# Presentation: 337061

## Website usability

- Surprising findings from the research

**Bureau of Justice Statistics**

- Marianne W. Zawitz
- Sept. 25 - 27,  2000

## What is usability?

- “The measure of the quality of the user experience when interacting with something -- whether a traditional software application, or any other device the user can operate in some way or another.”

**Bureau of Justice Statistics**

- Jakob Nielsen *Devhead,* www.zdnet.com, 9/29/98

## Usability is measured by —

-  Ease of learning
-  Efficiency of use
-  Memorability
-  Error frequency and severity
-  Subjective satisfaction

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## The usability profession —

- From cognitive psychology
- Focused on Human Computer Interface (HCI)
- Initial work was testing software interfaces

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## What is usability testing?

- Researchers devise a series of tasks to accomplish based on the objectives of the software
- Subjects asked to perform the tasks in a laboratory setting
- Usually work with small number of subjects (6-8)

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## Usability techniques have been applied to the web

***Designing Web Usability***, Jakob Nielsen, 2000
***Web Site usability: A Designer’s Guide***, Spool, et al. 1997
- Keith Instone’s Usableweb (http://usableweb.com/)
-  many more in handout

**Bureau of Justice Statistics**

## Benefits of Usable Sites

- Reach a broader audience
- Facilitate move away from paper dissemination
- Users find the information they need
- Users don’t waste time or make errors
- Users are impressed with the sponsor
- Users return to the site and recommend it to others

**Bureau of Justice Statistics**

## Need for speed

- According to the Graphic Visualization and Usability Center’s 10 Survey (April 1999):
- Two thirds of respondents connected to the Internet at 56K or less

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## When asked “What do you find to be the biggest problems using the Web?” 

-  Slow ads were the most frequently reported problem
-  Speed came in a close second

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## What is the single most important issue facing the Internet?

-  Speed was second only to privacy

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## “...the Bandwidth problem will has not been solved in the last three years; nor will it be solved during the next three years.  Not until 2003 will high-end users have sufficient bandwidth for acceptable Web response times.  Low end users will have to wait until about 2008.”                            Jakob Nielsen, May 1999

- “...the Bandwidth problem will has not been solved in the last three years; nor will it be solved during the next three years.  Not until 2003 will high-end users have sufficient bandwidth for acceptable Web response times.  Low end users will have to wait until about 2008.”                            Jakob Nielsen, May 1999

## Tips for speeding up your site

-  Measure how long it will take for a page and its dependencies to download
-  Avoid unnecessary graphics particularly image maps
-  Reduce the number of colors in the graphics you do use
-  Use width and height specifications for all images

**Bureau of Justice Statistics**

## User behavior 

- Reading
- Scrolling
- Animation

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## Reading on the web is different than reading a document

-  Users scan content
-  In a study by Nielsen and Morkes
- 79% of users tested always scanned new pages
-  16% read word-by-word
- On screen reading is 25% slower than on paper

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## Legibility

- Text and background must have high contrast
- Avoid all caps
- Avoid text that is too small

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## Terminology

-  Users have difficulty with technical or domain specific terms
-  Users are unsure of where categories may lead especially if they are “cutsey”
-  Users hate “marketese”

**Bureau of Justice Statistics**

## Writing for the web involves —

-  “Chunking”
-  Inverted pyramid style with the conclusions first
-  Meaningful subheadings and keywords
-  Bulleted lists
-  One idea per paragraph
-  Half the word count than conventional writing

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## Users are willing to scroll

-  Need a reason to go down the page
-  The “fold” is not a constant
-  Users were just as likely to have their first click below the fold as above the fold

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## Animation is uniformly annoying

-  Users will ignore animated objects thinking they are advertisements
-  Many users will scroll down to avoid animations
-  Some users turn off animation in their browsers

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## Organization

-  Users have no patience with disorganized sites
-  In the Breadth Vs. Depth Battle, users prefer breadth (few clicks to content)

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## Navigation

-  Users don’t have a perceived mental model like they do with software
-  Shell structures with generic navigation do not work
-  Links with short titles do not work
-  Navigation needs to fit with content

**Bureau of Justice Statistics**

## Users need to know where they are

-  Users tend to go forward
-  When users navigate beyond four or five pages they forget how to get back
-  Using the same navigation on every page can confuse people
-  Differences in navigation based on context are helpful
- Indications of where they are help

**Bureau of Justice Statistics**

## Navigation bars

-  Users do better with navigation bars at the top or bottom rather than the side
-  Duplicated links on the left and bottom confused people
-  Clues that you were on a particular page on the nav bar were very helpful
-  Except for the home page, no more than 20% of the page should be navigation

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## Crumbs are a very useful device to show users where they are

- Home> Products >Publications> Order

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## Links for navigation

-  The number of links is negatively correlated with success in finding information
-  Users try to rule out links that are not going the right place
-  Users cannot remember more than 7 links

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## Other navigation devices

-  Users like Tables of Contents with sub-items to take them directly to content
-  A site map is helpful but not as good as a Table of Contents
-  FAQs frustrate users seeking specific information

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## Searching

-  About one third of the users in UIE’s study always went to the search facility
-  Users were often confused about what is covered by the search
-  Search results are often very confusing or lack information to tell the user what the link was

**Bureau of Justice Statistics**

## Links

-  Graphics
-  Color
-  Text
-  New title option
-  Embedded

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## Graphics do not work well as links

-  No indication that they are links
-  Visited links do not change color
-  If they are buttons they may not be big enough for the user to determine they are links

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## Users get confused when link colors are not standard

-  Unvisited links should be blue
-  Visited links should be reddish or purple
- Using standard colors means users don’t have to learn anything new

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## Users want to know what they are going to get when they link

-  7 - 11 word descriptions are most useful
- Anchors should be 3 - 4 words
-  Words must be informative to be useful
-  Use words users know; avoid ambiguity

**Bureau of Justice Statistics**

## Embedded links are harder to follow than separate links

-  Due to the way users scan the page
-  Use embedded links for contextual information rather than for navigation to information
- Don’t underline nonlink material

**Bureau of Justice Statistics**

## Graphics

- Do not help or hurt unless they slow you down
- Many users will not wait for a graphic unless they think it has content they want
- Always provide ALT tags for users who are browsing without graphics on or who use assistive devices

**Bureau of Justice Statistics**

## Reliability of information

- Users want too know who is presenting information
- Some users prefer to see the date of the last update
- Reputation managers are contributing to ensuring the reliability of information(eBay, Epinions, Google, Go)

**Bureau of Justice Statistics**

## Top 10 Mistakes of Web Design

**Frames**
**Bleeding-edge technology**
**Scrolling text and looping animations**
**Complex URLs**
**Orphan pages**
**Scrolling navigation pages**
**Lack of navigation support**
**Non-standard link colors**
**Outdated information**
**Slow download times**

**Jakob Nielsen’s Alertbox**

## Top 10 New Mistakes of Web Design

**Breaking or slowing down the back button**
**Opening new browser windows**
**Non-standard use of GUI widgets**
**Lack of biographies**
**Lack of archives**
**Moving pages to new URLs**
**Headlines that make no sense out of context**
**Jumping at the latest Internet buzzword**
**Slow server response times**
**Anything that looks like advertising**

**Jakob Nielsen’s Alertbox**

## Accessibility must also be considered a usability issue

- Many users --
- have disabilities
- are from foreign countries
- connect on slow modems or use older equipment and software

**Bureau of Justice Statistics**

## Quick tips for accessible sites

- Images and animations - Use ALT tag
- Image maps - Use client side image maps
- Multimedia - Provide text descriptions of all audio and video
- Hypertext links - Use text that makes sense - avoid “click here”
- Page organization - Use headings and lists and consistent structure

**Bureau of Justice Statistics**

## More quick tips for accessible sites

- Graphs & charts - provide a text description
- Scripts, applets & plugins - Provide alternatives
- Frames - Use Noframes and meaningful titles
- Tables - Make line-by-line reading sensible
- Check your work - validate

**Bureau of Justice Statistics**

## Accessibility resources

- W3C Web Content Accessibility Guidelines
- Unified Web Site Accessibility Guidelines - TRACE Center
- CAST’s Bobby
- Lynx viewer

**Bureau of Justice Statistics**