We present and analyze several gaze-based graphical password schemes based on recall and cued-recall of grid points; eye-trackers are used to record user’s gazes, which can prevent shoulder-surfing and may be suitable for users with disabilities. Our 22-subject study observes that success rate and entry time for the grid-based schemes we consider are comparable to other gaze-based graphical pas...

Certain privacy principles have been established by industry, (e.g. USCAM, 2006). Over the past two years, we have been trying to understand whether such principles reflect the concerns of the ordinary citizen. We have developed a method of enquiry which displays a rich context to the user in order to elicit more detailed information about those privacy factors that underpin our acceptance of u...

This paper presents the results of our concept annotation tool in the ImageCLEF 2012 Photo Annotation Task. Our approach is based only on textual features, in particular collaborative user tags. It faces some of the challenges of using user-generated terms, such as noise and incompleteness. The first one is supported by a multi-phase filtering procedure that amends misspelled tags and considers...

In the last years, social networking sites (SNSs) have enjoyed an undeniable success. Those web platforms have huge quantities of active users sharing lots of information everyday. Usually, user-generated content may be almost innocuous, however, some studies have shown that it may also contain very sensitive personal data. This situation may pose a serious privacy threat to the users due to th...

Users looking for books online are confronted with both professional meta-data and user-generated content. The goal of the Interactive Social Book Search Track was to investigate how users used these two sources of information, when looking for books in a leisure context. To this end, participants recruited by seven teams performed two main tasks and one optional task using a user-interface tha...

Online reviews of services and products are increasingly posted via mobile devices rather than a website. Our research shows that opinions posted via mobile devices are more timely, shorter, more “to the point” and more negative than web reviews. Moreover, more positive reviews are on average shorter than negative reviews. We arrived at these conclusions by analyzing all reviews posted in 2012 ...

As they relate to user-generated content on the internet, civic engagement and psychological empowerment have received significant interest in recent years. While past studies have examined online civic participation and political empowerment, the way in which civic engagement offline and content generation online are related to psychological empowerment has not been thoroughly explored. The pu...

In order to understand the effects of interaction on User Experience with a range of MP3 players, we used a Personal Construct Theory approach (Kelly 1955) to elicit users’ anticipations and interpretations of their experience with technology. Sixteen participants rated four different MP3 players on a variety of user-generated constructs in the form of rating scales before and after interaction...

User-generated content in social media can offer valuable insights into local trends, events, and topics of interest. However, navigating through the vast amounts of posts either to retrieve certain pieces of information or to obtain an overview of the existing content, is often a challenging and overwhelming task. In this work, we present μTOP, a system for detecting and summarizing locally tr...