Grouping hyperlinks for improved voice/mobile accessibility

Alex Penev

UNSW / NICTA (Australia)

Accessibility

Heavily presentation-oriented web blind users “read” sequentially

layout gets in the way

Accessibility

Heavily presentation-oriented web blind users “read” sequentially

layout gets in the way

mobile users have small-screen devices For some users, “less is more”

Hyperlinks

Often visit a site with intention of following a link

Hyperlinks

Often visit a site with intention of following a link

Idea: cluster links partition a page’s links into topical

groups helps find a link (cf. IVR) way to organize a set of links

Example: Centrelink.gov.au

Government agency, human services Population obtains info, forms, etc. …but do not visit regularly

information need

Centrelink

111 links on the page Some problems for blind users:

pop-up menus flatten it?

Centrelink

111 links on the page Some problems for blind users:

pop-up menus flatten it?

Some problems for mobiles: hard to fit/navigate a 3-tier pop-up menu

Link clustering

Group related links together hopefully in topical groups

Link clustering

Group related links together hopefully in topical groups

How? label links with descriptions partition descriptions assign summary label to each cluster

Link clustering

Navigation process: invoke clustering step presented with clusters

advertise a label

Link clustering

Navigation process: invoke clustering step presented with clusters

advertise a label

select best-sounding cluster layout is lost

Faster than serial reading

Forming descriptions

A set of keywords for each link anchor text, nested tags, URL, content

Forming descriptions

A set of keywords for each link anchor text, nested tags, URL, content

further possibilities: anchor text window, folksonomy tags, <meta>, ontology

Example australia.gov.au

australia, gov, government, website, travel, taxes, business, people, immigration, etc.

Forming descriptions

Descriptions can be short and have little overlap

Solution?

Forming descriptions

Descriptions can be short and have little overlap

Solution? take into account layout by spreading a

link’s influence across DOM borrow descriptions from neighbor links decay weight with distance

Clustering step

Propagation enriches descriptions relates neighboring links less sparse feature vectors

good for clustering!

Use a partitioning algorithm e.g. k-means

Possible uses

Blind users navigate to link via clustering

skip layout, skip uninteresting topics general surfing?

Possible uses

Blind users navigate to link via clustering

skip layout, skip uninteresting topics general surfing?

Mobile users portal pages

Sample results - Centrelink

12 clusters agency, site, main sections, welfare

allowances, study & training, health, carers, family, children, maternity & job search/retirement, farming, online security

Full table in paper

Conclusion

Simple, well-known ideas applied to a different problem VSM (tf.idf), clustering

May help voice/mobile browsing Future work

what is a good description? what is a good label?