Markus Tschersich

How to enhance Privacy and Identity Management for Mobile Communities: Approach and User driven Concepts of the PICOS Project

Mobility allows social communities to become a ubiquitous part of our daily lives. However, as users in such communities share huge amounts of personal data and contents, new challenges emerge with regard to privacy and trust. In this paper we motivate the necessity of advanced privacy enhancing concepts, especially for mobile communities and outline the approach of the PICOS project in order to elaborate such concepts. We explicate how we collected mobile community requirements and elaborated adequate concepts to address them. Finally, we conclude with details on how the concepts were prototypically implemented to demonstrate their feasibility, what distinguishes them from existing work, and how we intend to transfer the concepts to practice.

Privacy respecting targeted advertising for social networks

Online Social Networks form an increasingly important part of peoples lives. As mobile technologies improve accessibility, concerns about privacy and trust are more apparent as advertising becomes a critical component of most social networks economic model. In this paper we describe the PICOS projects research into privacy preserving advertising options for social networks. We introduce an architecture that includes new concepts and technologies specifically designed to improve privacy and trust as well as advertising opportunities within social networks.

Comparing the Configuration of Privacy Settings on Social Network Sites Based on Different Default Options

Current privacy research in the context of social network sites is based on the assumption that all entered personal information is public available by default. Literature from the fields of default settings and sharing behavior in social network sites lacks empirical insights how restrictive privacy default settings, that do not share personal information without the explicit decision of the users, influence their behavior. To gain empirical insight, a social network site privacy interface prototype with 14 different privacy settings was built to investigate in an experimental setting the influence of the preselected option on (1) the configuration behavior of the privacy settings, (2) the deviation from the default option, and (3) the size of deviation from the default option. In general, the results of our test show that users having restrictive privacy options as the preselected option significantly differ from users having permissive default privacy options because they are more influenced by the status quo bias and anchoring effect.

Pros and Cons of Privacy by Default: Investigating the Impact on Users and Providers of Social Network Sites

Based on actual experimental findings, we present a new line of argumentation about the chances, risks and effects of a Privacy by Default regulation for users and providers of Social Network Sites (SNS). We describe three important factors that have an impact on the utility provided by SNS and measure their change through opposing status quo. On empirical grounds, the results challenge the widely accepted assumption that restrictive default privacy settings cause overly negative consequences for providers.

On Gender Specific Perception of Data Sharing in Japan

Privacy and its protection is an important part of the culture in the USA and Europe. Literature in this field lacks empirical data from Japan. Thus, it is difficult– especially for foreign researchers – to understand the situation in Japan. To get a deeper understanding we examined the perception of a topic that is closely related to privacy: the perceived benefits of sharing data and the willingness to share in respect to the benefits for oneself, others and companies. We found a significant impact of the gender to each of the six analysed constructs.

Configuration Behavior of Restrictive Default Privacy Settings on Social Network Sites

Research about privacy in the context of social network sites has not addressed yet how users behave with restrictive default privacy settings. Literature about default settings and the sharing of personal information in social network sites lacks empirical insight into how restrictive default privacy settings influences the behavior of users. To gain empirical insight, a social network site privacy interface prototype was built to investigate the influence of default settings and interface style on the privacy configuration behavior of users. Results show configuration behavior differences between participants having restrictive or permissive privacy default settings. Further, interfaces with multiple pages of privacy settings induce participants to keep their default settings.

Design guidelines for mobile group recommender systems to handle inaccurate or missing location data

Todays group recommender systems do not consider unavailable, inaccessible, or incomplete user information of one ore more members within a group. This is a problem for mobile group recommender system, because changed user behaviour or technical limitations of mobile services let user may not be willing or able to disclose all information, which are part of a user profile in a mobile environment. For location information, as one of the most important type of user information for an ad-hoc mobile recommendation service, this can lead to inaccurate, or missing location information. Inaccurate or missing location information has an impact on different parts of building group recommendations. This impact reduces the quality of recommendations, which is a key-challenge of recommender systems. Therefore, design guidelines are needed to address the problem of missing or inaccurate location information in mobile group recommender systems. This work describes the approach of building and validating those design guidelines and gives a first idea of impacts.

Enhanced Privacy and Identity Management for Community Services - Demo of the PICOS Project

As online communities get increasingly mobile, enabling new location based community services, including privacy and trust for their users gets more important. Within the PICOS project we investigated and elaborated innovative concepts to improve the privacy of users within mobile communities based on three exemplary communities.