A primary concern of previous researchers in areas involving collaborative work has been providing users privacy and control over how the data collected from them is used by others.[14][5] ``A significant segment of the population wants to protect the privacy of any information related to its demographics, and its interests.''[17]
Specific to this project, we assume that there is a large class of users who would be willing to vote for or against articles, but for a multitude of reasons might not want others to find out how they have voted. For these users the collaborative system should provide a level of anonymity at least as good as the current Net News system. Net News by default maintains extensive logs of which articles have been requested by which machines - these logs being useful for managing the system. Someone with sufficient access to either these logs or users' accounts could piece together an accurate picture of what newsgroups and articles a user reads. For our system to provide a level of anonymity akin to Net News means that with sufficient sifting of the system logs it would be possible to find out which users read and voted on which articles, but the voting information is not easily available to anyone but a dedicated person with access to the logs.
Collaborative information contributed anonymously is useful for creating net wide summaries of the interest in particular articles. It is these summaries that will be available to help guide exploratory users. We assume, however, that vote information will be much more useful for collaborative filtering if the information is labeled with the name of the person it came from. Further, this type of identified information will have to be available in order to provide custom moderation of newsgroups.
In our design we provide users with methods of casting votes anonymously or of casting identifiable votes. The users also have indirect control over who can access their identified votes. By supporting the extreme positions, we believe we provide everyone a means of participation with which that they will feel comfortable.