1. User requirements modelling: Motivation
Source: Textbook (Dix et al.), ch
Traditional SW lifecycle begins with Requirements Analysis:
Requirements elicitation
Requirements specification
Problem 1: usability issues may be neglected
Problem 2: may not get enough input from actual users
Problem 3: may fail to consider how new system fits into organization

2. User requirements modelling: 3 approches
Source: Textbook (Dix et al.), ch
Socio-technical models (ex. USTM/CUSTOM)
Soft Systems Methodology
Participatory Design

3. Socio-technical models
Source: Textbook (Dix et al.), ch
Examples: USTM/CUSTOM, OSTA, ETHICS
Considers both social (organizational) & technical issues
good technical solution can fail if we do not
take the social context into account
Important to identify all stakeholders, not just end users
Stakeholder: anyone effected by success/failure of system

4. Socio-technical model: USTM
Source: Textbook (Dix et al.), ch
USTM (User Skills & Task Match) /CUSTOM defines 4 categories of stakeholders:
Primary: use the system (ex. UNCG students using Genie to register)
Secondary: provide input or use output from system (ex. UNCG Registrars Office puts Fall course info into Genie)
Tertiary: others affected by success/failure (ex. UNCG administration)
Facilitating: designers/implementers/maintainers

5. Socio-technical model: USTM (2)
Source: Textbook (Dix et al.), ch
Process (can be time-consuming):
Describe organization (ex. its goals, political/economic background)
Describe all stakeholders (ex. their motivation, skills, power in organization)
Describe workgroups (groups of people who work together on task)
Describe what objects used for each task
Analyze stakeholder requirements in view of above

6. Soft Systems Methodology (SSM)
Source: Textbook (Dix et al.), ch
Another approach to user requirements modelling that considers the social context, including different stakeholder perspectives (“root views”)
Example: airline management’s perspective of new reservation system for travel agents
Clients (those who receive output or benefit): customer
Actors (those who perform activities within system): travel agents
Transformations (from input to output): customer’s need for transportation transformed to sale of seat on plane (and profit for airline)
Weltanschauung (world view of this perspective): increase profit through system efficiency
Owner (who controls system): airline management
Environment: airline regulations (local, national, international)

7. Participatory Design Another approach to user requirements modelling
Source: Textbook (Dix et al.), ch
Another approach to user requirements modelling
future users are members of design team
arguments for participatory design
since users know most about work context, more effective design will result from their active participation
if changes created by new system are not acceptable to users, then system will fail

8. Participatory Design (2)
Source: Textbook (Dix et al.), ch
Techniques to help users & designers communicate:
Brainstorming: goal is to come up with ideas from everyone and record them (do not judge them yet)
Storyboarding
Workshops: users tell designers about his/her work and designers tell users about technical capabilities
Pencil and paper exercises: ‘walkthrough’typical tasks using paper mock-ups of design

9. Adding HCI Methods to Traditional SW Lifecycle: Requirements Analysis
Analyze & document users’ current tasks: Task Analysis (ch. 7)
Gather & document requirements (especially non-functional requirements) for proposed system:
Usability specification (ch. 5)
User modelling: Socio-technical, Soft Systems, Participatory Design (ch. 6)
Validation (designing the right product) of user interface
Rapid prototyping (ch. 5)

10. Adding HCI Methods to Traditional SW Lifecycle: High-Level Design
Suggest/eliminate ideas for design of user interface:
Task Analysis, Usability specification (Use documents created by these methods during Requirements Phase)
Participatory Design (Users continue working on design team after Requirements Phase) (ch. 6)
Dialogue design notation (STN) (ch. 8)
Interaction Paradigms (ch. 4), Design guidelines (ch. 5)
Validation (designing the right product) of user interface
Rapid prototyping (ch. 5)