User interface design for the Web Engineering Psychology


Published on

Describes why usability is important for the Web, challenges when designing for the Web, and a Web user interface design process.

Published in: Technology, Design
  • Be the first to comment

  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

User interface design for the Web Engineering Psychology

  1. 1. User Interface Design for the Web Lawrence Najjar [email_address]
  2. 2. Outline <ul><li>Why usability is important </li></ul><ul><li>Challenges for designing Web-based user interfaces </li></ul><ul><li>Web user interface design process </li></ul>
  3. 3. Why Usability is Important <ul><li>Biggest problem with Web is download time 1 </li></ul><ul><li>Second biggest reason people don’t buy from Web site is navigation difficulties 2 </li></ul><ul><li>28% of Web shoppers surveyed had trouble finding the product they wanted 3 </li></ul><ul><li>83% of Web shoppers surveyed left a site due to bad performance, especially poor navigation and slow downloads 4 </li></ul><ul><li>62% of Web shoppers surveyed gave up looking for a product online 3 </li></ul><ul><li>Dissatisfied customers tell about 10 others 5 </li></ul>
  4. 4. Why Usability is Important (continued) <ul><li>If usability improved, sales can improve </li></ul><ul><ul><li>IBM sales increased 400% after site redesign 6 </li></ul></ul><ul><ul><li>Digital Equipment Corporation found 80% increase in revenue 7 </li></ul></ul><ul><li>One study 8 estimated that improving the customer experience increases conversion rate by 40% and increases order size by 10%. </li></ul>
  5. 5. Challenges for Designing Web-based User Interfaces <ul><li>Short download times </li></ul><ul><li>Limited interaction options (ex. no drag-and-drop) </li></ul><ul><li>Broad user population </li></ul><ul><li>Impatient users </li></ul><ul><li>Many application choices </li></ul><ul><li>Diverse interaction hardware and software </li></ul><ul><li>Multiple languages </li></ul><ul><li>Disabled users </li></ul>
  6. 6. Web User Interface Design Process <ul><li>Define users </li></ul><ul><li>Define functional requirements </li></ul><ul><li>Write use cases </li></ul><ul><li>Develop site diagram </li></ul><ul><li>Build interactive wireframe mockup </li></ul><ul><li>Test usability </li></ul><ul><li>Write functional design specifications </li></ul><ul><li>Perform acceptance test </li></ul>
  7. 7. 1. Define Users <ul><li>Develop user profile </li></ul><ul><li>Perform experience architecture </li></ul><ul><li>Create personas and scenarios </li></ul>
  8. 8. User Profile Facility Managers Gender Generally male Age 30 to 50 years old Education High school graduate Income $25,000 to $45,000 per year Location Facility manager office in office building Computer experience Moderate. Facility manager uses computer for e-mail and researching products on the Web Computer IBM-compatible personal computer Web connection Slow connections (56K modem) Objectives Want to save time, reduce costs of running facility, monitor security, and control specific equipment as needed.
  9. 9. Experience Architecture Intent Audience Context Learn about products Solve problems Get entertained Home Work Tech expert Tech novice Gadget lover
  10. 10.
  11. 11. 2. Define Functional Requirements <ul><li>Identify functional requirements </li></ul><ul><ul><li>Ask client </li></ul></ul><ul><ul><li>Ask users – focus groups, interviews, contextual inquiry, questionnaires </li></ul></ul><ul><li>Prioritize functional requirements </li></ul><ul><li>Select functional requirements </li></ul><ul><li>Get client approval </li></ul>
  12. 12. Functional Requirements Function Description Priority Register Enter registration and personalization information Low Search Find product High Browse Browse catalog for product High
  13. 13. 3. Write Use Cases <ul><li>Identify use cases </li></ul><ul><li>Prioritize use cases </li></ul><ul><li>Scope use cases </li></ul><ul><li>Select use cases </li></ul><ul><li>Get client approval </li></ul>
  14. 14. Use Cases Use Case Task Flow Description User Preference Differentiation from Competitors Technical Difficulty Show confirmation Provide confirmation when user adds, edits, or erases registration Medium Low Low Remove confirmation Take the confirmation off the page Low Low Low Change registration Edit user’s reg. information Medium Medium Low Remove registration Erase user’s registration Low High Low Function Description Priority Register Enter registration and personalization information Low
  15. 15. 4. Develop Site Diagram <ul><li>Identify sections and subsections </li></ul><ul><li>Name sections </li></ul><ul><li>Iterate with client </li></ul>
  16. 16. Site Diagram
  17. 17. 5. Build Interactive Wireframe Mockup <ul><li>Show how functions may work 9 </li></ul><ul><li>Don’t show graphics </li></ul><ul><li>Don’t use raw HTML </li></ul><ul><li>Don’t connect to databases or other tools </li></ul><ul><li>Iterate with client </li></ul><ul><li>Make changes quickly and cheaply </li></ul>
  18. 18. Interactive Wireframe Mockup
  19. 19. 6. Test Usability <ul><li>Add graphics to several typical task pathways </li></ul><ul><li>Recruit five representative users </li></ul><ul><li>Ask users to try to perform typical tasks </li></ul><ul><li>Record problems </li></ul><ul><li>Ask participants to complete questionnaires </li></ul><ul><li>Fix interactive wireframe mockup </li></ul><ul><li>Repeat </li></ul>
  20. 20. Usability Test
  21. 21. 7. Write Functional Design Specifications <ul><li>Capture image of functional design of each page </li></ul><ul><li>List each control </li></ul><ul><li>Describe how each control works </li></ul>
  22. 22. Functional Design Specifications <ul><li>Global buttons – top navigation bar </li></ul><ul><li>GE Home - links to the GE Home page at </li></ul><ul><li>Customer Center Home - links to the Power Systems customer center at </li></ul><ul><li>Sales and Service Home - links to the GE Power Systems Sales and Service home page </li></ul>
  23. 23. 8. Perform User Acceptance Test <ul><li>Use actual pre-launch site </li></ul><ul><li>Ask representative users to perform typical tasks </li></ul>
  24. 24. Conclusion <ul><li>Web usability is important </li></ul><ul><li>A user interface design methodology can help improve usability </li></ul><ul><li>The real world is different from the academic world </li></ul>
  25. 25. References <ul><li>1 Graphics, Visualization, and Usability Center (1998). GVU’s 9th WWW User Survey. Atlanta: Georgia Institute of Technology, College of Computing, Graphics, Visualization, and Usability Center. Available: </li></ul><ul><li>2 Kadison, M. L., Weisman, D. E., Modahl, M., Lieu, K. C., and Levin, K. (1998, April). On-line Research Strategies: The Look to Buy Imperative. Forrester Report, 1 (1). Available: http://www. </li></ul><ul><li>3 Seminerio, M. (1998, September 10). Study: One In Three Experienced Surfers Find Online Shopping Difficult. Inter@ctive Week. Available: 981007b.html </li></ul><ul><li>4 Thompson, M. J. (1999, August 9). How to frustrate Web surfers. Industry Standard [On-line]. Available:,1283,956,00.html </li></ul><ul><li>5 Albrecht, K. & Zembre, R. E. (1985). Service America. New York: Warner. </li></ul><ul><li>6 Tedeschi, B. (1999, August 30). Good Web site design can lead to healthy sales. New York Times e-commerce report [On-line]. Available: </li></ul><ul><li>7 Wixon, D., & Jones, S. (1992). Usability for fun and profit: A case study of the design of DEC RALLY version 2. Internal report, Digital Equipment Corporation. Cited in Karat, C., A business case approach to usability cost justification. In Bias, R. G., & Mayhew, D. J. (1994). Cost-justifying usability. San Diego: Academic Press. </li></ul><ul><li>8 Creative Good (2000, June 12). The dotcom survival guide. Creative Good [On-line]. Available: </li></ul>
  26. 26. References (continued) <ul><li>9 Najjar, L. J. (2000). Conceptual User Interface: A new tool for designing e-commerce user interfaces . Internetworking, 3.3 [On-line]. Available: </li></ul>
  27. 27. Additional Readings <ul><li>Najjar, L. J. (1990). Using color effectively (TR 52.0018). Atlanta, GA: IBM Corporation. Available: </li></ul><ul><li>Najjar, L. J. (1999, June). Beyond Web usability . Internetworking, 2.2 [On-line]. Available: </li></ul><ul><li>Najjar, L. J. (in press). E-commerce user interface design for the Web. In Proceedings of 9 th International Conference on Human-Computer Interaction. Mahwah, NJ: Lawrence Erlbaum. Available: </li></ul><ul><li>Nielsen, J. </li></ul><ul><li>Nielsen, J. (2000). Designing Web usability. Indianapolis: New Riders. </li></ul>