The design process

  • old users where available to learn difficult programs that would fulfill their needs
  • present users are experts in their work domain but not technicians
  • design should address their issues
  • 1991 - the Usability Professionals Association was born
  • LUCID - (Logical User-Centered Interaction Design) includes the observation of users, the development of real scenarios and of social impacts coming from using new systems
    Usability support

  • CUO - Chief Usability Officer, Usability Day, Usability Managers...
  • to stimulate change
    • note the difficulties of users, their mistakes...
    • evaluate peformance data on interfaces developed with LUCID
  • each project has its architect who develops the user interface and coordinates
    • human factors specialists
    • reads the technical literature,prepares budgets and deadllines
    • designs usability tests
    Specialization

  • today’s jobs narrow - we have specialists in:
    • interface development tools
    • data visualization strategies
    • use of sounds (voice synthesis, speech recognition)
    • technical writing, handbooks...
    Development tools

  • choosing the right tool is one basic step
  • new instruments speed up the implementation and favour the desig-test-refinement cycle
  • the writing of the guideline document is only the first step towards the implementation
  • management strategies, also called 3E (enforcement, exemption, enhancement) are spreading around
    Still on usability

  • it is always difficult to grasp the concept of usability (every change is costly)
  • it is also difficult to include the user’s requests in the project
  • Karat (1990, 1994) noted that for every single dollar spent on usability,100 US$ payoffs were obtained spread out along the following items:
  • reduced program development cost
    • reduced program maintenance cost
    • earning increse due to greater user satisfaction
    • efficiency and produttivity increase
    Other data

  • Landauer (1995) showed productivity increases up to 720% in projects that considered usability from the start
  • even minimal modifications of a project, after a usability test which pinpointed 20 of the most common errors, increased user efficiency from 19% up to a maximum of 80%
  • usability engineers become the real project managers, they also take care of resource allocation, costs and deadlines
    Design

  • design is typically creative and unpredictable
  • Carroll & Rosson (1985) describe design as follows:
    • design is a process, not being a state it cannot be described statically
    • design is non hierarchical,neither bottom-up nor top-down
    • deisgn is radically transformational; it requires the development of partial and temporal soutions which may also be eliminated during the overall design process
    • design also includes the discovery of new goals
    The three Pillars of Design

  • 3 pillars of design, each one produces a time gain of one order of magnitude
  • moreover, the system quality is improved
    First pillar

  • a set of working guidelines should be available from the start
  • 10 page document obtained from one week work from 2 persons
  • Macintosh was a good example of a generated guideline for programmers that easily read and understood what they had to do to maintain compatibility
  • Microsoft also has a document of this sort for implementors
    Guidelines

  • Words and icons
    • terminology (objects and actions), abbreviations, and capitalization
    • character set, fonts, font sizes, styles (bold, italic, underline)
    • icons, graphics, and line thickness
    • use of colour, backgrounds, highlighting, and blinking
  • Screen-layout issues
    • menu selection, form fillin, and dialog-box formats
    • wording of prompts, feedback, and error messages, justification, whitespace, and margins
    • data entry and display formats for items and lists
    • use and contents of headers and footers
  • Input and output devices
    • keyboard, display, cursor control and pointing devices
    • audible sounds, voice feedback, touch input, and other special input modes or devices
    • response times for a variety of tasks
  • Action sequences
    • direct manipulation clicking, dragging, dropping, and gestures
    • command syntax, semantics, and sequences
    • programmed function keys
    • error handling and recovery procedures
  • Training
    • online help and tutorials
    • training and reference materials
    Writing the guidelines

  • it is a social process to gain visibility and build support within an organization
  • controversial guidelines should be reviezed by colleagues or tesed
  • procedures to distribute the guidelines
  • ensure enforcement
  • allow exemptionspermit enhancements (the 3Es)
  • guidelines are a living text adapted to changing needs and refined through experience
  • acceptance may be increased by rigid standards, accepted practices and flexible guidelines
    How to use the guidelines

  • if properly written and provided at the beginning of the project, they may become an opportunity for discussion of controversial issues
  • implementation proceeds quickly and with few design changes
  • they announce policies for
    • enforcement - who reviews?
    • exemption - who decides?
    • enhancement - how often?
    User-interface s/w tools

  • both users and even designers have a vague idea of what the system will look like when built
  • once the system has been developed, major changes involve high cost and time
  • a realistic impression of the future system must be provided to the users
    • printed version of the proposed displays
    • on-screen display with an active keyboard & mouse
    • prototype of a menu may have only a few active paths...
    Prototypes

  • a form-fillin system may show the fields without processing them
  • paper models are also helpful
  • Hypercard and Macromind Director are good building tools for prototypes
  • Visual Basic and Borland’s Delphi are alos used
  • Visix’s Galaxy and Sun’s Java are more sophisticated
    Expert reviews and usability testing

  • theatrical producers know that previews to critics and extensive rehearsals are necessary for a good opening night
  • dress rehearsals are necessary with full cast, props and lighting
  • interactive system designers must carry out many small an some large pilot tests
  • expert review methods, tests with intended users, surveys, automated analysis tools, are all required
    Development methodologies

  • typical failure of s/w projects is of 60% !!
    • 25% never completed
    • 35% achieving partial success
  • due to lack of attention to design issues at the start
  • well designed systems are less expensive to develop and maintain
  • easier to learn and use and provide the users with a sense of mastery and confidence encouraging exploration
    Design in practice

  • formal methodologies have relieved the pain of deadlines and budgets for developers
  • usable interfaces are still something different...advocated by academics
  • improved methodologies for new hi-tech companies which have built from the original user-centered approach
  • detailed deliverables are specified incorporating cost/benefit and return on investment (ROI) analysis
  • moreover, management strategies - for schedule and budget - are also considered
    Logical user-centered design methodology: LUCID

  • formerly called QUE for quality Usability Engineering (Kreitzberg, 1996)
  • it identifies 6 differents stages
    1. develop product concept
    2. perform research and needs analysis
    3. design concepts and key-screen prototype
    4. do iterative design and refinement
    5. implement software
    6. provide rollout support
    Stage

    1
  • create a high concept
  • establish business objectives
  • set up the usability design team
  • identify the user population
  • identify technical and environmental issues
  • produce a staffing plan, schedule and budget

      Example of concept: The new home banking system will provide customers with unified access to their accounts. It will support balance inquiry, management of credit acounts and loans, transfer of funds, among acounts, electronic bill payment and investment in the bank’s family of mutual funds. The system will provide the custormer with year-end accounting for tax purposes.
    2
  • partition the user population into homogeneous segments
  • break job activities into task units
  • conduct needs analysis through construction of scenarios and participatory design
  • sketch the process flow for sequences of tasks
  • identify major objects and structures which will be used in the software interface
  • research and resolve technical issues and other constraints
    3
  • create specific usability objectives based on user needs
  • initiate the guidelines and style guide
  • select a navigational model and a design metaphor
  • identify the set of key screens: login, home, major processes
  • develop a prototype of the key screens using a rapid prototyping tool
  • conduct initial reviews and usability tests
    4
  • expand key-screen prototype into full system
  • conduct heuristic and expert reviews
  • conduct full-scale usability tests
  • deliver prototype and specification
    5
  • develop standard practices
  • manage late stage change
  • develop online help, documentation and tutorials
    6
  • provide training and assistance
  • perform logging, evaluation and maintenance
    Key screen prototype

  • one important feature of LUCID is the key screen prototype which - in participatory design sesions - is looked at with critical views conveying the system concept to the non-technical users
  • LUCID solicits user i/p, construct workflow scenarios and define the objects central to the design
  • the key screen prototype incorporates the major naavigational paths onf the system allowing the users to evaluate and refine it
  • it is also used for usability testing and heuristic review
  • key screens evoke strong reactions, generate early participation, create momentum for the project
    On LUCID

  • based on rapid prototyping, iterative usability testing
  • spots interface issues with have implications for the technical architecture of the product
  • LUCID describes a phased rollout approach built on theories of organizational change
  • LUCID makes committments to user-centered design and highlights the role of usability engineering in s/w development focusing on:
  • activities
    • deliverables
    • reviews
    Areas of activity

  • For each stage, 9 areas of activity are evaluated in connection with specified deliverables and timely feedback through reviews
    1. product definition
    2. business case
    3. resources
    4. phys. environment
    5. technical environment
    6. users
    7. functionality
    8. prototype
    9. usability
    10. design guidelines
    11. content materials
    12. documentation training and help
    LUCID conclusions

  • each project is different yet a design methodology is mandatory
  • validation & refinement in multiple projects has proven useful & constructive
  • LUCID promotes an orderly process and predictable progress

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