UKOLN is supported by:

1. SWMLAC Workshop: Accessibility and Usability Marieke Guy Interoperability Focus UKOLN is supported by: www.bath.ac.uk

2. What is Usability? Definitions: • the measure of a product's potential to accomplish the goals of the user • how easy an interface design is to understand and use • ability of a system to be used [easily or efficiently] • the people who use the product can do so quickly and easily to accomplish their own tasks

3. Assumptions Usability has multiple dimensions: • Usability means focusing on users • people use products to be productive • users are busy people trying to accomplish tasks • users decide when a product is easy to use Have a look at Janice (Ginny) Redish and Joseph Dumas, A Practical Guide to Usability Testing, 1999, p. 4

4. Critique • Are users always busy? Does this definition imply that usability is only present in the workplace?! • Effectiveness; Efficiency; Satisfaction • Do users always know when a product is ready? • Do all users agree about usability? • Is usability even measurable? • Is it a single characteristic?

5. Elements of Usability • Nielsen refers to five elements or components of usability: • learnability • efficiency • memorability • errors • satisfaction - Jakob Nielsen, Usability Engineering, 1993, p. 26 • These may not have equal importance in all cases.

6. Intentions and Goals • Usability depends on context: • What does the user want to do? • Who is the user? • What's the user's perspective on life? • Related to: • Internationalization: cultural, social • Task analysis: working out what the user wants to do (what the goal is), and how he or she would expect to be able to do it!

7. Goal: Reading your email • Some favourite subject lines • “Meeting time changed” (which one?) • “New version” (...of?) • “____________” (the 'Blank' mail) • “Hello” (...hi!) • These lack clarity • Example: 'Mystery Meat Navigation': interfaces which make you do the work...

8. Goal: Studying Music Therapy • ….at Augsburg - http://www.augsburg.edu/main.html • Hmm.... what's that nice bar on the bottom doing? What happens if I click on ... argh! It's moving! Umm... hey, there are words underneath. Maybe it's over there... moving too fast! Argh! I'll move the mouse off so I can read it! Oh... the words have disappeared... • And so forth

9. What’s up with these Sites?

10. Assessing Usability • Questionnaires • Heuristic Analysis • Cognitive walkthrough • Measuring the success of a Web site • User-centred design • Personas

11. Advantages Feedback from the user perspective Largely independent of context Can be used as base for comparison Quick and cost effective, generates a lot of data Disadvantages User expresses their reaction from their perspective - subjective topics are difficult Questionnaires usually don’t go into detail Looks like quantitative data, but provides only superficial understanding Questionnaires

12. Heuristic Analysis • Visibility of system status • Match between system and real world • User control and freedom • Consistency and standards • Error prevention • Recognition rather than recall • Flexibility and efficiency of use • Aesthetic and minimalist design • Help users recognise, diagnose and recover from errors • Help and documentation http://www.useit.com/papers/heuristic/heuristic_list.html

13. Heuristic Assesment • To do a heuristic assessment… • Take three to five evaluators and explain these heuristics to them • Ask each evaluator to examine the interface on their own and write down each place where the interface violates a heuristic • To make this easier, give the evaluator a typical usage scenario to follow

14. Heuristic Analysis • Doesn’t take long • Is simple to do • Finds most of the more obvious interface flaws • Requires only a few (3-5) unskilled evaluators to find ~90% of problems • Can also be used on mock-up interfaces, such as prototypes on paper or screenshots

15. Cognitive Walkthrough • ...is a practical evaluation technique that: • Can be performed in very early stages of prototyping, eg on paper • Quick and easy evaluation of designs, right from the start • Does not involve users - helps designers to see the system from the user’s perspective • Helps to identify problems in interacting with the system - procedural problems • Sessions can be videotaped for later analysis

16. Cognitive Walkthrough How well does the interface support exploratory learning? • Procedure • Set a goal to be accomplished with the system • Search the interface for currently available actions • Select the action that seems likely to make progress towards the goal • Perform the selected action, and evaluate the system’s feedback for evidence that progress has been made towards the current goal

17. Cognitive Walkthrough • Prerequisites: • information about the users’ knowledge and experience • about the expected uses of the system • a list of the expected ‘correct’ actions used to achieve each goal

18. What makes a Good Web site? • Depends on the site! But... • How many users visit the site? • How long do users spend on the site? • How many pages do they visit? • Do they achieve their aims?

19. Answers... • Users’ movements on your website are recorded as log files • From these we can see: • How many unique users visit • Where they came from - who referred them to our site • How long they spend on the site • What pages they visit • When (and perhaps why) they leave - maybe they all get stuck on the same page?

20. User-centred Design • Designing for the audience • An iterative process • Run the results past your users at each stage • Encourage user participation • Test early and often, even before any code exists - use paper prototypes • Add and test details each cycle

21. User Requirements • Usability testing reveals what parts of the user interface need to be fixed • Requirements analysis reveals the functionality that the program does not fulfil • User requirements can be used to inform design - to help the product approach users’ actual needs • Who are the users? • What are their goals and how can we help? • Expensive methods: task analysis • Discount method: making use of User personas

22. User Personas • Designing for real users is hard • Choose several in-depth user personas for whom to design • Based on real people, derived from qualitative research • Not based on a single individual • Helps us model software to likely user needs

23. Creating User Personas • Identify the target user groups • Research real people from those groups • Ethnography, interviews, diaries • Develop personas from the information gathered • Organise research data into descriptive text

24. Using Personas • Get to know the personas. • Write down their goals, their intentions • Write the story of how they would achieve their goal - the scenario • Determine the individual tasks or steps involved in this story • This represents a required feature set • Additionally, don’t be afraid to run ideas past them!

25. Acknowledgements • Thanks to my colleague Emma Tonkin for the content of these slides!

26. Questions • Any questions?