Usability and User-centred Design in the Software Development LifecycleShane Morris

A Little Bit About Me

Uni• Computer Science• Cognitive Science

I’ve Worked as:• User Interface Developer• User Interface Designer• Information Architect• Usability Engineer• Interaction Designer

I’ve worked on:• GUI’s•Web Sites•Web Applications• Kiosks• Interactive Multimedia• Hardware• Interactive Television

Now I’m a

User Experience Evangelist

I talk to...

I want to talk about

Usability and User-Centred Design in the Software Development Lifecycle

Usability

What do we mean by “Usable”?Easy to learn

Efficient

Error-free

Responsive

Accessible

Discoverable

Usability

“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

1998

Usability

“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

1998

10 Usability Heuristics – Jakob Nielsen

1. Visibility of system status

2. Match between system and the real world

3. User control and freedom

4. Consistency and standards

5. Error prevention

6. Recognition rather than recall

7. Flexibility and efficiency of use

8. Aesthetic and minimalist design

9. Help users recognize, diagnose, and recover from errors

10.Help and documentation

http://www.useit.com/papers/heuristic/heuristic_list.html

4. Consistency and Standards

4. Consistency and Standards

qantas.com

westpac.com.au

How do we achieve usability?Understanding users

Testing with users

User-Centred Design (UCD)

In order to design an application that is usable, we need to understand the users.

What is their...▪Prior knowledge / training▪Motivation and concerns▪Task and how they want to perform it▪Environment▪Tools and resources available

Every user interface design decision should be made with the end-users in mind.

You are not your user!

You are not your user

Adelaide Hospital

User Centred Design (UCD) Process

iso 13407: human-centered design process (simplified)

User

User Centred Design (UCD) Process

iso 13407: human-centered design process (simplified)

User

Usability TestingUsability testing is a formal method for assessing usability

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Usability Testing

http://www.catalystgroupdesign.com/cofactors/upload/InTestRoom1.jpg

Usability Testing – Key PrinciplesYou are too close to your own design to see the its inherent problems.▪(You are not your user)

Because usability testing is objective, it can be authoritative and powerful.

Don’t ask users what they think, observe what they do.

Usability Testing

http://www.portfoliodesign.net/clients/case_study/monster_mob_usability_testing.asp?nav=marketing>

During Usability Testing…

Individual representative users attempt typical tasks

Their actions are observed and logged▪Look for• Confusing aspects•Mistakes•When the need help

The sessions may be audio- and video-taped

Often participants are asked to ‘think aloud’

After (or during) sessions, participants are asked for additional subjective reactions, comments and suggestions

Usability Testing in Action

http://www.youtube.com/watch?v=SFwU_rvMBaE

Keys to Success

Plan and prepare thoroughly

Remain attentive and flexible, particularly during testing sessions

Because you are dealing with people, it’s important to behave in an ethical fashion, and treat participants with care and respect.

Be open to learning from the results.▪(Don’t use usability testing as a way to prove you were right)

Any problem a user finds with our software is our problem, not their problem.

Usability Testing

http://www.microusability.com/muservices/usability_testing.htm

Planning a Usability Test

Define the purpose▪Why are you testing?▪What are the success/fail criteria?▪What form of results do you need?(Success rates, completion times, error rates, satisfaction ratings?)

Write a test plan▪Surprises always arise during testing▪Testing uses ‘real people’ - it’s rare to get second chances

▪Identify, in detail, all materials required

Conduct a Pilot Test!

How many participants?

Statistical significance is generally not required

The first few participants tend to identify most of the major problems

Increasing the number of participants increases the workload and time required

Between 4 and 8 is a good rule of thumb.

Choosing Participants

Participants should be representative of the target users▪Right skills▪Right training

They should not be part of the project team!

Running the Usability Test

Introductions▪“This is not a test of you”▪Ask participant to “think aloud”▪Explain privacy considerations. •Will the session be recorded?• How will personal information be used?

Give user their (first) task▪Avoid the temptation to “lead” the participant.No: “What do you think the Print button would do?”Yes: “How would you get a paper copy of this?”

Repeat for any other tasks

Post-test Questionnaire

Task Cards

Participants are given a card describing each task they are to attempt

Completion Criteria

For each task, define a set of completion criteria – otherwise it’s impossible to report on success rates

Be very specific. ▪E.g. Completion means that a specific page was reached, or a specific goal was attained.

Tasks may be▪Completed successfully▪Abandoned by the participant▪Abandoned by the host

You should also keep tabs on whether assistance was required.

Observers

It’s a good idea to have observers

Observers must be silent and well-behaved

They are not allowed to interrupt

Test Laboratory

Extensive (and expensive) equipment is not necessary, but can be useful

Lab with one-way mirror (for observers)

Cameras

Scan converters

Mixing and editing capability

Comfort is an important consideration.

Usability Testing

http://www.cognizant.com/html/solutions/services/usability/services.asp

Reporting the Results

To get maximum results, you should spend time analysing and producing a formal report and presentation

Including video or audio in your report is a very powerful way to communicate the significance of issues found.

Remember to be diplomatic when reporting.

Usability Testing at Monash

Usabilty lab: a PC with a webcam that feeds video/audio into another conference room.

Currently 4 members in Usability and Accessibility services within Information Technology Services.

Work covers a wide range of products/projects, from designing UIs for custom built applications, to reviewing and redesigning websites used by students, staff and the general public, to improving both desk and web-based applications used by Monash staff to 'run the business'.

Conduct around 5 usability tests a year, using between 4 - 8 participants.

Usability Testing at Monash continued...Audio/video is captured using Morae and streamed into another conference room so that clients, stakeholders, etc. can observe sessions. Some of the projects that we've been involved in that students may be familiar with are designing the online version of the course handbooks, working on a redesign of the Course Finder search engine and related pages and usability testing the online application tool for international students.

Andrew SweeneyUsability Consultant

Monash UniversityITS Web Centre

Usability

“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

1998

Usability in the Software Development Lifecycle

Envisioning Planning Developing Stabilising Deploying