J. Eduardo Pérez

Assessment of Semantic Taxonomies for Blind Indoor Navigation Based on a Shopping Center Use Case

Despite the growing availability of location-based services (LBS) to support pedestrian activities, we know little about the effectiveness of existing geographical web information to assist the indoor navigation of people with special needs such as the visually impaired. To characterize these indoor environments, we surveyed three different specifications about taxonomies for environmental semantic information. Survey results show that even having different scopes, the three studied specifications share considerable environmental semantic information. In order to evaluate the validity of survey results, we created a set of environmental semantic information for a shopping center, and then performed a navigation experiment with 9 visually impaired participants in the same indoor location. A smartphone-based system providing audio navigation assistance based on accurate real-time localization in the shopping center was used to complete navigational tasks. Experiment results show an overall positive assessment from participants about the usefulness of the audio messages used. We present further findings about the assessment of the different audio messages by the study participants.

Assisted Interaction Data Analysis of Web-Based User Studies

User behaviour analysis requires defining experimental sessions with numerous participants. In this context, the specification of experiments is a demanding task, as several issues have to be considered such as the type of experiment, the type and number of tasks, the definition of questionnaires and the user interaction data to be gathered. The analysis of collected data is also complex and often requires repeatedly examining recorded interaction videos. In order to deal with these tasks, we present a platform called RemoTest which assists researchers to specify and conduct experimental sessions as well as to gather and analyse the interaction data. This platform has been applied to define different formal user studies on the web and has assisted researchers in detecting the main interaction characteristics of different user profiles and settings.

User individuality management in websites based on WAI-ARIA annotations and ontologies

In this paper, we describe a system for adapting websites based on an annotation approach. The system adapts annotated websites according to the user characteristics. The core of the system is composed of a repository containing a comprehensive set of adaptation techniques. 99 techniques have been identified and classified, 48 of them have been fully implemented in the system. This wide range of implemented techniques provides the system with the necessary mechanisms for adapting diverse aspects of website interfaces, such as the content to display, the layout and the structure. The techniques to apply for a given user are inferred according to the information stored in an ontology. This defines the bases for associating user characteristics with the adaptation techniques to apply for specific interaction elements annotated in a website. An annotation language based on the roles and properties of WAI-ARIA has been elaborated. Therefore, any website annotated in this language can be adapted. This adaptation system has been applied to two different websites and adapted interfaces have been obtained for three different user groups.

Depicting the Keypad Mouse Interface: Exploring Pointing Behaviors of Three Input Devices

Using standard keyboard for pointing and clicking interactions seems to be an affordable option for people who have difficulties handling a standard mouse due to a lack of dexterity or temporal disability conditions. The keypad mouse uses discrete input based on keystrokes to perform cursor movements. This distinctive feature along with others related to cursor motion behavior, make the keypad mouse a unique pointing interface when compared with alternatives. We have carried out a study with expert users of different pointing devices. Results of the study revealed significant differences in the performance values among participants in the three groups. Direction on aimed cursor movements proved to be a crucial factor to be taken into account for keyboard-only users. The findings presented in this paper have a broad application when it comes to designing effective predictive models as well as to proposing design guidelines, novel interaction techniques and adaptation techniques for this collective.

Exploring the Web navigation strategies of people with low vision

People with low vision experience accessibility barriers when they interact with the web. This paper explores the navigation strategies of low vision users in order to select the appropriate accessibility techniques to design web interfaces for them. For this purpose, an exploratory study was carried out with six users with low vision. The results revealed the heterogeneity in the group of people with low vision and the variety of navigation strategies applied. Observations and analysis of data gathered in experimental sessions allowed a set of techniques to be defined that can improve accessibility for people with low vision when interacting with the web.

Inclusive Web Empirical Studies in Remote and In-Situ Settings: A User Evaluation of the RemoTest Platform

ABSTRACT Web accessibility evaluation requires tests to be carried out with real users with disabilities performing real tasks or activities. To recruit an appropriate group of users and to observe their performance in the real world is difficult. For this reason we have developed RemoTest, a platform that assists researchers designing experiments, conducting remote and in-situ experimental sessions and analyzing the data gathered while the users are accessing the Web. Although this tool is oriented to experimenters, it is necessary to check whether the evaluation environments created by RemoTest are accessible or not to the users that participate in the tests. To this end, we conducted formal in-situ evaluations with 36 users with diverse characteristics. For this assessment, the participants were asked to install the platform, to fill in some automatically created questionnaires and to carry out several web navigation tasks. From the data gathered we analyzed the ease of the installation process, the accessibility of the automatically generated questionnaires, and user satisfaction. The results revealed the suitability of the platform for conducting inclusive experiments both in remote and in-situ contexts and provided guidelines on how the experiments should be set out.

Virtual cursors to enhance web accessibility for people with limited dexterity: usability test results and future directions

Basic web interactions, such as pointing and clicking links with an on-screen cursor, can be highly challenging for people with a lack of dexterity in their hands or arms. Much research has been done on studying point and click interactions, but most of this has focused mainly on able-bodied people interacting with standard pointing devices. In this paper, we present the design and the usability evaluation of two virtual cursors for assisting motor-impaired users when pointing and clicking links while browsing the Web. Results of a usability study involving nine motor-impaired and six able-bodied users applying their usual pointing device in a web-based experiment are presented. According to their self-reported assessments, the results show the acceptance and usefulness of both virtual cursors compared to the original unassisted one, underlining the importance of providing motor-impaired people with virtual enhancements to improve their web browsing ability.

Mintzatek, Text-to-Speech Conversion Tool Adapted to Users with Motor Impairments

Text-to-speech (TTS) conversion software tools are capable of generating synthetic voice from written text. These tools are essential for some groups of impaired users who have speech difficulties. In some cases, this limitation is caused by some kind of motor impairment. However, current TTS tools are not fully accessible as contain barriers for those users with limited mobility in upper extremities. This paper presents the most significant accessibility barriers detected for this specific user group. In addition, an accessible TTS tool, Mintzatek, has been implemented based on User-Centered Design (UCD) process. The user interface of the developed tool is adapted to users with limited mobility in upper extremities. All the development process has been guided by two real motor impaired users with plenty of experience in the use of assistive technologies.