful of disclosing information related to others. Generally, protection of other’s privacy was seen as an essential norm as people can only control of what information they disclose but not have any concrete means to affect what others are sharing. By following this norm, the participants wanted to affect others’ decision to do the same. Here, Altman’s (1975) notion of dialectic nature of privacy regulation becomes concrete in online social interaction. Our participants were interested in their public image. Social online services often include a profile page where users can describe themselves. Real name, nickname, email address, hobbies, political views, religion, movie and music taste are examples of personal information that profile page may contain. According to the participants, their profiles contained such information that they considered being fairly public. Some of the participants said that they wanted to make themselves look interesting for the others but they still reported that they try to keep the profile pages minimalist. Most of the participants stated that they avoided publishing personal facts, like address, email address, phone number, or occupation that would have exposed them to physical or economical risks. Instead, according to some participants, their social activity in these services, i.e. postings and messages they write, music they listen, and comments they make, describe their personality much better than a generic profile page. The most probable risks that the participants brought out were social risks and futility risks1. In addition, there were common but minor concerns of possibility that service providers might sell personal information for marketing purposes. In the case of Facebook, some participants brought out their concern of open application development. They said that it increases the uncertainty related to controlling personal information sharing.
4.1 Factors Affecting Information Disclosure The Privacy Regulation Model presents five factors affecting information disclosure in mediated social interaction. In this section, we briefly discuss the meaning these factors and bring out two additional factors that are, based on our findings, significant in online social interaction. Relevance was clearly the most dominant factor affecting information disclosure. The participants brought out that the information they share needs to be interesting, meaningful, and/or purposeful for the others. Here, avoiding to share information of someone else if it was not important belongs to the Relevance category. Relevance seemed to override the content, relationship, context and risk factors that, however, were evidently relevant as well. The perceived risks made most of the participants to avoid publishing any such facts that might lead to e.g. negative economical or physical consequences, as discussed earlier. Social security number, home address, and credit card numbers were frequently mentioned as these kinds of facts. Overall, the perceived benefits and motivation for online social interaction were more dominant factors 1 Here, social risks refer to negative social implications that can be caused by, for instance, a wall posting in Facebook, which leads into receiving hate mail. Futility risks, instead, mean that the effort that users put in participating in online social interaction services does not bring the intended benefit, e.g. they might lose the text that they have written, or alternatively no-one responds their postings.
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affecting information disclosure than perceived risks. The balance between Relevance and Risks seemed to shape the decisions on information disclosure. In addition to the factors presented in the Privacy Regulation Model we found two factors more, which significantly affected information disclosure in online social interaction. These are culture of community and competence. By culture of community we mean values, norms and the type and style of social interaction that occurs within one social online service, like in Facebook. We found evidence that generally very open culture prompted openness, whereas being reserved decreased openness and thus willingness to disclose information. For example, ways to use status updates, i.e. information on what users are currently doing, how they are feeling, where they are, etc. varied remarkably from one service to another. Some of the services that our participants used had a culture where people updated their status information frequently and openly, whereas in some other services this feature was hardly used at all. For instance, updating status information frequently and openly, constructed a culture where information rich status updates were expected, and thus it became a norm in that particular service (amongst a particular sub-community). Naturally, this norm set expectations for people belonging into community and therefore, it also affected their ways to interact with others and disclose personal information. These kinds of cultural differences were clearly seen in cases where participants were active in using more than one social online service. Competence means skills in using the tools for interacting with others that a service provides and awareness of culture in the context where social interaction is taking place. Some of the participants reported that experience diminishes the effects of social pressure and over enthusiasm that, in some cases, occur in the very first days of using a service and drives them to disclose more information than intended. Generally, competence means that users are aware of, and can utilize both various communication and privacy regulation tools to adjust the level of social interaction.
4.2 Privacy Regulation Mechanism When looking at privacy regulation in online social interaction across various services, we can distinguish both service dependent and service independent privacy regulation mechanisms. Service dependent mechanisms are features that services provide, such as privacy settings in Facebook. Service independent mechanisms are tools that are not provided by these services. For example, editing an image with image editing software before publishing it belongs to this category. Further, there are such privacy regulation mechanisms that are not supported by any tools, and are controlled only by cognitive processes. An example of this is deciding what kind of an image to publish in a profile page. The most obvious privacy regulation mechanism is selection of content, i.e. decision on what to write and what images and videos to share. Especially, asynchronous communication means, like discussions and messaging in social networking services as well as blogs, provide good tools for presenting oneself, since users can prepare the text before publishing it. Further, some of the participants pointed out that the style, i.e. how things are said, is equally important. For example, one of the participants used literature language in order to make his postings look like more professional. Another obvious set of privacy regulation mechanisms is service dependent settings. The participant’s practices with regard to using these settings varied to some extent. Some used the basic levels of access rights for content, which were, private, selection of people, and public. Those who used these settings reported that they are relevant whereas those who did not use them thought that they are more or less futile. However, all said that these kinds of settings are far too laborious to use. One of the participants presented a wish to have service independent privacy settings that can be set as default when starting to use new service. This stresses the need for service independent tools that support social interaction across various services. Selecting media can be seen as a privacy regulation mechanism when it is done to inhibit possible information leaks. We found that some of participants selected media according to the need for communication as well as sensitivity of information they were about to share. For instance, many selected instant messaging service when they wanted to have more private conversation with their friend or friends. This was done even if the social networking service provided means for person-to-person communication. Some of the participants pointed out that social networking services are not perceived as reliable and suitable for private conversation as instant messaging services. It seems that none of the currently available social
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online services provide appropriate means enough for the myriad of social interaction situations and needs people have. Adjusting the level of anonymity is an important privacy regulation mechanism. In practice, it means decision of being fully anonymous (if the service allows), using nicknames or presenting oneself with real name. The participants considered that use of a nickname is a good method to regulate privacy as it enabled friends to identify them whereas for strangers identifying is impossible or at least very laborious. Generally, usage of social online services starts to build up online social identity. Due to the fact that the participants used several services, they had challenges in managing their multiple identities. There were no independent tools for supporting this kind of practice and the main privacy regulation mechanism was consistent use of nicknames. Some of the participant emphasized the importance of presenting oneself consistently across the services, due to a fact that many of their friends used the same services. According to these participants, being inconsistent with self-expression may lead to unfavorable social consequences. As there were no tools to support behavior, some of the participants brought out the only thing they can do is to rely on their memory. However, as one of the participants brought out, sometimes using a nick that is not known by friends, and thus increasing the level of anonymity, is good. In these cases, the users do not want to reveal to their friends that they are using, or even visiting, some particular services, which might be morally or legally suspicious2. Most of the participants brought out that knowing how one is seen by others is important. They complained that the social online services do not provide appropriate means to check how others see them. Some used their own name or nickname as a keyword in web search for monitoring what information is available of them. Also these kinds of means are here understood as privacy regulation mechanisms. Protecting others’ privacy was common for all participants and some privacy regulation mechanisms were used especially for that purpose. For instance, when publishing images, some participants either blurred or removed other persons from them. Or, when other persons were referred in written text, they were identified only with nick names or with fist names in such a way that only the intended information receiver understood the people who were meant.
5. CONCLUDING REMARKS Understanding privacy in the context of online social interaction is crucial. People’s social interaction is increasingly taking place in the web and, at the same time people are becoming more aware of privacy related risks. These observations indicate that that there are clear needs and requirements for developing more relevant privacy regulation mechanisms. We conducted a qualitative study to better understand current practices in privacy regulation, perceived privacy and factors affecting information disclosure in online social interaction. Findings of our study have both practical and theoretical contributions. Practical contributions refer e.g. to findings related to lack of privacy regulation mechanisms and the notion of service independent mechanism that would be useful across various services, like in facilitating management of identity or usage of default privacy settings. These findings, together with points that Lederer et al. (2004) made about designing privacy practices as a normal activity with the system, bring out areas that the service developers and designers need to pay attention to when thinking about social online services of the future. The extension to the Privacy Regulation Model that we suggest is complementing theoretical understanding on privacy. Competence and the culture of a community were found significant factors affecting information disclosure. Further, dynamics between relevance and risks factors need to be further investigated, as we pointed out. The qualitative study presented here is gaining understanding on privacy with a special focus on privacy regulation in social online interaction. Our next step is to conduct a quantitative study to assess the importance and generality of the findings and reveal interrelations between the factors affecting information disclosure. Further, investigating each of the social interaction possibilities more deeply constructs more information about the current behavior and reveals important factors for designing means to regulate privacy in online 2
Another thing is then how much users’ anonymity should be protected if services are explicitly for illegal issues, like drugs.
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social interaction. It seems that the number of these possibilities is continuously increasing whereas privacy regulation mechanisms are not following the development. Therefore, paying close attention to social interaction practices as well as privacy regulation practices is important and will eventually shape the way people communicate with each other in the future.
ACKNOWLEDGEMENT The authors want to thank Juha Arrasvuori for his contribution to study design.
REFERENCES Acquisti, A. et al. 2006. Imagined Communities: Awareness, Information Sharing, and Privacy on the Facebook. 6th International Workshop, PET 2006, Cambridge, UK, pp 36-58. Adams A. 2000. Multimedia information changes the whole privacy ballgame. Proceedings of the Tenth Conference on Computers, Freedom and Privacy. Toronto, Ontario, Canada, pp 25-32. Altman, I. 1975. The Environment and Social Behavior. Brooks/Cole Publishing, Monterey, CA, USA. DiMicco, J. and Millen, R. 2007. Identity Management: Multiple Presentations of Self in Facebook. Proceedings of the International ACM SIGGROUP Conference on Supporting Group Work, Sanibel Island, Florida, USA. pp 383-386. Dourish, P. et al. 2004. Security in the Wild: User Strategies for Managing Security as an Everyday, Practical Problem. In Personal and Ubiquitous Computing, Vol 8, pp 391-401. Facebook. http://www.facebook.com/ Gross, R. et al. 2005. Information Revelation and Privacy in Online Social Networks. Proceedings of the 2005 ACM workshop on Privacy in the electronic society, Alexandria, VA, USA, pp 71-80. Langheinrich M. 2002. A Privacy Awareness System for Ubiquitous Computing Environments. Proceedings of UbiComp pp. 237-245 Lederer S. et al, 2004. Personal Privacy through Understanding and Action: Five Pitfalls for Designers. In Personal and Ubiquitous Computing, Vol. 8, pp 440-454. Lehikoinen J.T. et al., 2007 Understanding Privacy Regulation in Ubicomp Interactions. In Personal and Ubiquitous Computing, Online First. Lehikoinen J.T. 2008. ‘Theory and Application of the Privacy Regulation Model’ in Handbook of Research on User Interface Design and Evaluation for Mobile Technology, ed. Lumsden, J. Information Science Refernce, New York, USA, pp 863-876. MySpace. http://www.myspace.com/ Palen L. and Dourish, P. 2003. Unpacking “Privacy” for a Networked World. Proceedings of ACM CHI Conference on Human Factors in Computing Systems. (pp.129-136). Schoeman, FD. 1992. Privacy and social freedom. Cambridge: Cambridge University Press. Smith et al. 2005. ‘A Social Approach to Privacy in Location-Enhanced Computing’ in Privacy, Security and Trust within the Context of Pervasive Computing, ed. Robinson, P. Vol. 780, pp 157-167. Soppera and Burdridge. 2004. Maintaining privacy in pervasive computing – enabling acceptance of sensor-based services. BT Technology Journal. Vol. 22, No, 3, pp 106-118 Westin, A. 1970. Privacy and Freedom, (2nd ed.). Atheneum, New York, USA.
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