Rui Lopes

On web accessibility evaluation environments

Modern Web sites leverage several techniques (e.g. DOM manipulation) that allow for the injection of new content into their Web pages (e.g., AJAX), as well as manipulation of the HTML DOM tree. This has the consequence that the Web pages that are presented to users (i.e., browser environment) are different from the original structure and content that is transmitted through HTTP communication (i.e., command line environment). This poses a series of challenges for Web accessibility evaluation, especially on automated evaluation software.n This paper details an experimental study designed to understand the differences posed by accessibility evaluation in the Web browser. For that, we implemented a Javascript-based evaluator, QualWeb, that can perform WCAG 2.0 based accessibility evaluations in both browser and command line environments. Our study shows that, in fact, there are deep differences between the HTML DOM tree in both environments, which has the consequence of having distinct evaluation results. Furthermore, we discovered that, for the WCAG 2.0 success criteria evaluation procedures we implemented, 67% of them yield false negative answers on their applicability within the command line environment, whereas more than 13% of them are false positives. We discuss the impact of these results in the light of the potential problems that these differences can pose to designers and developers that use accessibility evaluators that function on command line environments.

A Semantic Accessibility Assessment Environment for Design and Development for the Web

The Web is now increasingly being accessed by many people with disabilities. Thus, the great heterogeneity of Web application technologies as well as the provided Web content requires the introduction of accessibility aspects in order to fulfill the preferences for all people with disabilities or not. For that reason accessibility support at all stages of the design and development process of Web applications should be a solution that appears in the horizon. New developed Web applications should be fully adapted to different user needs, and totally accessible regardless of the specific condition of end users. Our approach introduces an advanced semantic accessibility assessment environment which initializes semantic models representing the most of main accessibility constrains and terms which are required for the design and development of Web applications, through the use of generic and domain ontologies. The proposed assessment environment can be used for the accessibility assessment of Web applications during the design and development phase.

Redefining assumptions: accessibility and its stakeholders

Accessibility is becoming more and more relevant in Information technologies, such as theWeb and software applications, particularly due to the push on legislation to make public services accessible to everyone. While most accessibility issues are envisioned by the developer-user dichotomy, several stakeholders are responsible for the successful implementation of accessible software and services for all users. n nIn this paper we present an exploratory study on the current state of accessibility as perceived by its main stakeholders: developers, service providers, public bodies, accessibility assessors, and elderly and people with disabilities. By surveying more than 400 individuals, we have confirmed some of the expectations and results from other surveys, such as the perception about the lack of understanding and application of Web accessibility guidelines. We have found that this issue gets even worse outside the scope of the Web, for all stakeholders. Another eye-opening finding is that all stakeholders are welcome to the simulation of assistive technologies, in order to widen the perception and involvement of accessibility in the software development process.

Towards the universal semantic assessment of accessibility

The ever increasing adoption of software technologies has bring closer technology to users with disabilities and users that interact with devices other than a PC. This diversification poses a real challenge to developers when creating software that has to cope with a myriad of interaction situations, as well as specific directives for ensuring an accessible interaction. In this paper we present SAAF, the Semantic Accessibility Assessment Framework. SAAF provides a set of constructs to describe the semantics of accessibility assessment procedures that can cope with different users, devices, and software technologies in a coherent and formalised way. SAAF affords the description of users and devices, their constraints and requirements, in the light of different accessibility assessment procedures. We exemplify the usage of SAAF by applying it in the context of the Web and related accessibility best practices such as WCAG.

Results from multi-dimensional accessibility assessment

This paper discusses the variability of websites accessibility using a multi-dimensional evaluation that considers specific sets of relevant guidelines according to different devices and different disability types. We use an accessibility evaluation framework that is able to explore different combinations of guidelines from web content accessibility and mobile web best practices. It was applied to evaluate a set of interesting case studies. The obtained results show that the web content presents different accessibility issues regarding specific disability types, always a subset of the universal accessibility assessments. Regarding the devices dimension, results of the assessment show significant differences depending on the web resource representation for different devices. In all cases the dissimilarities between the general accessibility assessment and the evaluation for specific disabilities were visible.

An architecture for multiple web accessibility evaluation environments

Modern Web sites leverage several techniques that allow for the injection of new content into their Web pages (e.g., AJAX), as well as manipulation of the HTML DOM tree. This has the consequence that the Web pages that are presented to users (i.e., browser environment) are different from the original structure and content that is transmitted through HTTP communication (i.e., command line environment). This poses a series of challenges for Web accessibility evaluation, especially on automated evaluation software.In this paper, we present an evaluation framework for performing Web accessibility evaluations in different environments, with the goal of understanding how similar or distinct these environments can be, in terms of their web accessibility quality.

The semantics of personalised web accessibility assessment

This paper presents SAAF, a Semantic Accessibility Assessment Framework for personalised Web accessibility assessment procedures. We define four domains as a way to decouple general accessibility concepts and semantics (e.g., disabilities, device descriptions) from technology or assessment specific concepts. We leverage personalised Web accessibility by transforming questions such as is this Web site accessible to me? into rich-semantics queries on SAAF and integrate it into a Web accessibility evaluator.