Patil and Kobsa interviewed seven participants on the privacy issues involved in IM . Häkkilä and Chatfield surveyed people in two different locales (Finland and Australia) about SMS messaging practices and privacy expectations of the medium . In both studies, the interviewees were very familiar with the domain being probed and were able to reflect on their behaviors and expectations, thus making them “expert informants.” Results showed that the mobile device was perceived as a “private object” and that a strong etiquette protecting the confidentiality of voice and especially text communication existed within the social group (e.g., interviewees would not pick up others’ phone calls, and expected the recipient of their text messages to preserve confidentiality). Häkkilä and Chatfield note that the selection of communication medium (SMS over voice) was influenced by confidentiality considerations. For example, SMS was considered more discreet than voice.
Grinter and Palen also studied teens’ use of IM and SMS . Like Häkkilä and Chatfield, Grinter and Palen found that the selection of the communication medium was based on privacy considerations (e.g., leaving no written trace) as well as convenience and availability. Specifically, Grinter and Palen showed how interviewees used the different features of IM to control access to themselves. At the same time, IM allowed users to keep a connection with their social group and to carve a private space in the household where they were unlikely to be overheard . Grinter and Palen asked questions about privacy as part of a broad interview about usage patterns and social context, which we believe is conductive to balanced and realistic results. Grinter and Palen noticed that different members of an outwardly “homogeneous” demographic—teens—report very different behaviors in terms of privacy, which warns against standard “common sense” assumptions about privacy expectations and preferences. A similar observation was made by Iachello et al.  in relation to inter-family use of mobile person finders.
Privacy also emerged as a fundamental component in two ethnographic studies of teens’ use of SMS, by Ito and Ling respectively [162, 201]. While these studies were not specifically designed to probe privacy, they exposed the relationship between privacy, group communication, accessibility, and familial power structures. Similar to Grinter and Palen, both Ito and Ling reported that the unobtrusive qualities of text messaging allowed teenagers to be connected with their social milieu even in situations where an open phone conversation would be inappropriate, such as a family dinner. They also discovered that environmental privacy (e.g., not interrupting or disturbing the physical environment) is an important aspect of communications for these teens.
The issues of environmental privacy and availability to communication can be extended to the sharing of other types of personal information with immediate relations. For example, Olson et al. probed information sharing practices in interpersonal settings . They surveyed the propensity to share information such as availability to communication, contact information, and personal communication preferences with other people. Olson et al. identified clusters, based on the type of information respondents would share and the recipient of the information (i.e., family and friends, close colleagues, remote colleagues, and others).
Expectedly, Olson et al.’s study showed that individuals indicated that they would share more sensitive information with closer acquaintances. It should be noted that Olson et
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