Chapter 18: Methods for User Centered Design

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Chapter 18 Methods for User Centered Design
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User Centered Design

• Development centered around involvement of user
  community
• Users should be involved in every aspect of
  design, including how implementation of new
  system will affect their work practices

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Methods

• K.D. Eason (1992) - 4 key stages to development

Plan for System
People Work Technology
Design
Manage
Implement
Figure 18.1 Methods of user-centered design
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Methods Overview

• Four Approaches examined
• Soft Systems Methodology (SSM)
• Open Systems Task Analysis (OSTA)
• Multiview Life Cycle
• Star Life Cycle

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18.1 Soft Systems Methodology

• As all human actions take place within wider
  contexts, entire human-computer system needs to
  be understood
• Emphasis on gaining better understanding where
  perceived problems exist
• Not focused on finding solution, but the cause

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18.1 - SSM
f
7. Action to improve the situation
1. The Problem Situation
6. Feasible and desirable changes
2. Problem Situation Expressed
5. Comparison of 4 with 2
Real World
Abstract
3. Root definitions of the relevant systems
4. Building conceptual models
Figure 18.2 Stages in the soft systems
methodology.
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18.1 SSM

• Stages 1 and 2 are concerned with obtaining an
  expression of the problem situation
• Meetings held with all stakeholders of system
• Different points of views from all angles
  examined
• Reconciles the differences between the views

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18.1 Soft System Methodology

• Stage 3 - precise definition of the system
• Root definitions defined in terms of CATWOE
• Clients - Who benefits from the system?
• Actors - Who is involved with the system?
• Transformations - What does the system do?
• Weltanschauung (World View)
• Owners - Who commissioned the system?
• Environment - What conditions surround system?

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18.1 SSM

• Stage 4 - building conceptual models
• Modeling performed away from real world
• abstract representations separated from real
  world constraints
• Based on definitions from stage 3

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18.1 SSM

• Stage 5 - comparison of conceptual models to
  expressed problem situation
• Bring the model back out into the real world
• Gaps in root definitions exposed
• Analyst cycles back and adjusts definitions until
  all agree that they are sufficient

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18.1 SSM

• Stage 6 - Feasible and desirable changes
• As the comparisons between the model and the
  situation are being made, desirable changes are
  often uncovered
• Stage 7 - Actions to improve situation
• Further iteration of stage 6 as What can be
  done? is asked.

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18.2 Cooperative Design

• Participative design (a.k.a Scandinavian
  approach)
• argues that users should always be involved in
  the design of systems that they will be using
• Users analyze organizational requirements
• They plan appropriate social and technical
  structures that are to support the individual and
  organizational needs

"People don't resist changethey resist having
change imposed upon them." -
Merrelyn Emery
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"People don't resist change they resist having
change imposed upon them" -
Merrelyn Emery
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Sociotechnical Design

• Form of Cooperative design focused on developing
  complete and coherent human-computer systems
• Emphasis on social and technical alternatives to
  problems
• Human and organizational issues not considered
  separately from technology

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Sociotechnical Design

• System development is difficult, not because of
  the technical problems, but because of the social
  interaction when users and developers learn to
  create, develop and express their ideas and
  visions.
• -Greenbaum and Kyng
• (1991)

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Open Systems Task Analysis (OSTA)

• Method in understanding the relationships between
  the social system and the technical system
• Technical structure and functionality are
  specified alongside social system requirements
  (usability and acceptability)
• Understanding of the transformation that occurs
  when a system is introduced is the aim here

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Steps of OSTA

• 1. Primary Task - goals of group of workers
  are identified
• 2. Task inputs - usually come form outside the
  system, can affect system behavior
• 3. External Environment - includes physical
  environment, economic and political conditions
  and demand for output
• - ex. System that deals directly with public
  must deal with large variety of external
  conditions

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Steps to the OSTA

• 4. Transformation Processes
• Functions that must be undertaken to transform
  inputs into desirable outputs
• Object/Action flow chart constructed
• Data-flow diagram could be an example
• Hospital Diagram could involve patients as
  objects and performing operations and
  administering drugs as actions
• Relations between the functions also shown.

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Steps to the OSTA

• 5. Social System
• Roles of people in an organization analyzed in
  relation to each other
• Overall qualities that users possess are also
  listed
• 6. Technical System
• How the new system will be integrated with other
  systems and effects it will have on the nature of
  the work performed

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Still More Steps

• 7. Performance satisfaction
• Requirements outlined for social system when
  technical system is introduced
• 8. New Technical System
• Functionality aspects defined alongside usability
  and accessibility criteria
• Roles of technology and people, needed changes to
  overall system, training needs of staff, and
  interface issues all considered

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Problems with the OSTA

• Need for designers to guide the design process
  while keeping users informed
• Degree the OSTA can be integrated with other
  systems development efforts
• Designers dont always embrace the importance of
  user input
• Can only be used in suitable political and
  organizational climate
• Management commitment a must
• (most TQM efforts are bound to fail if this does
  not happen)

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18.3 Multiview methodology

• All-encompassing methodology which embeds soft
  and sociotechnical systems into a staged,
  controlled methodology where a specific order of
  events must be followed
• Begins with analysis of the human activities
• employs entity relationship and dataflow
  diagramming to design conceptual models before
  physical design begins

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Multiview methodology

• Primary Task Model (PTM) - definition of system
  purpose constructed after soft systems analysis
  (Stage 1)
• purpose of system
• stakeholders involved here
• Information analysis (Stage 2) the produces
  entity models, and a functional model (FM)

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Multiview Methodology

• Functional Model then used when designing the
  sociotechnical aspects (Stage 3)
• People Tasks (PT), Role Sets (RS), Computer task
  requirements (CTR) all designed here
• The Human-Computer Interface is designed (Stage
  4)
• Finally, the Technical aspects of system are
  designed (Stage 5)

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18.4 An HCI design approach

• Multiviews rigid structure is good, but some
  system design efforts dont fit into the
  framework easily
• Star model introduced as an alternative
• Derived from actual design practice
• Evaluation is the central process where all
  aspects are able to be examined by users and
  experts

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Star Life Cycle

• Where Multiview and other methodologies are
  top-down in nature, this methodology is more
  bottom-up where synthesis is happening rapidly
  and simultaneously with the top-down analysis.
• Rapid Prototyping with iterative development
  emphasized

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Star Life Cycle

• Development may begin at any stage
• requirements, design, and final product evolve
  gradually as more is known through trial and
  error
• important distinction between conceptual and
  physical design addressed
• What is required, what the system should do
  vs
• How the requirements are achieved