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Accessibility

Accessibility. Web should be usable by everyone This includes users with: Vision impairments Hearing impairments Mobility impairments. Statistics. 8 million people with visual impairments 20 million deaf or hard-of hearing 250,000 with spinal cord injuries 500,000 with cerebral palsy

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Accessibility

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  1. Accessibility • Web should be usable by everyone This includes users with: • Vision impairments • Hearing impairments • Mobility impairments

  2. Statistics • 8 million people with visual impairments • 20 million deaf or hard-of hearing • 250,000 with spinal cord injuries • 500,000 with cerebral palsy • 330,000 with MS • More that half US population over 65 has some type of impairment

  3. Issues involving Vision • Web very visually oriented • Significant challenges • Severity ranges from total blindness to low vision • Color blindness • Visual Stimuli

  4. Information Delivery • Information display on traditional monitor not available to users with visual impairments Two assistive technologies: • Screen Readers • Refreshable Braille displays

  5. Screen readers Reads text component of web screen Includes: • Links • Menus • Dialog Boxes • Error Messages

  6. Screen Readers • Several vendors offer screen readers • Prices range from $300 to $1000 • Page must be reformatted to support screen readers • HTML “lang” attribute controls language page will be read in

  7. Refreshable Braille Display • For people who are deaf as well as blind screen readers do not work. • Translates text of page into Braille • Single line of Braille text • Prices range from $4500 to $14,500

  8. Grade II Braille

  9. Refreshable Braille Display

  10. Reformatting Text • For screen readers to work text of page must be formatted to support linear delivery • Tabular data • Label for Elements • Skip navigation • Alt Tags for images

  11. Tabular Data

  12. Markup Strategy for Tables • <table border="1"> • <thead> • <tr> • <th id="c1"> Course </th> • <th id="c2"> Time </th> • <th id="c3"> Day </th> • <th id="c4"> Prerequisiste </th> • <th id="c5"> Instructor </th> • <tr> • </thead> • <tbody> • <tr> • <td headers="c1">211</td> • <td headers="c2"> 11:30 pm -1:00 pm</td> • <td headers="c3">MW</td> • <td headers="c4">None</td> • <td headers="c5">McDonald</td> • </tr> • <tr> • <td headers="c1">211</td> • <td headers="c2"> 10:30am - 12:00 pm</td> • <td headers="c3">TR</td> • <td headers="c4">None</td> • <td headers="c5">Luecking</td> • </tr> <tr> <td headers="c1">212</td> <td headers="c2">5:45 pm &nbsp;- 9:00 pm</td> <td headers="c3">M</td> <td headers="c4">211</td> <td headers="c5">Carter</td> </tr> <tr> <td headers="c1">212</td> <td headers="c2">11:30 pm &nbsp;- 1:00pm</td> <td headers="c3">TR</td> <td headers="c4">211</td> <td headers="c5">Chan</td> </tr> </tbody> </table>

  13. Label Elements of Forms • <form action="Billing Info" method="post"> • <fieldset> <legend class-"TitleLarge"><b>Billing Information</b></legend><p> • <label for="firstname">First name (required):</label> • <input id="firstname" type="text" tabindex="1"></p><p> • <label for="lastname">Last name(required): </label> • <input id="lastname" type="text" tabindex="2"></p> • </fieldset> • </form>

  14. Skip Navigation

  15. Normal Page

  16. Alt Tags(None)

  17. Alt Tags (Descriptive)

  18. Other Vision Issues • Screen Magnifiers • Color Blindness: • 8% male population • 0.5% Female population • Most common red/green • Photo Sensitive Epilepsy

  19. Color Blindness This is an Ishihara plate commonly used to check for red/green color blindness

  20. Color Blindness This is what a red/green color-blind person might see. Note that the digit (3) is practically invisible.

  21. Mobility Impairments • Conditions with affect use of keyboard and mouse • Might be difficult, Might be impossible • Predictive typing • Speech recognition • Alternative input technology

  22. Hearing Impairments Few more issues: • Captioned media • Open or Closed captioning • American Sign Language

  23. Web Accessibility Initiative • Promote usability for people with disabilities • Goal of Universal Access • Set of guidelines which address 2 themes: • Graceful Translation • Make content understandable and navigable

  24. Web Accessibility Initiative Guidelines

  25. Globalization • Web is growing all over world • Number of Non English speaking users rapidly increasing • Usability issues involve use of language and culture • This processes is called globalization

  26. Global User Population

  27. Internationalization • Internationalization single design used world wide • Simpler text • Unambiguous display of number, currency, dates, and times • Isolate and remove culturally specific language

  28. Localization • Added cultural context • Translation of web page into local language • Relevant content

  29. Text and Translation • Translation: human or automatic? • Attention to writing style • Expression of dates, times • Express currency in local terms • Label units of measurements

  30. Languages Can Expand Labels

  31. Page Layout • Unicode for character support • Color issues • Icon issues (including flags) • Text Alignment (left vs. right)

  32. International User Testing • International and local sites need user testing • More involved than traditional • Test success of translation • International Inspection as alternative • Difficulties dues to language gap

  33. Personalization • Strategy for gaining competitive advantage • Added service for a user • Speeds task completion (I-Click) • Can require login • Cookies • Dynamic

  34. Privacy Concerns • No right to privacy in US • Privacy Contracts • Request of personal information can cause users to leave site • Highly related to trust

  35. Trust Many factors affect trust: • Context • Perceived Similarity • Standing in organization • Behavior • Certification • References

  36. Fostering Trust • Help establish credibility • Security Statement • Safe display of personal information • Use of secure servers • Confirmation of all costs • Confirmation of shipping address

  37. Controlling Privacy • No standard for enforcing privacy in place • P3P standard developed • Enforces and exposes site’s privacy policy • Tools to inform users of compliance with their selected privacy policy

  38. Trust (P3P)

  39. Trust (P3P)

  40. Privacy Bird

  41. Privacy Bird Shows Embedded Content

  42. Privacy Bird

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