Tutorials

The tutorial will explain how to set usability performance requirements based on effectiveness, efficiency and satisfaction, either to support internal communication or as part of a contract., and how to document them using the Common Industry Format. The tutorial is intended for practitioners and includes practical examples of how the approach has been implemented in industry.

PARTICIPANT KNOWLEDGE AND EXPERIENCE EXPECTED

The tutorial is intended for anyone wishing to gain practical experience of specifying usability requirements. Some previous experience of usability is desirable, but not essential, as the approach taken will be business-oriented. The tutorial is not aimed at researchers, and some aspects of the methods may be familiar to experienced usability practitioners.

GOALS FOR THE SESSION:

Participants in this tutorial will learn simple techniques that can be used to specify usability requirements based on:

• Identifying the range of contexts in which the product or system will be used
• Estimating task times for important scenarios of use
• Setting accuracy and completion criteria for important tasks
• Establishing satisfaction requirements
• Using the Common Industry Format to document usability requirements
• Identifying the key design issues that will impact on usability

By the end of the day participants will have sufficient knowledge to know how to introduce usability performance and satisfaction requirements into their own organisation.

Usability performance requirements link usability to business requirements for productivity and accurate work. The tutorial will also show how design issues can be identified that can help reduce the likelihood of usability errors and contribute to achieving the usability requirements.

HOW THIS TUTORIAL WILL BE CONDUCTED

The tutorial will be illustrated by case studies, and will include both class exercises and exercises in groups to apply the methods.
The audience will be split into groups determined by their major area of work: web, software development or hardware development. Each group will develop a case study through the tutorial. The warm-up exercise will be to brainstorm situations where usability requirements would be useful. Groups will nominate one of their members to define a real life product scenario they have worked on to give added realism to their case study. Groups will report the results of their exercises for class discussion.

TUTORIAL SCHEDULE WITH TIME ALLOCATION

1. Introduction to the Common Industry Format 40 mins

• Participant profiles; tutorial goals and overview

• What is the Common Industry Format?
• What is the Common Industry Format for Usability Requirements?
• class exercise: brainstorm situations where usability requirements would be useful
• Relationship between the Common Industry Format and international standards

2. Context of use 30 mins

• Specifying users, tasks and environments
• Why this matters: common mistakes
• class exercise: identifying the context of use

3. Task scenarios and task time 40 mins

• Writing meaningful scenarios
• Estimating task time
• Why this matters: common mistakes
• group exercise: writing scenarios

4. Accuracy and completeness 30 mins

• Identifying elements of the task output
• Estimating business impact
• Why this matters: common mistakes
• group exercise: setting requirements and estimating business impact

5. Satisfaction 10 mins

• Setting satisfaction criteria
  

6. Using requirements to improve communication 30 mins

• Internal communication and contractual requirements
  

DETAILED DESCRIPTION OF TUTORIAL

The following topics will be covered:

• The Common Industry Format for usability test reports has recently been made a US standard . A companion Common Industry Format for usability requirements has been produced, which can be used for internal communication or to specify requirements as part of a contract. The first exercise will be to brainstorm situations where usability requirements would be useful. This will be used to create a class-generated list.

• The importance of specifying the context of use, and how to use the Usability Context Analysis questionnaire to identify the range of intended users, tasks and environments, and to identify critical design issues.

• How to write meaningful task scenarios and estimate the associated task times.  How to write user-oriented scenarios, how to choose the right scenarios, how to estimate requirements based on information from existing systems, paper prototyping and step-by-step analysis.

• A structured method for estimating the extent to which user errors will reduce the accuracy and completeness of task output, and for assessing the magnitude of the resulting business costs. Identifying associated design issues. From a business perspective it is not the usability errors themselves that matter, it is the time and effort taken to correct detected errors and the business consequences of undetected errors.

• Specifying satisfaction requirements using psychometric questionnaires. Established questionnaires such as SUMI or QUIS can be used to baseline satisfaction requirements.

• Documenting usability requirements for internal use, or as part of a contract. The Common Industry Format for usability requirements can be used to communicate requirements internally, or to specify requirements as part of a contract. It also provides a basis for subsequent usability testing.

SPEAKER BIO

Nigel Bevan

Research Manager

Serco Usability Services

Dr Nigel Bevan is Research Manager at Serco Usability Services. He has first degrees in physics and psychology, and a PhD in man-machine interaction. He provides consultancy and training in usability and user centred design.

Nigel was technical co-ordinator of the EU MUSiC (Measurement of Usability in Context) project that produced methods for usability measurement. These methods have since been widely applied commercially. He was manager of the INUSE and RESPECT projects that set up a network of Usability Support Centres around Europe, the TRUMP project that incorporated user centred design into the development processes of two large organisations, the PRUE project that trialled use of the Common Industry Format for usability test reports, and the UsabilityNet project that has established a web site of usability resources.

He participates in several international standards groups where he has introduced the concept of quality in use. He contributed to ISO 13407 and the Common Industry Format, edited ISO 9241-11 (Guidance on usability), ISO/IEC 14598-1 (Evaluation of software quality - General guide), ISO/IEC 9126-1 (Software product quality model) and ISO/IEC 9126-4 (Quality in use metrics). He currently edits ISO/IEC25030 (Quality requirements) , ISO 20282-2 (Usability of everyday products), and the new Common Industry Format for usability requirements.

Nigel has given tutorials on usability, user centred design and requirements at international conferences including the Usability Professionals Association, CHI, Interact, HCI International and software quality and software engineering conferences.

He is a Board member of the Usability Professionals Association (UPA) and a council member of the UK UPA.