1. Agile Usability Jason Chong Lee Dept. of Computer Science Center for HCI Virginia Tech CS 3724: Introduction to HCI, November16, 2006

2. Introduction  Software Engineering Disasters  Agile Software Methods  Extreme Programming  What about Usability?  Making Usability Agile/Making Agile Usable  Extreme Scenario-Based Design Background OverviewApproachSBD+XPWrap-up

3. Software Engineering Disasters  Windows Vista Too many features Haphazard development Development “reset” in 2004-2005  FAA Advanced Automation System Cost overruns, delays and failures (1982-1994) $3-6 billion before project scrapped  Duke Nukem Forever Development begins in 1997 Two project resets, staff overturns

4. Software Engineering Disasters  Increasing complexity  Project mismanagement  Staff overturn  Changing and Ill-defined requirements  Miscommunication  …

5. Agile Software Development  We are uncovering better ways of developing software by doing it and helping others to do it. Individuals and interactions over processes and tools. Working software over comprehensive documentation. Customer collaboration over contract negotiation. Responding to change over following a plan.

6. Extreme Programming  Widely adopted agile development method Communication Simplicity Feedback Courage  One way of tackling problems of Software Engineering

7. XP Bottom Line… versus

9. What about Usability?  Concerned with: efficiency, effectiveness, learnability, ease of use, satisfaction  How are these addressed in agile methods? Customer = End User?  How can agile methods and usability play together?

10. Conflicts Usability EngineeringAgile Software Development Broad understanding of systemIncremental software delivery Needs of end userNeeds of clients Interface design and development System design and development

11. Agile Usability The integration of usability and agile development processes will lead to: Emergent development of interaction architecture Rapid and repeatable usability testing within constraints of agile development “depth-first” approach to interface design congruent with agile development

12. Key Issues to Address  Maintaining interface architecture through incremental development  Disseminating design goals & rationale between stakeholders  Usability evaluations in an agile framework  Accommodating ill-defined and changing requirements

13. Extreme Scenario-Based Design  Combine best practices of SBD and XP SE and UE concurrency Central Design Record to support communication Targeted usability evaluations within agile framework End Users Clients Agile Software Developers Usability Engineers CentralDesignRecord 21 3

14. UE and SE Concurrency Root Concept Scenarios, Claims User Stories Release Planning Iteration Small releases Acceptance Tests Usability Tests

15. Central Design Record  Common design representation shared by developers Derived from SBD and XP design artifacts Support communication among stakeholders Maintain interaction architecture coherency

16. Usability Testing  Light-weight analytic evaluations to test usability between iterations  Comprehensive empirical evaluations planned at each release cycle  Evaluations target only select areas of interface

17. SBD+XP Process Background Overview ApproachSBD+XP Wrap-up User Stories Acceptance Tests Feature Development Test Driven Development Project Scoping Release Iteration Acceptance & Usability Testing Summative Evaluation & Acceptance Central Design Record Root Concept Design Goals Claims & Scenarios Usability Tests

18. Contributions  Incremental approach to scenario- based design usable in agile development projects  More usable systems developed by agile development teams  Improved dissemination of design rationale between agile and usability professionals

19. Questions & Comments

20. References (1)  Auer, K., and Miller, R. Extreme Programming Applied: Playing to Win. Addison Wesley, Boston, MA, 2001.  Constantine, L. L., Process Agility and Software Usability: Toward Lightweight Usage-Centered Design. Information Age, 8 (2) 2002.  Bass, L., and John, B.E. Linking usability to software architecture patterns through general scenarios. Journal of Systems and Software 66(3), 2003.  Beck, K., Beedle, M., van Bennekum, A., Cockburn, A., Cunningham, W., Fowler, M., Grenning, J., Highsmith, J., Hunt, A., Jeffries, R., Kern, J., Marick, B., Martin, R.C., Mellor, S., Schwaber, K., Sutherland, J., and Thomas, D. The Agile Manifesto. 2001. Available at http://agilemanifesto.org  Beck, K. Embracing change with extreme programming. Computer. Oct. ’99. 32 (10), 70-77, 1999.  Lee, J. C., Chewar, C. M., and McCrickard, D. S. Image is Everything: Advancing HCI Knowledge and Interface Design Using the System Image. Proc. ACMSE 2005, Vol. 2, 376-381, 2005.  Lee, J. C., Wahid, S., Chewar, C. M., Congleton, B., and McCrickard, D. S.. Spiraling Toward Usability: An Integrated Design Environment and Management System. Technical Report TR-05-15, Computer Science, Virginia Tech, 2005.  Miller, L. Case Study of Customer Input for a Successful Product. In Proc. Agile 2005 Conference, 2005.

21. References (2)  Nelson, E. Extreme Programming vs. Interaction Design. Fawcette Technical Publications, 2002. http://www.fawcette.com/interviews/beck_cooper/. http://www.fawcette.com/interviews/beck_cooper/  Nielsen, J. Usability Engineering. Morgan Kaufman, San Diego, CA, 1993.  Patton, J. Improving on Agility: Adding Usage-Centered Design to a Typical Agile Software Development. In Proc. Second International Conference on Usage-Centered Design (forUSE 2003), 2003.  Payne, C., Allgood, C. F., Chewar, C. M., Holbrook, C., and McCrickard, D. S. Generalizing Interface Design Knowledge: Lessons Learned from Developing a Claims Library. Proc. IRI 2003, 362-369, 2003.  Preece, J., Rogers, Y., Sharp, H., Benyon D., Holland, S., Carey, T. Human-Computer Interaction. Addison-Wesley, Wokingham, England, 1994.  Rosson, M. B. and Carroll, J. M. Usability Engineering: Scenario-Based Development of Human-Computer Interaction. Morgan Kaufman, New York, NY, 2002.  Shneiderman, B., and Plaisant, C. Designing the User Interface. Addison Wesley, Boston, MA, 2005.  Wahid, S., Allgood, C. F., Chewar, C. M., and McCrickard, D. S. Entering the Heart of Design: Relationships for Tracing Claim Evolution. In Proc. SEKE 2004, 167-172, 2004.