2009, Gerken, Jens, Reiterer, Harald

Während klassische Experimente oder Usability Tests oft nur eine Momentaufnahme darstellen, ermöglichen es Längsschnittstudien auch Veränderungen zu beobachten und zu einem ökologisch valideren Gesamtbild der Gebrauchstauglichkeit zu gelangen. Bislang werden derartige Verfahren aber noch sehr selten in der Mensch-Computer Interaktion eingesetzt. In diesem Beitrag wird auf Basis einer umfangreichen Literaturanalyse eine Taxonomie vorgestellt, die einen Überblick über die vielfältigen Möglichkeiten von Längsschnittstudien ermöglicht. Hierdurch kann sowohl der wissenschaftliche Diskurs verbessert werden, um die bekannten Ansätze weiter zu verbessern, als auch dem praktischen Anwender Hilfestellung in Planung und Durchführung einer Längsschnittstudie gegeben werden.

2009, Geyer, Florian, Memmel, Thomas, Reiterer, Harald

2009, Öttl, Sonja, Gundelsweiler, Fredrik, Reiterer, Harald, Brandes, Ulrik

2009, Jetter, Hans-Christian, König, Werner A., Reiterer, Harald

In this paper we provide a threefold contribution to the Surface Computing (SC) community. Firstly, we will discuss frameworks such as Reality-based Interaction which provide a deeper theoretical understanding of SC. Secondly, we will introduce our ZOIL user interface paradigm for SC on mobile, tabletop or wall-sized devices. Thirdly, we will describe our two software tools Squidy and ZOIL UI Framework which have supported and facilitated our iterative design of SC prototypes.

2009, König, Werner A., Rädle, Roman, Reiterer, Harald

We introduce the interaction library Squidy, which eases the design of natural user interfaces by unifying relevant frameworks and toolkits in a common library. Squidy provides a central design environment based on high-level visual data flow programming combined with zoomable user interface concepts. The user interface offers a Simple visual language and a collection of ready-to-use devices, filters and interaction techniques. The concept of semantic zooming enables nevertheless access to more advanced functionality on demand. Thus, users are able to adjust the complexity of the user interface to their current need and knowledge.

2009, Gerken, Jens, Bieg, Hans-Joachim, Reiterer, Harald

In this paper we present our experiences with longitudinal study designs for pointing device evaluation. In this domain, analyzing learning is currently the main reason for applying longitudinal designs. We will shortly discuss related research questions and outline two case studies in which we used different approaches to address this issue.

2009, König, Werner A., Rädle, Roman, Reiterer, Harald

In contrast to the pioneers of multimodal interaction e.g. Richard Bolt in the late seventies, today s researchers can benefit of a wide variety of existing interaction techniques, devices and frameworks. Although these tools are available, the usage of them is still a great challenge particularly in terms of usability. A major issue results from the trade-off between the functionality of the system and the simplicity of use. We introduce a novel visual user interface concept which is especially designed to ease the design and development of post-WIMP user interfaces including multimodal interaction. It provides an integrated design environment for our interaction library Squidy based on high-level visual data flow programming combined with zoomable user interface concepts. The user interface offers a simple visual language and a collection of ready-to-use devices, filters and interaction techniques. We specifically address the trade-off between functionality and simplicity by utilizing the concept of semantic zooming which enables dynamic access to more advanced functionality on demand. Thus, developers as well as interaction designers are able to adjust the complexity of the Squidy user interface to their current need and knowledge.

2009, Foehrenbach, Stephanie, König, Werner A., Gerken, Jens, Reiterer, Harald

Human beings perceive their surroundings based on sensory information from diverse channels, However, for human-computer interaction we mostly restnct the user on visual perception. In this paper, we contribute to the investigation of tactile feedback as an additional perception modality, Therefore, we will first discuss existing user studies and provide a classification scheme for tactile feedback techniques, We will then present and discuss a comparative evaluation study based on the ISO 9241-9 IErgonomic requirements for office work with visual display terminals (VDTs) - Part 9: requirements for non-keyboard input devices, 20001, The 20 participants performed horizontal and vertical one-directional tapping tasks with hand gesture input with and without tactile feedback in front of a large, high-resolution display. In contrast to previous research. we cannot confirm a benefit of tactile feedback on user performance. Our results show no significant effect in terms of throughput (effective index of performance (IPe)) and even a significant higher error rate for horizontal target alignment when using tactile feedback. Based on these results. we suggest that tactile feedback can interfere with other senses in a negative way. resulting in the obselved higher error rate for horizontal targets. Therefore, more systematic research is needed to clarify the innuencing factors on the usefulness of tactile feedback. Besides these results, we found a significant difference in favor of the horizontal target alignment compared with the vertical one in terms of the effective index of performance (lPe), confirming the work by Dennerlein et al.

2009, Reiterer, Harald, Heilig, Mathias, Rexhausen, Sebastian

Knowledge work is a demanding activity caused on the one hand by the increasing complexity of today s information spaces. On the other hand, knowledge workers are acting correspondingly to an individual creative workflow, which involves multifaceted characteristics like diverse activities, locations, environments and social contexts. Although it is important to find solutions to specific aspects of knowledge work (information-seeking, information-management, media-warehousing, etc.) our design approach MedioVis 2.0 tries to support the entire workflow in one coalescing Knowledge Media Workbench, showcased in the context of digital libraries. To achieve this goal, we apply the concept of zoomable user interfaces, different visualization techniques and investigate additional considerations to provide a satisfying user experience.

2009, König, Werner A., Gerken, Jens, Dierdorf, Stefan, Reiterer, Harald

We present Adaptive Pointing, a novel approach to addressing the common problem of accuracy when using absolute pointing devices for distant interaction. First, we discuss extensively some related work concerning the problem-domain of pointing accuracy when using absolute or relative pointing devices. As a result, we introduce a novel classification scheme to more clearly discriminate between different approaches. Second, the Adaptive Pointing technique is presented and described in detail. The intention behind this approach is to improve pointing performance for absolute input devices by implicitly adapting the Control-Display gain to the current user‟s needs without violating users‟ mental model of absolute-device operation. Third, we present an experiment comparing Adaptive Pointing with pure absolute pointing using a laser-pointer as an example of an absolute device. The results show that Adaptive Pointing results in a significant improvement compared with absolute pointing in terms of movement time (19%), error rate (63%), and user satisfaction.