The systematic analysis of customer behavior with the help of spatial data mining is based on detailed usage information from individual customers. This is interesting from technology as well as from marketing side.  But when collecting, storing, and using personal data, network operators must exercise great care to ­determine the implications for data protection. The network operation not only has to fulfill the corresponding laws and ­regulations, but he also has to inform customers about ­potential data protection problems of new technologies and he has to ­provide the appropriate mechanisms to protect privacy.

How much do you want to reveal about yourself?

In his seminal work, Privacy and Freedom, Alan Westin ­defines privacy as a person’s ability to control where and to what extent his or her personal information is distributed and who ­ultimately has access to it. The wider the circle of distribution of the data, the greater the transparency of the person with respect to others, of course. This can be called “personal transparency”.

Another form of transparency is created with respect to the use of the collected data. This “data usage transparency” increases as a person learns more and more details about who uses his or her personal data and when for what purposes. There are advantages and disadvantages for both types of transparency.

Headhunters are using online resources more and more often when recruiting potential specialists and managers, so the more informative and transparent a person’s online profile is, the ­greater are his or her chances for climbing the career ladder. ­Online communities coalesce around highly specialized topics such as rare diseases and offer valuable assistance. The more ­precisely you describe your individual position the more specific the aid can be.

Unfortunately, not everyone who goes online has altruistic ­motives; there are also individuals and organizations pursuing criminal intentions. If enough personal information is available, someone may steal your identity to obtain financial benefits or confidential information or to reach a position of power. A bank might use personal and correlated data to decide on whether to give out a loan or not.  It may well refuse a loan owing to private data like the applicant’s familial circumstances, hobbies, or place of residence in a disadvantaged neighborhood. Employers are using personal and private information from applicants more and more frequently when they make decisions about hiring or promoting personnel. School children today are subject to extensive “online mobbing” made possible by the availability of personal data. Finally, information, once it has been placed online, remains there in the same form forever, even if a person has in the meantime developed in completely different directions. As a consequence, information may in part no longer be relevant or even present the wrong image of a person. If this obsolete “online picture” is then used as the basis for decisions, it may well have negative consequences.