a case study, your goal will be to expand and generalize theories (analytic generalizations) and not to enumerate frequencies (statistical generalization).” He further points out, “ Scientific facts are rarely based on single experiments; they are usually based on a multiple set of experiments that have replicated the same phenomenon under different conditions.”

We do not claim that our results generalize to all people in any particular group, not even provisionally. Neither do we claim that Sara is typical of any group, such as people who are blind or people with physical disabilities. However, there is nothing so particular about Sara that precludes these results from applying to others who might be similarly situated within their physical and social worlds.

Our focus on a single individual across a range of tasks and artifacts allowed us to seek coherence in the themes and patterns that spanned many aspects of her life, something we might have missed had we instead looked at a small range of tasks and artifacts across several individuals. Also, the range of tasks, including those involving both computational and non-computational artifacts, increases our confidence that we captured the key issues characterizing Sara’s interaction with technology. Enabling more access to technology may in fact require that we look at increasingly specific populations so as to tailor technologies more closely to people’s needs. However, our case study, with its rich data across a variety of interactions, provides a set of hypotheses that can be used comparatively in other studies.

Our second conclusion reiterates that it is the combination of functionality and socially situated meaning that determines who will use technology and how it will be used. Simply replacing one interaction mode, such as the display of text on a screen with a functionally equivalent mode as in speaking the text aloud, is not necessarily equivalent from the point of view of user experience. This is because functional equivalence might not account for the meaning of the mode of interaction for particular users in specific contexts. Efforts to provide multimodal support for people with perceptual and/or motor disabilities10, 22 are

encouraging, not simply because of the increased physico-cognitive support they provide. Rather, multimodal support offers the possibility of using different modalities on different tasks and in different contexts, but only if the designer allows this degree of user control of interaction mode.

Paradoxically, increasing and universalizing access to technology might require attending to the specific and situated meanings of technology use by particular populations in particular settings. Because technologies invisibly embed taken-for-granted assumptions concerning trade-offs in functionality, usability, and situated meaning, developing an understanding of these trade-offs for particular people and populations can improve technology access for increasing numbers of people.

Acknowledgments

We thank Sally Fincher for initial project brainstorming, key bibliographic references, and feedback on drafts; Genevieve Bell for helping overcome challenges in subject recruitment and for suggestions on carrying out ethnographic fieldwork; Lisa Tice for utilizing her professional network to help with recruitment; Mark Blythe for providing information on his protocols; Skip Walter and Eli Blevis for feedback and encouragement as we were completing our fieldwork; Donald Chinn and Carol Hert for support throughout; and Youn-kyung Lim for her many suggestions for improving the reporting of these results. And thanks most especially to Sara for her benevolence, sincerity, and willingness to share her life and to Laurie Rubin for her inspiration, motivation, and support.

This is a revised version of an earlier paper presented at the Ninth Interactional ACM SIGACCESS Conferences on Computers and Accessibility (Tempe, AZ, Oct. 15–17, 2007); http:// www.sigaccess.org/assets07/ and appears at http://portal.acm.org/citation. cfm?doid=1296843.1296873.

 

References

1. basso, k. Wisdom Sits in Places. university of new Mexico Press, albuquerque, nM, 1996.

2. bell, G., blythe, M., and sengers, P. Making by making strange: Defamiliarization and the design of domestic technologies. ACM Transactions on Computer-Human Interaction 12, 2 (June 2005), 149–173.

3. beyer, h. and holtzblatt, k. Contextual Design. Morgan

kaufmann Publishers, san francisco, Ca, 1998.

4. blythe, M., Monk, a., and Park, J. technology biographies: field study techniques for home use product development. In CHI02 Extended Abstracts on Human Factors in Computing Systems (Minneapolis, Mn, apr. 20–25). aCM, new york, 2002, 658–659.

5. bouvrie, J. and sinha, P. Visual object concept discovery: observations in congenitally blind children and a computational approach. Neurocomputing 70, 13–15 (aug. 2007), 2218–2233.

6. Csikszentmihalyi, M. and rochberg-halton, e. The Meaning of Things: Domestic Symbols and the Self. Cambridge university Press, Cambridge, u.k., 1981.

7. freud, s. Dora: An Analysis of a Case of Hysteria. Collier books, new york, 1963.

8. Geertz, C. The Interpretation of Cultures. basic books, new york, 1973.

9. harper, D. Working Knowledge: Skill and Community in a Small Shop. university of Chicago Press, Chicago, 1987.

10. Jacko, J., Moloney, k., kongnakorn, t., barnard, l., edwards, P., leonard, V., and sainfort, f. Multimodal feedback as a solution to ocular disease-based user performance decrements in the absence of functional visual loss. International Journal of Human-Computer Interaction 18, 2 (2005), 183–218.

11. kurniawan, s., sutcliffe, a., blenkhorn, P., and shin, J. Investigating the usability of a screen reader and mental models of blind users in the Windows environment. International Journal of Rehabilitation Research 26, 2 (June 2003), 145–147.

12. luria, a. The Man with a Shattered World: The History of a Brain Wound. harvard university Press, Cambridge, Ma, 1987.

13. Magnusson, C., rassmus-Grohn, k., sjostrom, C., and Danielsson, h. navigation and recognition in complex haptic virtual environments: reports from an extensive study with blind users. In Proceedings of Eurohaptics 2002 (edinburgh, u.k., 2002).

14. Mirel, b. Interaction Design for Complex Problem Solving. Morgan kaufmann Publishers, san francisco, Ca, 2004.

15. Moggridge, b. Designing Interactions. MIt Press, Cambridge, Ma, 2006.

16. Morley, s., Petrie, h., o’neill, a., and Mcnally, P. auditory navigation in hyperspace: Design and evaluation of a non-visual hypermedia system for blind users. Behaviour & Information Technology 18, 1 (Jan. 1999), 18–26.

17. newell, a.f. and Gregor, P. user-sensitive inclusive design—In search of a new paradigm. In Proceedings on the 2000 Conference on Universal Usability (arlington, Va, nov. 16–17). aCM Press, new york, 2000, 39–44.

18. spradley, J. Participant Observation. thomson learning, 1980.

19. u.s. Census bureau. Population Estimates 2000 to 2006; http://www.census.gov/popest/states/ nstannest.html.

20. Wall, s. and brewster, s. Providing external memory aids in haptic visualisations for blind computer users. In Proceedings of the Fifth International Conference on Disability, Virtual Reality, and Associated Technologies (oxford, u.k., sept. 2004).

21. Winograd, t. and flores, f. Understanding Computers and Cognition: A New Foundation for Design. ablex Publishing Corporation, nor wood, nJ, 1986.

22. Wood, J., Magennis, M., arias, e., Gutierrez, t., Graupp, h., and bergamasco, M. the design and evaluation of a computer game for the blind in the Grab haptic audio virtual environment. In Proceedings of Eurohaptics 2003 (Dublin, u.k., July 2003).

23. World Wide Web Consortium. Web Content Accessiblity Guidelines 1.0, 1999; http://www.w3.org/ tr/WCaG10/.

24. yin, r. Case Study Research, Design and Methods. Applied Social Research Methods Series, Vol. 5, Third Edition. sage Publications, thousand oaks, Ca, 2003.

 

Kristen Shinohara ( [e-mail]) is a Ph. D. student in the Information school of the university of Washington, seattle, Wa.

Josh Tenenberg ( [e-mail]) is Professor in Computing and software systems in the Institute of technology of the university of Washington, tacoma, tacoma, Wa.