Based mainly on Redmond-Pyle & Moore, GUIDE, Ch. 5 - Users and usability specification, and also on Alan Cooper's The Inmates are Running the Asylum.

Our slogans for today:

"The remarkable diversity of human abilities, backgrounds, cognitive styles and personalities challenges the interaction designer. A pre-schooler playing a graphic computer game is a long way from a reference librarian doing bibliographical searches for anxious and hurried patrons. Similarly a professional programmer using a new operating system is a long way from a highly trained and experienced air traffic controller. Finally, a student learning a computer-assisted instruction session is a long way from a hotel reservations clerk serving customers for many hours per day."

Ben Shneiderman, Designing the User Interface

What are the specific distinctions you can unpack from Shneiderman's neatly designed pairs of users?

They include at least:
 

• age
• domain experience
• computer experience
• degree of pressure
• frequency of use
• freedom of choice in system use
• direct vs indirect use

How to get a handle on users?

1. Identify who the end-users might be
2. Identify user classes
3. Identify relevant characteristics of user classes
4. Draw out implications of user characteristics for your design
5. Represent key users in order to keep user characteristics present for the design team during the process

• If you design for everyone you'll end up designing for no-one
• If you design for everyone you'll end up designing for yourself
• You will never be able to measure how usable your system is without an idea of the user (& task, & context)

• end-users vs managers/sponsors/purchasers/IT dept people
• direct vs indirect users

• in-house employees
• users of current manual system
• identified from marketing surveys & focus groups
• can you meet them? observe them? find out how they feel about their job, computers, the Web and whatever else is relevant
• can you read the marketing department's ideas or read transcripts of focus groups?

Can you identify user classes?

" - a sub-set of the total population if end-users who are similar in terms of their system usage and relevant personal characteristics"

e.g. for child's storybook, infant school teachers and parents probably form a single user class, but for a lesson planner system they would be quite distinct.

Use the GUIDE format to think about user classes and the implications of user characteristics for your design. Here are some forms partly filled out (more thinking needed throughout) for two fictional systems:
 
 

System: Hotel Room Booking System
User Class: Reception desk staff
Characteristic	Note on Characteristics	Requirements Implied
Type of user(Direct / Indirect / Remote / Support / etc).	Direct	installed at reception desk
Experience level of user(Novice / Intermediate / expert / transfer / intermittent)	Transfer	Look at previous sytem and preserve good aspects
Frequency of use of system	High, constant	must be ergonomically efficient
Use choice status (Mandatory / Discretionary)	Mandatory
Existing computer experience and skills	only booking systems
Other systems that they use (or will uses) concurrently	email, phone, cash till, credit card machine, minibar records, telephone records
Education / intellectual abilities	A-level

Motivation for using the system and specific goals	essential part of job a certain status attached
Number of users	8
Tasks performed (Cross-reference to task model)
General characteristics	Age: Sex:
Differences between users	minimal
Physical capabilities
Language issues
Extent of task knowledge needed	medium
Training on systems	as needed
Learning style Preference	Tutorial / Trial and error
Organizational position	n/a
How selected and promoted	n/a
Ways of working
Context (always important0	busy in mornings, standing up, using phone

 
 

System: Specialist French dance music CD web site
User Class: customers for music CD's
Characteristic	Note on Characteristics	Requirements Implied
Type of user Direct / Indirect / Remote / Support / etc.	Direct
Experience level of user	not known
Frequency of use of system	infrequent	must be instantly learnable
Use choice status	discretionary	can't afford usability problems
Existing computer experience and skills	not known
Other systems used concurrently	not known - mobile phone?	confirm/inform via text/phone?
Education / intellectual abilities	wide range
Motivation for using the system and specific goals	buy rare CD's, save time, be cool	appeal to specialist interest & look cool
Number of users	not known
Tasks performed	order, pay, browse, request info, add to mail list

General characteristics	Age: 16 - 30? Sex: mainly M?	young look and feel
Differences between users	peer group - strong identity	use identity
Physical characteristics / capabilities	fast reactions, good sight (colour blindness?)	font size, colours, animations?
Language issues	worldwide potential	English OK?
Extent of task knowledge needed	basic
Training they receive on systems	n/a
Learning style Preference	explore	help not appropriate
Organizational position	n/a
How they are selected and promoted	n/a
Ways of working	short bursts, interrupted, while watching TV etc.	has to be interruptible and interleavable

Where will this information be used?

• defining user requirements
• model user objects
• define style guide
• design interface
• evaluate the interface/system

Pin them to the wall, in the form of personas

For core user classes, describe a specific individual who might be central to that class

Define - gender, age, home life, background, hobbies, work role and so on.

Assign name and graphic - cartoon, photo, magazine cutout

Refer to the persona(s) rather than speaking about a user
 

Some personas for an academic conference Web site:
 

Skip Whitby heads a Research Program on Computer Mediated Communication at the University of Carpentaria in Northern Australia. Obviously he'd love to come to the conference, but departmental travel funds are tight this year. He's hoping to find a lot of useful information on the Web site.

Martin Jensen is a lecturer in Social Studies at the University of Lilleborg in Denmark. He may bring his girlfriend and 2 year old daughter with him and make a holiday of their time in the UK. The family are strict vegans. He's never been to the UK before and has no idea where Brighthelmstone is. Do you know where Lilleborg is? Well then…

Useful References on user descriptions

Look at Alan Cooper on user goals.

Richard Griffiths' notes on the GUIDE take on user classes