UI Design Newsletter – December, 1999

Insights from Human Factors International

In This Issue Bob Bailey reviews:

Web Design Guidelines

What research-based guidelines are available for designing websites?

In the "User Interface Update – 1999" class, one of the in-class exercises was to have students identify the design guidelines that came from studies that were discussed in the class. The focus was on using research-based information to improve the user interfaces of websites. Each of the guidelines can be related to a research reference. These guidelines are summarized to the right.

General Design

• DO use ‘parallel design’ methods
• DO use multiple tools to design websites

Users and Tasks

• DO know clearly the intended use of the website by typical users – what features do they need (not want)
• DO NOT design for ‘first time users’ – unless that is your primary audience
• DO use ‘frequency of use’ of tasks as a major guide to appropriate decisions
• DO optimize high frequency (high priority) tasks – use ‘tiering’
• DO design for ‘ease of use’ not ‘ease of learning’
• DO clearly understand the profile of typical users, and make appropriate design decisions
• DO listen to users on functionality issues, but do not let users make design decisions – do not rely on users for good design decisions – ask users ‘what’ they do, not ‘how’ best to do it
• DO expect that there may be learning required to effectively use some websites
• DO determine whether users are ‘satisfiers’ or ‘performers’ and design accordingly
• DO design for ALL users, even those with handicaps (accessibility)
• DO design for the system configuration that is used by most users – on the Internet it is 17’ monitors 800 x 600 pixel resolution 56 kbps modems

Page Design – Specific

• DO design for breadth, not depth – ideally, require only ‘2 clicks to the content’
• DO NOT use a ‘splash page’ (wastes a click)
• DO minimize the use of ‘white space’ in search tasks
• DO have a descriptive, concise title for each page (to facilitate bookmarking)
• DO optimize reading speed by using black characters on a white background
• DO put a logo on every page
• DO use an area of about 780 x 430 pixels for a 800 x 600 pixel resolution page

Page Design -- General

• DO NOT require users to scroll navigation-only pages
• DO trade off total consistency for optimal performance
• DO limit ‘working memory’ requirements to around 4 items
• DO take all appropriate steps to minimize download time
• DO use meaningful labels for hyperlinks
• DO NOT waste time trying to find better fonts to increase reading speed or user acceptance – use commonly used and available fonts
• DO use ‘rapid serial visual presentation’ (RSVP) to increase reading speed of certain information
• DO include a ‘shopping list’ (highlighted terms) within pages found from a search
• DO go from ‘more’ items on the first page to ‘fewer’ items on the second page
• DO ‘physical integration,’ not ‘mental integration’ to improve performance
• DO minimize the number of bytes per page (minimize download time to no more than 10 seconds per page)
• DO NOT scroll text horizontally
• DO prioritize hyperlinks for users (important vs. less important)
• DO enhance the affordances of hyperlinks
• DO put the most frequently used hyperlinks toward the top of the page

Multimedia

• DO include appropriate sounds to improve both performance and preference
• DO use multimedia to improve both performance and preference
• DO NOT focus on increased ‘sparkle’ rather than good interaction
• DO NOT leave colors in graphics that are not used
• DO minimize use of extraneous (gratuitous) graphics
• DO use animation – but use it effectively

e-Commerce

• DO have sales in an e-commerce site – not just ‘everyday low prices’
• DO include ‘pictures, descriptive text and navigation buttons’ to increase sales
• DO NOT use banners to advertise – users tend to have ‘banner blindness’
• DO include a FAQ in an e-commerce application to help deal with increased ‘traffic’ (there is no relationship with increased ‘sales’)
• DO put banner ads close to content (if used)
• DO put banner ads near the page with the last navigation decision

Usability Testing

• DO design for (and usability test with) ‘impatient users’
• DO test design decisions on all recent versions (3.0 and newer) of both major browsers
• DO design to minimize ‘time on site’ for each user
• DO make design decisions to optimize either user performance or preference (user acceptance)
• DO use ‘performance measures’ when designing for performance

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