Developing a Dynamic Usability Framework for Spatial Domain Applications

1. Developing a Dynamic Usability Framework for Spatial Domain Applications Lei Cui and Monica Wachowicz Wageningen University and Research Centre Centre for Geo-Information The Netherlands E-mail: Lei.Cui@gmail.com

2. Contents • Introduction • Research questions • Methodology • Implementation • Results • Conclusions • Suggestions

3. Introduction • Usability • System usability comprises the extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use. [ISO 9241-11 standard on Display Screen (VDU) Regulations] • The context of use determines the types of users, tasks, equipment, and the physical and social environments in which the product is used.

4. Introduction • Usability elements and measures • Over 40 usability elements proposed in the literature; • For most of the usability elements, there is a lack of specified measures.

5. Introduction • Usability elements and measures • One approach has been proposed in the early 1990s and it is based on a hierarchical set of usability elements named as learnability, flexibility, and robustness. Measuring these elements is based on evaluating the experience of the user when interacting with the interface.

6. Introduction • Usability elements and measures • Other approaches have developed usability questionnaires which tend to cluster usability elements and measures such as speed, errors, time to learn, retention, flexibility, attitude, learnability, efficiency, retention, errors and pleasing ability, etc.

7. Introduction • Web mapping interfaces • Digital, interactive maps on the Internet • E.g. Map24.com, Mappy.com, 51ditu.com, etc.

8. Map24.com Mappy.com 51ditu.com(Lingtu Software, Co.) Introduction

9. Research questions • Which are the most suitable usability elements for comparing web mapping interfaces? • How usability elements can be measured in order to compare web mapping interfaces? • How users should be selected for a usability test?

10. Methodology • Define five interrelated components, which are users, tasks, interaction modes, measures, and usability elements. • Develop a framework to investigate the effects of map interactive displays on user satisfaction and familiarity across two types of commercial geoweb sites. • Incorporate the efficiency, effectiveness, and operability as usability elements within a spatial context.

11. Methodology

12. Methodology • Three tasks have been selected to allow users to search over a particular geographic location and return the results as a map image at a particular scale. • The framework dynamically assign the measures (time spent, number of interactions and number of errors occurred to users when performing tasks) to the six usability elements (familiarity, efficiency, effectiveness, error rates, operability and satisfaction).

13. Implementation • A survey questionnaire was assembled to gather information about the profile of the target user group, and the purposes and general use of the geoweb mapping applications. • The questionnaire was based on multiple choice answers which were related to three components of the usability framework (i.e. types of users, tasks, and interaction modes). • Sixty-two respondents replied the questionnaire out of 200 questionnaires sent out.

14. Implementation • Data collected were analyzed to formulate a usability test based on usability elements and measures. • The usability test was performed by eight users and the whole interview and user interaction with the interface were fully recorded.

15. Implementation • Usability testing • Users • Manager, planner, advisor, researcher, and student • Tasks • Task 1: Find route from Droevendaal, Wageningen to the city of Limmen by car • Task 2: Find the church in the city of Limmen • Task 3: Find route to pick up a friend in Vinkeveen • Web mapping interfaces • Map24.com • Mappy.com

16. Implementation • Usability testing • Measures • Time spent, number of errors, and number of interactions • Usability elements • Familiarity, efficiency, effectiveness, error rates, operability, and satisfaction

17. Implementation • Usability test set-up • Hardware • Laptop • Webcam • Software • Windows XP • Internet Explorer • TechSmith CamtasiaTM

18. Results • Usability of overall interface – Efficiency Average time spent

19. Results • Usability of overall interface – Familiarity Number of interactions per minute

20. Results • Usability of interactions • Zooming, panning, query, and printing Zooming Mappy.com Map24.com

21. Results • Zooming – Error rates Average number of errors

22. Results • Zooming – Operability by interaction styles Percentage of errors by interactions

23. Results • Usability of content • Map displays • “maps in Map24 have bigger size to provide a nice context of the location” • “maps in Map24 have more detailed information, comparing to Mappy in the same scale” • Route descriptions • “hard to read”, “too complicated”

24. Conclusions • The usability framework developed in this study worked well in the comparisons of the usability of different web mapping interfaces. • The main results of the usability test also confirm the dynamic characteristic of usability, and the important role of the framework for understanding and evaluating geoweb mapping applications.

25. Conclusions • Concerning the framework components: • “Operability” is the most representative usability element used in this study. • Among the three measures, “number of errors occurred” plays the most important role.

26. Conclusions • Concerning the framework components: • Better approaches are needed for selecting users from the target group for usability test. • Usability element “Satisfaction” is a complicated concept that needs to be understand more in future studies.

27. Conclusions • The study also shows that: • Clicking icon is the most usable interaction style for zooming; • And dragging map is of best usability for panning.

28. Suggestions • More research is needed to explore the potential classification of the framework components into hierarchies, where dynamic interrelations between sub-components can be defined through types of interaction modes. • The use of two commercial geoweb sites has suggested that there are more difficulties when employing the framework to understanding the content of interfaces, mostly due to the lack of studies on quantitative measures for content.

29. Questions!!

30. Methodology Errors/Time Errors/Interactions

31. Implementation • Example of the questions • Profession? Function? • What do you use maps on the Internet for? (news, weather forecasts, find location, find routes, find points of interest, collecting information for spatial planning)

32. Implementation