goals of info3315 learn about the range of techniques to: understand users establish requirements...

Goals of INFO3315

Learn about the range of techniques to:• Understand users• Establish requirements• Brainstorm alternatives creatively• Prototyping alternative• Evaluate these• Reflect on strengths and weaknesses of prototypes

Learn how to actually use a core set of these techniques

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User Centred Design

• Problem statements and situations of concern• Identifying user and their tasks• Requirements and one sentence statements • Systems analysis and design *• Creative exploration of concepts• Iterative prototype-based design

Plan for systems

Manage Design

Implement

SSMSoft Systems Methodology

Star MultiviewManagechanges

Implementationstrategy

Usabilitystudies

StrategicinformationSystemsplanning

Usabilityevaluation

Job design andtechnical support

PeopleWorkTechnology

OSTATask Analysis

Methods of user centred design (Eason in Preece)

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User-centred design elements

• make users central• users seen as people – in an environment– interacting with other people

• early testing and evaluation that involves users

• design iteratively

Simple illustrative example

Thought experiment:

Thought experiment:

Large and busy railway system with tickets sold solely by human ticket

sellers at each station.

Thought experiment:

Large and busy railway system with tickets sold solely by human ticket

sellers at each station.

Brainstorm on the situation of concern.

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Elements of SSM analysisSoft systems methodology

• Stakeholders• Who are the users• Who else needs to be considered• What else must be considered• … CATWOE

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SSM stagesreal world - abstraction

1. The situation of concern2. Expression of situation of concern3. Root definitions (CATWOE)4. Build conceptual models5. Compare 4 with 26. Feasible and desirable changes7. Action to improve situation

Situation of Concern

Thought experiment:

Large and busy railway system with tickets sold solely by a person at each station.

• There are long queues to buy tickets at peak hour. • There is a huge salary bill for ticket sales staff. • Being a ticket seller is considered a very dull job but is often

stressful in dealing with people who have been waiting a long time.

• There is often a mismatch in tickets sold and cash each day.• Elderly people really like buying tickets from a person.• Complex ticket options mean that a ticket seller can be really

helpful.• In times of high unemployment, ticket selling creates jobs.• Ticket sellers also improve passengers’ sense of safety at night

and when there are few people around.

CATWOE

1. Clients

• Who is on the receiving end?• What problem do they have now?• How will they react to what you are

proposing?• Who are the winners and losers?

CATWOE

2. Actors

• Who are the actors who will 'do the doing', carrying out your solution?

• What is the impact on them?• How might they react?

CATWOE

3. Transformation

• What is the process for transforming inputs into outputs?

• What are the inputs? Where do they come from?

• What are the outputs? Where do they go to?• What are all the steps in between?

CATWOE

4. Weltanschauung (Worldview)

• What is the bigger picture into which the situation fits?

• What is the real problem you are working on?• What is the wider impact of any solution?

CATWOE

5. Owner

• Can they help you or stop you?• What would cause them to get in your way?• What would lead them to help you?

CATWOE

5. Owner

• Can they help you or stop you?• What would cause them to get in your way?• What would lead them to help you?

CATWOE

6. Environmental constraints

• What are the broader constraints that act on the situation and your ideas?

• What are the ethical limits, the laws, financial constraints, limited resources, regulations, and so on?

• How might these constrain your solution?• How can you get around them?

CATWOE-info3315

• Checklist that is broadly useful• Helps broaden perspectives• Helps think about the people• And the other concerns• Informs definition of tighter interface and

system requirements• And the people appropriate for evaluation• Subject for A-4 sheet in exam

After identifying the transformation that you believe will help address the situation of concern

After identifying the transformation that you believe will help address the situation of concern

One sentence statement

One sentence statement (info3315)

A single sentence that states:• The users of the system• Description of the transformative interface

and system • Training level of the users• Time limits for completing task

One sentence statements (example)

A single sentence that states:• The users of the system (A member of the general public)• Training level of the users (without any training)• Description of the transformative interface and system

(will be able to buy a ticket at the automated ticket selling machine)

• Time limits for completing task (within 1 minute)A member of the general public without any training will be able to buy a ticket at the automated ticket selling machine within 1 minute.

Requirements

• Consider more user groups….• Consider different levels of training…• Consider different times associated with

these.• Consider variability among people.

Requirements

• Consider more user groups….– Elderly users– Children– Non-English speakers– People who are blind…

• Consider different levels of training…• Consider different times associated with these.• Consider variability among people.

One sentence statements (example)

A single sentence that states:• The users of the system (A member of the general public)• Training level of the users (without any training)• Description of the transformative interface and system

(will be able to buy a ticket at the automated ticket selling machine)

• Time limits for completing task (within 1 minute)A member of the general public without any training will be able to buy a ticket at the automated ticket selling machine within 1 minute.

Requirements

• Consider more user groups….• Consider different levels of training…– Regular user (expert)– First time user (novice)– Intermittent user– Discretionary user– People familiar with other ticket systems (existing mental

models for buying tickets)• Consider different times associated with these.• Consider variability among people.

One sentence statements (example)

A single sentence that states:• The users of the system (A member of the general public)• Training level of the users (without any training)• Description of the transformative interface and system

(will be able to buy a ticket at the automated ticket selling machine)

• Time limits for completing task (within 1 minute)A member of the general public without any training will be able to buy a ticket at the automated ticket selling machine within 1 minute.

Requirements

• Consider more user groups….• Consider different levels of training…• Consider different times associated with

these.• Consider variability among people.– Normal distributions

One sentence statements (example)

A single sentence that states:• The users of the system (A member of the general public)• Training level of the users (without any training)• Description of the transformative interface and system

(will be able to buy a ticket at the automated ticket selling machine)

• Time limits for completing task (within 1 minute)90% of the members of the general public without any training will be able to buy a ticket at the automated ticket selling machine within 1 minute.

A note about times

• These include recovery from errors• What if people fail to do the task at all?• How does one test a requirement that starts

“90% of people…..”

Goals of INFO3315

Learn about the range of techniques to:• Understand users• Establish requirements• Brainstorm alternatives creatively• Prototyping alternative• Evaluate these• Reflect on strengths and weaknesses of prototypes

Learn how to actually use a core set of these techniques