Inst. Wirtschaftsinformatik und Quantitative Methoden

49 Items

Recent Submissions
An intelligent health assistant for migrants

Plumbaum, Till ; Narr, Sascha ; Schwartze, Veit ; Hopfgartner, Frank ; Albayrak, Sahin (2013)

Preventive health is becoming an increasingly important part of our society. In addition to improving people’s personal well being, another positive effect is the reduction of costs for medical treatments that put a high burden on individuals and health care providers. Despite these advantages, preventive health services are still not used at a desired level. This is especially true for people ...

Workshop on benchmarking adaptive retrieval and recommender systems - BARS 2013

Castells, Pablo ; Hopfgartner, Frank ; Said, Alan ; Lalmas, Mounia (2013)

Evaluating adaptive and personalized information retrieval techniques is known to be a difficult endeavor. The rapid evolution of novel technologies in this scope raises additional challenges that further stress the need for new evaluation approaches and methodologies. The BARS 2013 workshop seeks to provide a specific venue for work on novel, personalization-centric benchmarking approaches to ...

Detecting violent content in Hollywood movies by mid-level audio representations

Acar, Esra ; Hopfgartner, Frank ; Alyabrak, Sahin (2013)

Movie violent content detection e.g., for providing automated youth protection services is a valuable video content analysis functionality. Choosing discriminative features for the representation of video segments is a key issue in designing violence detection algorithms. In this paper, we employ mid-level audio features which are based on a Bag-of-Audio Words (BoAW) method using Mel-Frequency ...

Violence detection in Hollywood movies by the fusion of visual and mid-level audio cues

Acar, Esra ; Hopfgartner, Frank ; Albayrak, Sahin (2013)

Detecting violent scenes in movies is an important video content understanding functionality e.g., for providing automated youth pro- tection services. One key issue in designing algorithms for violence detection is the choice of discriminative features. In this paper, we employ mid-level audio features and compare their discriminative power against low-level audio and visual features. We fuse ...

Activating the Crowd: Exploiting User-Item Reciprocity for Recommendation

Larson, Martha ; Said, Alan ; Shi, Yue ; Cremonesi, Paolo ; Tikk, Domonkos ; Karatzoglou, Alexandros ; Baltrunas, Linas ; Geurts, Jozef ; Anguera, Xavi ; Hopfgartner, Frank (2013-10-12)

Recommender systems have always faced the problem of sparse data. In the current era, however, with its demand for highly personalized, real-time, context-aware recommendation, the sparse data problem only threatens to grow worse. Crowd-sourcing, specifically, outsourcing micro-requests for information to the crowd, opens new possibilities to fight the sparse data challenge. In this paper, we l...

Workshop and Challenge on News Recommender Systems

Tavakolifard, Mozhgan ; Atle Gulla, Jon ; Almeroth, Kevin C. ; Hopfgartner, Frank ; Kille, Benjamin ; Plumbaum, Till ; Lommatzsch, Andreas ; Brodt, Torben ; Bucko, Arthur ; Heintz, Tobias (2013-10-12)

Recommending news articles entails additional requirements to recommender systems. Such requirements include special con- sumption patterns, fluctuating item collections, and highly sparse user profiles. This workshop (NRS’13@RecSys) brought together researchers and practitioners around the topics of designing and evaluating novel news recommender systems. Additionally, we offered a challenge a...

The plista dataset

Kille, Benjamin ; Hopfgartner, Frank ; Brodt, Torben ; Heintz, Tobias (2013)

Releasing datasets has fostered research in fields such as information retrieval and recommender systems. Datasets are typically tailored for specific scenarios. In this work, we present the plista dataset. The dataset contains a collection of news articles published on 13 news portals. Additionally, the dataset comprises user interactions with those articles. We inctroduce the dataset’s main c...

Perceived and Actual Role of Gamification Principles

Meder, Michael ; Plumbaum, Till ; Hopfgartner, Frank (2013-12-09)

Although gamification has successfully been applied in office scenarios, it remains unclear how employees really feel about the introduction of a gamified system at their workplace. In this paper, we address this issue from two directions. First, we present the outcome of an online survey where we analyze users’ opinion about gamification in a workplace environment. Then, we analyze the interac...

Eine Methodik zur Entwicklung von Multiagenten-Systemen auf Basis von Geschäftsprozess-Modellen

Küster, Tobias (2017)

Seit vielen Jahren werden Multiagenten-Systeme als Abstraktion für komplexe und verteilte Softwaresysteme eingesetzt, und durch ihren Einsatz können zahlreiche Abläufe auf verständliche und intuitive Art und Weise dargestellt werden. Grundlegende Probleme verteilter Softwaresysteme bleiben jedoch oft bestehen: Der Entwickler sieht immer nur einen Teil des Programmcodes, nur eine Seite der Inter...

A framework for automated identification of attack scenarios on it infrastructures

Camtepe, Seyit Ahmet ; Bsufka, Karsten ; Hennig, Leonhard ; Simsek, Cihan ; Albayrak, Sahin (2012)

Due to increased complexity, scale, and functionality of information and telecommunication (IT) infrastructures, everyday new exploits and vulnerabilities are discovered. These vulnerabilities are most of the time used by malicious people to penetrate these IT infrastructures for mainly disruptingbusiness or stealing intellectual properties. Current incidents prove that it is not sufficient any...

Distributed log analysis for scenario-based detection of multi-step attacks and generation of near-optimal defense recommendations

Kaynar, Kerem (2017)

Detecting related, ongoing actions of attackers is significant for providing a complete situational assessment of security and determining the most effective reactive defense measures for a network. The logs generated by software running across the network can be used for this purpose, since they may contain the traces of malicious activities occurring inside the network. Primary logs that indi...

Security trade-offs in Cloud storage systems

Müller, Steffen (2017)

Securing software systems, is of paramount importance today. This is especially true for cloud systems, as they can be attacked nearly anytime from everywhere over the Internet. Ensuring security in general, however, typically has a negative impact on performance, usability, and increases the system's complexity. For cloud systems, which are built for high performance and availability as well a...

Affective analysis of videos

Acar Celik, Esra (2017)

As the amount of available multimedia content becomes more and more abundant, the use of automatic multimedia analysis solutions in order to find relevant semantic search results or to identify illegal content present on the World Wide Web has reached a critical importance. In addition, the advances in digital media management techniques have facilitated delivering digital videos to consumers. ...

Coordination algorithms for supply and demand matching in future power networks

Badawy, Rashad (2016)

It is envisioned that Smart power Grid will depend on a large number of renewable energy resources connected directly to the low and medium voltage power network(s). The dependence on the intermittent renewable energy resources for feeding consumption in real time leads to stability and reliability problems. Controllable loads or an active consumer network are one way to tackle these problems. ...

User modeling in the social semantic web

Plumbaum, Till (2015)

With the rise of the Web in the 1990’s, people got access to a yet unknown amount of information, finding themselves in the role of consumers of information. Since then, information on the Web has grown exponentially. All kinds of information - good, bad, incorrect, outdated or spam - can be found on the Web. With the availability of web-enabled mobile phones, people got ubiquitous access to th...

Automation in model-based usability evaluation of adaptive user interfaces by simulating user interaction

Quade, Michael (2015)

The goal of adaptive user interfaces (UI) is offering the opportunity to adapt to changes in the context of use and thus provide potentially improved interaction capabilities for different users in specific situations. But, this poses the challenge of evaluating usability aspects of many different variants of the resulting UI. Consequently, usability evaluations with real users or experts tend ...

Time series distance measures

Spiegel, Stephan (2015-08-14)

Zeitreihen kommen unter anderem in vielzähligen Bereichen der Medizin, Astronomie, Geophysik, Konstruktion, und Finanzwirtschaft vor. Im Allgemeinen bezeichnet man eine Zeitreihe als Sequenz von Datenpunkten die mit fortlaufender Zeit in gleichmäßigen Zeitabständen gemessen wurde. Diese These beschäftigt sich hauptsächlich mit der Auswertung von Zeitreihen, was die Segmentierung, Klassifikation...

Comparative assessment of cloud compute services using run time meta-data

Menzel, Michael (2015-08-18)

Die Menge verfügbarer Meta-Daten über Compute Service-Angebote erweist sich hinsichtlich Zuverlässigkeit, Aktualität und Vergleichbarkeit ungenügend. Zum Beispiel beschränken sich die von Compute Service-Anbietern veröffentlichten Meta-Daten über Leistungsattribute ihrer Angebote typischerweise auf Hardwarekennzahlen und sind daher nicht verwendbar für Vergleiche oder auch Planungsaufgaben wie ...

Cause and effect

Lützenberger, Marco (2015-03-26)

Aktuelle Verkehrssimulationssysteme sind in der Lage Verkehrssituationen nahezu realitätsgetreu abzubilden. Die meisten dieser Systeme bilden die Physik der zu simulierenden Elemente ab und reproduzieren auf Grundlage dieser Modelle das Verkehrsgeschehen von Straßen, Städten, ja sogar von ganzen Ländern. Gerne wird in diesen Modellen jedoch der Faktor Mensch vernachlässigt - dabei trägt Letzter...

Detecting adaptation conflicts at run time using models@run.time

Trollmann, Frank (2015-02-11)

Selbstadaptive Softwaresysteme sind in der Lage, sich an die Heterogenität heutiger Computersysteme anzupassen. Adaptionen ermöglichen eine korrekte Funktionsweise trotz unterschiedlicher Computerplattformen, Fähigkeiten, Konfigurationen und Kontextsituationen. Hierfür muss das Softwaresystem trotz der Änderungen durch Adaptionen immer korrekt funktionieren. Um dieses Ziel zu erreichen kann Ver...