Chapter 18:  Methods for User Centered Design

Chapter 18: Methods for User Centered Design PowerPoint PPT Presentation


  • 119 Views
  • Uploaded on
  • Presentation posted in: General

User Centered Design. Development centered around involvement of user communityUsers should be involved in every aspect of design, including how implementation of new system will affect their work practices. Methods . K.D. Eason (1992) - 4 key stages to development. . . . . . . . . PeopleWorkTech

Download Presentation

Chapter 18: Methods for User Centered Design

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


1. Chapter 18: Methods for User Centered Design

2. 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

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

4. Methods Overview Four Approaches examined: Soft Systems Methodology (SSM) Open Systems Task Analysis (OSTA) Multiview Life Cycle Star Life Cycle

5. 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

6. 18.1 - SSM

7. 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

8. 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?

9. 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

10. 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

11. 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.

12. 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

14. 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

15. 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)

16. 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

17. 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

18. 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.

19. 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

20. 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

21. 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 don’t 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)

22. 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

23. 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)

24. 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)

25. 18.4 An HCI design approach Multiview’s rigid structure is good, but some system design efforts don’t 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

26. 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

27. 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

  • Login