Friday, 18 April 2008

Education: Accessibility

Today on Slashdot there is a post about website accessibility for the blind. There are some views and some comments which I find unbelievable. Provision for visual impairment is still very poor. There are still not effective ways of presenting web-content which is by its nature visual. Flash is a particular bug-bear although I have been to meetings where they have talked about making Flash accessible. One of the main problems is that if you are visually impaired one way you interact with visual media is by touch and you cannot do this with a computer screen.

The question of making our online statistics course accessible caused some heated debate. I wanted to render the equations as images - the course was written in LaTeX and you can do this usng mimeTex. The web learning people wanted it all as MathML for accessibility and to comply with the Disability Discrimination Legislation in the UK. For me the development time of the conversion to MathML is too long as there is no simple translation/parsing tool. This meant that the course was almost not available to any students visually impaired or not. In the end we did it in MathML but the clarity of the equations for everyone suffers.

By writing it in LaTeX I have a source that can readily be converted to Braille and provide a hardcopy of the course material. For me this is the only way to deal with complex equations, reading them out loud from a browser is not useful as the equation is a whole and reading it linearly it loses its sense. The important part of online learning is the interaction between students, how they get the raw materials is less important. So if the website does not provide the right type of resource then why shouldn't it be supported with paper materials?

I still have never had a visually impaired student on any of my courses although I have interviewed some and we have explored with them how we could help them within the course. It is a difficult problem for online learning but one where you have to think about what part of the content is important and ask what aspects of the course are people with different dissabilities missing out on?


Anonymous said...

It is true that accessibility in mathematics via MathML has not yet advanced to the point where it does a 100% job. However, it has come a long way and is still progressing. While math accessibility via speech generated from MathML is not perfect, it is still a better solution than converting LaTeX to speech or braille UNLESS the person in question already knows LaTeX. After all, it is as linear as MathML generated speech. Since most of the people that do math in the world do not know TeX or LaTeX, they would have even more to learn. Math speech generated from MathML, on the other hand, would be closer to how math is spoken. Even mathematicians who live and breath TeX don't use it to speak mathematics to each other. Can you imagine two mathematicians discussing an equation at the whiteboard with "backslash" this and "backslash" that?

Andy said...

It depends on how LaTeX braille converts equations - and how you can put equations into braille. If it does them holistically rather than giving the TeX code then that is better.

For me the problems with MathML are browser issues. Why can't the browsers come with fonts for rendering maths and why can't Microsoft embed it into Internet Explorer?

Andy said...

If you want to see an article about equations in Braille see

The Braille can be generated from a subset of LaTeX commands.