Stefan Propp

Task Model-Based Usability Evaluation for Smart Environments

Task models are widely used within the research field of HCI for the model-based development of interactive systems. Recently introduced approaches applied task models further to model the cooperative behavior of people using devices within a smart environment. We describe a method of model-based usability evaluation to evaluate interactive systems, with a particular focus on smart environments, which are developed based on task models. We consider the evaluation in early development stages to interactively walk through the models and in later stages to execute a test case within a real environment. The paper provides results of a prototypical implementation.

Integration of usability evaluation and model-based software development

Model-based software development is carried out as a well defined process. Depending on the applied approach, different phases can be distinguished, e.g. requirements specification, design, prototyping, implementation and usability evaluation. During this iterative process manifold artifacts are developed and modified, including, e.g. models, source code and usability evaluation data. CASE tools support the development stages well, but lack a seamless integration of usability evaluation methods. We aim at bridging the gap between development and usability evaluation, through enabling the cooperative use of artifacts with the particular tools. As a result of integration usability experts save time to prepare an evaluation and evaluation results can be easier incorporated back into the development process. We show exemplary our work on enhancing the Eclipse framework to support usability evaluation for task model-based software development.

ViSE: a virtual smart environment for usability evaluation

Within the research field of HCI task models are widely used for model-based development of interactive systems. Recently introduced approaches applied task models further to model cooperative behaviour of people interacting in smart environments. However there is a lack of usability methods to support the needs of evaluations during a model-based development process for smart environments. Particularly during early stages of development building a prototypical environment for user evaluations is resource consuming. To overcome the challenges we present a process model and according tool support. We provide the virtual smart environment ViSE to conduct expert evaluations and user studies during a user-centred design process, supporting iterative evaluations.

HCI-Task Models and Smart Environments

The paper discusses the idea of using HCI-task models to support smart environments. It introduces a collaborative task modeling language CTML that allows the specification of collaboration and comprehensive dependencies in an OCL-like style. Additionally some ideas are presented that allow informing users and usability experts about the state of actors within smart environments. The paper provides the first results of a prototypical implementation.

Rapid Prototyping and Evaluation of Intention Analysis for Smart Environments

The development of smart environments is cumbersome and time-consuming compared to traditional software, since lacking a standard development process and according tool support. Smart environments are termed “smart” due to pro-active user assistance: User behavior is anticipated by an “intention analysis” software employing machine learning algorithms. In this paper we present a tool that facilitates the development of intention analysis by guiding the domain expert through the development process. Initially, the tool allows the user-centered design of HCI task models, without taking care of implementation details. Subsequently annotated task models are transformed into low level models, which are applied within the machine learning inference engine. We support both evaluation at early and later development stages. At early stages we evaluate designed models with expert-generated scenarios to simulate artificial low level sensor data. At later stages we evaluate a physical environment on the basis of real sensor data. A comparison between observed behavior and defined expectation allows identifying usability issues. A close connection between development and evaluation should further ensure rapid software changes and reevaluation to access improvements.

Integrating Usability Methods into Model-Based Software Development

Model-based software development is carried out as a well-defined process. Depending on the applied approach, different phases can be distinguished, for example, requirements specification, design, prototyping, implementation, and usability evaluation. During this iterative process, manifold artifacts are developed and modified, including models, source code, and usability evaluation data. CASE tools support the development stages well, but lack a seamless integration of usability evaluation methods. We aim at bridging the gap between development and usability, through enabling the cooperative use of artifacts with the particular tools. As a result of integration usability, experts save time to prepare an evaluation and evaluation results can be easily incorporated back into the development process. We show exemplary our work on enhancing the Eclipse framework to support usability evaluation for task model-based software development.

Towards Usability Evaluation for Smart Appliance Ensembles

Smart environments comprise users and devices to form ad-hoc an ensemble and assist the users to fulfill their tasks more efficiently and more conveniently. This introduces new challenges for usability evaluations. To cope with theses issues, we propose the application of task models. Following this approach the behavior of the users can be interpreted as a trace through the corresponding task model. We discuss our method of capturing, visualizing and analyzing traces through task models within smart environments. The paper provides the first results of a prototypical implementation.