Clemens Drews

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We present a new algorithm for inferring the home locations of Twitter users at different granularities, such as city, state, or time zone, using the content of their tweets and their tweeting behavior. Unlike existing approaches, our algo rithm uses an ensemble of statistical and heuristic classifiers to predict locations. We find that a hierarchical(More)
Large displays have several natural affordances that can simplify small group collaborative work. They are large enough to hold multiple work areas, they are easy to see and can be manipulated directly via touch. When placed into group and public spaces, such displays create pervasively available working surfaces for lightweight, temporary walkup use. The(More)
ActionShot is an integrated web browser tool that creates a fine-grained history of users' browsing activities by continually recording their browsing actions at the level of interactions, such as button clicks and entries into form fields. ActionShot provides interfaces to facilitate browsing and searching through this history, sharing portions of the(More)
A. Cozzi S. Farrell T. Lau B. A. Smith C. Drews J. Lin B. Stachel T. P. Moran In this paper, we present a new method for organizing collaborative work. This method is based on the concept of ‘‘activities,’’ defined here as high-level structured representations of the people, artifacts, and processes involved in work and their relationships. We show how(More)
Millions of people express themselves on public social media, such as Twitter. Through their posts, these people may reveal themselves as potentially valuable sources of information. For example, real-time information about an event might be collected through asking questions of people who tweet about being at the event location. In this paper, we explore(More)
We present an intelligent, crowd-powered information collection system that automatically identifies and asks targeted strangers on Twitter for desired information (e.g., current wait time at a nightclub). Our work includes three parts. First, we identify a set of features that characterize one's willingness and readiness to respond based on their exhibited(More)
We present an empirical study of teams that revealed the amount of extraneous individual work needed to enable collaboration: finding references to other people, finding files to attach to email, managing incoming email attachments, managing the variety of files used in shared activities, and tracking what work is owed to others. Much of this work involves(More)