1 / 26

UKOLN is supported by:

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

jadzia
Download Presentation

UKOLN is supported by:

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  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?

More Related