Gaby Nordbrock

Bio: Gaby Nordbrock is an academic researcher from Fraunhofer Society. The author has contributed to research in topics: Usability & Usability engineering. The author has an hindex of 4, co-authored 7 publications receiving 23 citations.

The usability of accessibility evaluation tools

Abstract: A range of accessibility evaluation tools are available to support Web developers in producing accessible Web resources. It is important that these tools support web developers very well, so that the developers can concentrate on the tasks of Web development. In addition, the tools should enhance Web developers understanding of accessibility issues. This paper presents a usability evaluation of five entry level accessibility evaluations tools. A group heuristic evaluation was conducted, with 5 experts in usability and accessibility working through each tool together, but rating usability problems separately. The results showed that the usability of these tools is surprisingly poor and that they do not support web developers adequately in checking the accessibility of their web resources.

Group-Based Expert Walkthroughs to Compensate for Limited Access to Target User Groups as in Case of Chronically Ill Patients

Abstract: Involvement of real end users right from the beginning of an IT project is understood nowadays as good practice particularly in research projects where new and innovative concepts are to be investigated. In some situations, this is not feasible though, because this would cause unreasonable burden on target users, e.g., in case of chronically ill older patients or it is simply not possible, because administrative hurdles like permission by ethical committees need to be overcome, therefore it is necessary to install substituting methods. In the PICASO project (Personalised Integrated Care Approach for Service Organisations and Care Models for Patients with Multi-Morbidity and Chronic Conditions) this was achieved by implementing group-based expert walkthroughs where experts with different work-domain expert knowledge, in this case from usability, accessibility, clinical practice and software development, walked through an application by following typical usage scenarios target users are supposed to achieve. In contrast to the original method outcomes of walkthroughs were documented in form of software requirements, i.e. essential functionalities and features of the envisioned application instead of usability and accessibility issues. This way a reference document for developers evolved that closed the gap in bringing user requirements to application development.

IPCA: Adaptive Interfaces Based upon Biofeedback Sensors

Abstract: This paper presents some preliminary results of the IPCA project, targeted to the development adaptive interfaces for people with severe motor and speech impairments based upon biofeedback sensors. We will introduce the results of the user requirements capture and their influence in the project prototype being developed at the moment.

Controlled natural language sentence building as a model for designing user interfaces for rule editing in assisted living systems --- a user study

Abstract: As part of the web-based services developed within the WebDA-project the Action Planner was implemented to allow care givers of people with dementia to support them in accomplishing activities of daily living and counteract restlessness amongst others. In order to define rules that include a description of situations indicating e.g. restlessness as well as an action that should be undertaken in such situations, a user interface was designed enabling care givers to express these rules in a controlled natural language setting. Here, rule expressions were offered in preformulated natural sentences that could be manipulated by changing (pre)selected notions as "daily" in pop-up menus embedded in the sentences. A user study was conducted with 24 test participants (12 65 years) proofing that this approach can be understood as intuitive and well usable also for test participants beyond 65 years of age.

Accessibility challenges and tool features: an IBM Web developer perspective

Abstract: Using evidence from a survey of 49 IBM Web developers we explore two concerns: barriers to the developers' designing accessible Web-based products, and what value they felt specific features in an "accessibility" tool might have. They found designing for accessibility difficult, but more surprisingly, they found using the test tools and finding technology work-arounds equally hard. Testing and finding work-arounds were also the most time consuming aspects of accessibility, while design was not. When asked about tool features, all agreed that a checklist of automatically detected problems and an explanation of each problem were the most important. There were fifteen features in all, and the more experienced the developer, the more they valued the other features, particularly being able to experience a site as someone with a particular disability would, and being able to pinpoint a problem on the rendered view of a page. The survey results suggest existing tools are often unclear, cumbersome, and incomplete with respect to the standards that must be met.

Affective brain-computer interfaces: Psychophysiological markers of emotion in healthy persons and in persons with amyotrophic lateral sclerosis

Abstract: Affective Brain-Computer Interfaces (BCI) are systems that measure signals from the peripheral and central nervous system, extract features related to affective states of the user, and use these features to adapt human-computer interaction (HCI). Affective BCIs provide new perspectives on the applicability of BCIs. Affective BCIs may serve as assessment tools and adaptive systems for HCI for the general population and may prove to be especially interesting for people with severe motor impairment. In this context, affective BCIs will enable simultaneous expression of affect and content, thus providing more quality of life for the patient and the caregiver. In the present paper, we will present psychophysiological markers for affective BCIs, and discuss their usability in the day to day life of patients with amyotrophic lateral sclerosis (ALS).

Approche multimodale pour l'évaluation d'applications de communication innovantes

Abstract: Le domaine des applications de communication a connu dernierement de grands bouleversements, ce qui a conduit les chercheurs a suivre un nouveau paradigme d’evaluation, base sur l’experience utilisateur. Un grand nombre de methodes de mesure ont ainsi ete mises au point afin de la mesurer, mais demeurent immatures, voire contradictoires entre elles. C’est pourquoi un travail merite d’etre mene afin d’en augmenter la validite et la fiabilite. Ce travail de these s’est attache donc a utiliser plusieurs de ces methodes, de les combiner et les articuler selon differentes techniques afin d’ameliorer la qualite de la mesure. Nous nous sommes appuyes pour cela sur un large spectre d’indicateurs, d’ordre physiologiques, comportementaux et auto rapportes et de deux strategies de triangulation en particulier : multi-facettes et multi-mesures. Enfin, ces methodes ont testees dans des cas d’application reels et selon une complexification croissante des procedures et traitements statistiques. Cela a donne lieu a trois etudes distinctes. La premiere a consiste a evaluer la pertinence d’un algorithme de recommandation de films face a son concurrent en utilisant une strategie d’evaluation multi-facettes. Une deuxieme etude a ete elaboree afin de tester la pertinence de modeles d’evaluation multi-mesures, en evaluant l’utilisabilite de sites universitaires grâce a un logiciel de test utilisateur a distance (Evalyzer) et la combinaison multimodale de divers indicateurs d’utilisabilite. Enfin, une derniere etude a ete realisee afin de valider un protocole de mesure d’immersion multi-mesure (questionnaire, expression faciale, conductance de la peau, rythme cardiaque, comportement oculaire). Ces trois etudes nous ont permis d’evaluer la pertinence d’un certain nombre de mesures (d'utilisabilite et d’experience utilisateur), la valeur ajoutee de certaines de leurs combinaisons, ainsi qu’un retour critique sur la procedure de validation multi-facettes utilisee dans cette these

Accessibility of Portuguese Public Universities' sites.

Abstract: The aim of this study is to characterise the accessibility of all Public Portuguese Universities' homepages and the support services they offer to disabled students. We employed two different online automatic tools: using the 'eXaminator' to determine the conformance of websites to checkpoints; using 'HERA' to identify any automatically detectable errors or checkpoints. The choice of these tools was according to the Portuguese Government recommendation, to public in general, as the ones best suited to perform accessibility check-ups. Thus, we used those tools to present a brief characterisation of the sites' accessibility. The data collection took place in 2007, 2008 and 2009 to identify differences. Following this work, we chose all the sites that stated to have specific services to support disabled students and made a detailed analysis to: (a) identify existing university services to disabled students; (b) identify possible relations among the accessibility' scores in the universities that offer services to disabled students. The main results of this study were as follows: schools overall accessibility of the webpage were not acceptable and only 12.5% sites had information regarding supporting services to disabled students. The data collected identified an overall web accessibility improvement during the 2007-2008, followed by a stabilisation of the results.

Aphasic Communities of Learning on the Web

Abstract: This article presents the case study of a cooperative Web-learning environment — SOCRATES — to foster barrier-free learning on the Web. While the growth of the Internet was exponential in the last years, still many communities don’t benefit from Web-learning technology due to improper tools and constricted communication processes. These problems increase when developing applications for communities of people with special needs. SOCRATES supports a community of learning comprising patients suffering from aphasia (aphasics), therapists, researchers on linguistics, and system developers. Aphasics can improve their conversation skills with a specially designed talk/chat tool, while therapists and linguistic researchers can monitor conversations from automatically generated transcripts. Aphasics in remote areas using SOCRATES are now able to communicate freely among each other without being afraid that they might get lost in rapid conversation in a distributed privacy protecting virtual community.