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Re: MathML Usage for Styling

for

From: James A.
Date: Aug 1, 2016 4:07AM

The lack of standards and advice on best practice with how symbols are being styled/marked up is definitely an issue at the moment. While stand-alone equations maybe marked up using mathml (or similar) I have come across numerous examples where they are unintelligible to screen-reader/TTS users.

Below is a description of the experience of using NVDA with a paragraph from a scientific paper that I used to demonstrate the issue. This contains 3 equations within the text each marked up differently:

Equ 1: html - NVDA attempts to read this phonetically and it is not possible to perceive the contents correctly
Equ 2: mathml - NVDA first reads it phonetically then reads correctly using the mathml
Equ 3: image of equation with n alt-tag "View the MathML source" followed by a hidden container containing the MathML of the equation. NVDA reads the alt-tag followed by the equation read correctly using the mathml

In addition that paragraph contains <em>C<sub>j</sub> &nbsp;</em> which should be read as C subscript j but is reads as C j and <em>topN</em>&nbsp;⩽&nbsp;<em>N</em> which is read as top N N missing out the "less than or equal to" (screen readers seem to only read the few most common html entities).

The standalone equations are read correctly using a hidden class containing the mathml. I get a similar results when using Read&Write Gold except Equ 2 is not read aloud but this is read correctly if mathjax is turned on (although that stops NVDA reading the equations...).

This is just 1 paragraph on 1 paper...

I have conversations with STEM publishers who are keen to improve accessibility. They are in a catch-22 situation as the content they are publishing meets the current standards but they would like more guidance as you can see they are using many different approaches. The main culprit seems to be the use of html entities and mark-up when the content should be semantically tagged as maths.

Regards

Abi


=====================================Dr Abi James
Research Fellow
Accessibility Team, WAIS, ECS
University of Southampton
Web: https://access.ecs.soton.ac.uk/
Email: <EMAIL REMOVED>