Internet System for the Disabled Evaluated
It is not enough to have a Braille keyboard or a computer that speaks. Until Internet can better adapt to their needs, disabled persons will continue to have a big disadvantage with respect to other users. With his PhD thesis, researcher Mr Markel Vigo aimed to smooth out this complicated relationship. On the one hand, he tested a system that facilitates creating a more personalised Internet for the disabled and, on the other, devised innovative techniques for experts in adapting web pages.
Automatic assessment of contextual web accessibility from an evaluation, measurement and adaptation perspective is the title of Mr Vigo’s PhD. Almost all the thesis deals, directly or indirectly, with a system known as Web Accessibility Quantitative Metric (WAQM), which automatically measures the level accessibility of each web page. WAQM is moreover a flexible system; the level of accessibility can be measured according to the type of disability of each person. And while each type of disability cannot be exactly measured in a complete manner, (for example, amongst blind persons there are many kinds), Mr Vigo has shown that the system is reliable, having been evaluated by two panels of, respectively, experts in the matter and blind persons.
The evaluation tools automatically create a report for each web page. Then the WAQM system makes an algorithm with this data about the web page in order to calculate its level of accessibility. In this way, when a blind person carries out a search on the Internet, criteria related to their disability are taken into consideration, along with the usual search criteria. Beside each link there appears the scoring corresponding to the level of accessibility. According to Mr Vigo, thanks to this system, persons with disability are more confident and have more control when carrying out a search on the Internet.
The WAQM system enables the addition of all kinds of variations. This is why Mr Vigo has identified the essential criteria for measuring accessibility in the case of a person with disability, i.e. the help technology (for example, tools that enlarge the letters on the screen or provide the PC with a voice), access to the Internet and the type of discapacity. According to Mr Vigo, it is especially important to specify the device for accessing the Internet and the type of discapacity of the user. Knowing if the user accesses the Internet through a normal PC, a laptop or a PDA is especially effective for the system to give a correct result; as well as specifying what disability group the person belongs to (blind persons, in the case of this thesis).
The user’s profile is drawn up on the basis of all this and then this profile is used to personalise the report that the evaluation tools automatically create for the web page. This is how the search, based on the needs of the disabled person, is carried out.
Also for experts
Apart from use by end-users, the WAQM system is highly useful for experts who adapt web pages, above all because it helps to effectively measure the web page once adapted.
In fact, Mr Vigo also took into account these experts on writing his thesis and has described a language called Unified Guidelines Language (UGL) for them. It is precisely by means of the UGL that reports for each web page are automatically created, essential for subsequent measurement of accessibility with the WAQM system.
In the words of the researcher, the UGL will greatly help to enhance accessibility to web pages, thanks to the fact that it facilitates the editing, updating and insertion of new criteria, amongst other advantages. UGL is a very flexible language that enables changing certain previous criteria and adding others, without the need to start from the beginning. Moreover, it provides adaptation resources to those experts that are not familiar with the language in question.
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