Christian Matyas

Leibniz Institute for Educational Trajectories · Software Development

Recommender systems solve an information filtering task. They suggest data objects that seem likely to be relevant to the user based upon previous choices that this user has made. A geographic recommender system recommends items from a library of georeferenced objects such as photographs of touristic sites. A widely-used approach to recommending co...

The traditional, expert-based process of knowledge acquisition is known to be both slow and costly. With the advent of theWeb 2.0, community-based approaches have appeared. These promise a similar or even higher level of information quantity by using the collaborative work of voluntary contributors. Yet, the community-driven approach yields new pro...

We ask whether the photographs published in web-based image collections do represent different conceptualizations of a city. We present a method for gather-ing and analyzing a data set of more than 12.000 images from Amsterdam, Bamberg, Cardiff, and Dublin. A measure for the popularity of a location in a city is described. The analysis of the data...

The games with a purpose paradigm proposed by Luis von Ahn [9] is a new approach for game design where useful but boring tasks, like labeling a random image found in the web, are packed within a game to make them entertaining. But there are not only large numbers of internet users that can be used as voluntary data producers but legions of mobile d...