Скачать презентацию e TEN Tenuta support action Usability and accessibility Скачать презентацию e TEN Tenuta support action Usability and accessibility

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e. TEN Tenuta support action Usability and accessibility of educational web sites Nigel Bevan e. TEN Tenuta support action Usability and accessibility of educational web sites Nigel Bevan [email protected] com University of York UK 1

How Usable are current systems ? o UK Passport Office n n n o How Usable are current systems ? o UK Passport Office n n n o New software for issuing passports took operators twice as long Caused delays of up to 3 months in obtaining a passport Huge cost of additional clerical staff E-commerce web sites n User success in purchasing ranges from 25%-42% 2

ISO 9241 -11 Guidance on Usability o Usability is more than the user interface ISO 9241 -11 Guidance on Usability o Usability is more than the user interface n Usability: The extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use n Effectiveness: The accuracy and completeness with which users achieve specified goals. n Efficiency: The resources expended in relation to the accuracy and completeness with which users achieve goals. n Satisfaction: The comfort and acceptability of use 3

Why this matters o Usability is about meeting user needs o Two types of Why this matters o Usability is about meeting user needs o Two types of educational user: student and instructor n Effective: success in achieving navigational and educational goals n Efficient: can be completed in an acceptable amount of time n Satisfied: willingness to use the system 4

How do you achieve usability? o ISO 13407 Human-centred design process for interactive systems How do you achieve usability? o ISO 13407 Human-centred design process for interactive systems o Principles of user-centred design n understand the users and their tasks evaluate prototypes with users iterative development 5

Understand users and the context of use o o The usability of a product Understand users and the context of use o o The usability of a product is affected not only by the features of the product itself but also by its Context of Use Context is the characteristics of: n n the users of the product any disabilities the tasks they carry out the technical, organisational and physical environment in which the product is used 6

Why is usability important? o Focus on user needs n n n o reduce Why is usability important? o Focus on user needs n n n o reduce development times lmprove effectiveness simpler interface, fewer user errors Reduce development costs by: n n Producing a product that has only relevant functionality Detecting and fixing usability problems early in the development process Minimizing or eliminating the need for documentation and training Reducing the risk of product failure 7

Accessibility o Default industry “standard” is the Web Content Accessibility Guidelines (WCAG) n o Accessibility o Default industry “standard” is the Web Content Accessibility Guidelines (WCAG) n o 14 Guidelines (e. g. “Provide equivalent alternatives to auditory and visual content”) n o Developed by the Web Accessibility Initiative (WAI) of the World Wide Web Consortium (W 3 C) 65 checkpoints WCAG 1 is the basis of a number of other accessibility guidelines n n n e. GIF document of the UK government, Section 508 of the Rehabilitation Act (USA), EU Action Plans (e. g. e. Europe 2002, 2005) 8

Priorities o Checkpoints are grouped into three levels of importance (= Priority levels in Priorities o Checkpoints are grouped into three levels of importance (= Priority levels in WCAG speak) n n n o Priority 1 (level A accessible): A Web content developer must satisfy this checkpoint. Otherwise, one or more groups will find it impossible to access information in the document. Priority 2 (level AA accessible): A Web content developer should satisfy this checkpoint. Otherwise, one or more groups will find it difficult to access information in the document. Priority 3 (level AAA accessible): A Web content developer may address this checkpoint. Otherwise, one or more groups will find it somewhat difficult to access information in the document. But WCAG accessible does not necessarily mean usable! 9

Tools o WAI recommends doing manual checks for accessibility and using 2 general tools Tools o WAI recommends doing manual checks for accessibility and using 2 general tools on a selection of pages from a website. o A particularly useful meta-tool is the Web Accessibility Toolbar n o www. visionaustralia. org. au/ais/toolbar An accessibility audit of about 30 pages of a large website with the Toolbar takes about 30 person hours of work (about 80 individual checks per page) 10

Main accessibility issues A UK study showed that 80% of accessibility problems are covered Main accessibility issues A UK study showed that 80% of accessibility problems are covered by 10 WCAG 1 checkpoints 1. Provide text equivalents for non-text elements 2. Ensure that foreground and background colour combinations provide sufficient contrast when viewed by someone having color deficits or when viewed on a black and while screen 3. Ensure that pages are usable when scripts, applets or other programmatic objects are turned off or not supported. If this is not possible, provide equivalent information on an alternative accessible page. 4. Avoid movement in pages (until user agents allow users to freeze moving content) 11

Main issues continued 5. 6. 7. 8. 9. 10. Do not cause pop-ups or Main issues continued 5. 6. 7. 8. 9. 10. Do not cause pop-ups or other windows to appear and do not change the current window without informing the user (until user agents allow users to turn off spawned windows). Divide large blocks of information into more manageable groups where natural and appropriate. Clearly identify the target of each link. User the clearest and simplest language appropriate for a site’s content. Ensure that text size values are relative rather than absolute. Use navigational mechanisms in a consistent manner. 12

Evaluation with users o Essential to observe users trying to use your system n Evaluation with users o Essential to observe users trying to use your system n o Create a typical usage situation n n o Demonstration is not enough! Ask the user to carry out their tasks without any assistance and to think aloud Do they understand what to do? Do they follow the intended sequence? Are their problems fort users with disabilities? If possible test at least 5 users o o But any better than none! One user test of an e. TEN project n “It is so longwinded I would never use it in a million years!” 13

o www. usability. gov/pdfs n n Free download $35 book 14 o www. usability. gov/pdfs n n Free download $35 book 14

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7. Navigation 16 7. Navigation 16

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10. Links 18 10. Links 18

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10. Links 20 10. Links 20

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10. Links 22 10. Links 22

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12. Lists 24 12. Lists 24

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Tenuta Support for e. TEN projects o Training courses for usability and accessibility n Tenuta Support for e. TEN projects o Training courses for usability and accessibility n Genoa, 6 February n Madrid, 2 days in mid April o On-site support for e. TEN projects to review their e-solutions o More information: www. etenuta. org 26