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Exploratory Methods

Here is a brief summary of some methods that can be used to help designers understand design problems. (Based on [Jon92])

Stating Objectives

  1. Identify the situation within which the design is to operate.
  2. Identify features of this situation with which the design must be compatible if it is to be accepted by sponsors. Compatibility with these features is the ultimate objective. They include:
    • the sponsors' expectations and the reasons for them
    • the resources available
    • the essential objectives
  3. Ensure that statements identifying the objectives are compatible with each other and with information that becomes available while designing.

Literature Searching

  1. Identify the purposes for which published information is being sought.
  2. Identify the kinds of publication that are likely to contain information that can be relied upon for such purposes.
  3. Select the most relevant of the standard methods of beginning a literature search, such as
    • encyclopedias and other reference texts
    • library catalogues, journal abstracts, and indices
    • librarians and industrial information experts
    • individual experts by phone, email, post, interview, etc
    • personal network of colleagues
  4. Minimize the search cost by allowing for retrieval delays and by continuously evaluating both the choice of sources and the applicability of collected data
  5. Keep accurate and complete references to documents that are found to be usable
  6. Keep local collections of publications sufficiently small and temporary to permit rapid retrieval (somewhat obsolete with respect to massive online sources currently available)

Searching for Visual Inconsistencies

  1. Examine samples and photographs of existing designs.
  2. Identify apparent inconsistencies and contradictions in the arrangement and purposes of design components.
  3. Infer reasons for these inconsistencies and look for evidence of causes of design change.
  4. Envisage ways of removing inconsistency and of adapting to the inferred external causes of change.

Interviewing Users

  1. Identify user situations that are relevant to the design situation that is being explored
  2. Seek the agreement of all the persons within the user situation who could be affected by the interviewer's presence or by a new design
  3. Encourage users to describe and to demonstrate any apsects of their activity that are important to them
  4. Direct the conversation toward aspects of the user's activity which seem relevant to the situation that is being explored
  5. Record both circumstantial and critical findings during the interview or within a short time of it
  6. When appropriate, obtain the user's comments on the conclusions drawn from an interview


  1. Identify the design decisions that are to be influenced by replies to the questionnaire
  2. Identify the kinds of information that are critical to the taking of these decisions
  3. Identify the kinds of people who have rapid access to the kinds of information needed
  4. Carry out a pre-pilot investigation to gain insight into the knowledge of potential respondents
  5. Write a pilot questionnaire that fits both the known principles of questionnaire design and the particular situation, including
    • Ask for the minimum information needed for the purpose at hand
    • Ask questions that the intended respondents are able to answer
    • Require simple yes/no, or numeric, or multiple-choice style, answers
    • Ask questions most likely to be answered truthfully and without bias
    • Do not be unnecessarily inquisitorial (think of ridiculous “government forms”)
  6. Circulate the pilot questionnaire to test the questions, the variability of the answers, and the method of analysis
  7. Select an appropriate sample of the kind of people having rapid access to the information that is sought
  8. Administer the questionnaire
  9. Extract from the replies the data most helpful to designers

Investigating User Behaviour

  1. Consult and observe experienced and inexperienced users of similar equipment before designing the new
  2. Carry out a man-machine systems analysis to define tasks, user abilities, and the design requirements for interfaces (the parts of the product that affect users)
  3. Observe or simulate critical aspects of the behaviour of both skilled and unskilled users of the proposed design
  4. Record limiting values which must not be exceeded if users are to carry out the actions required without error, injury, or discomfort

Systemic Testing

  1. Identify the features of the existing situation that are not as desired
  2. Identify sources of highly variable behaviour within the existing situation
  3. Apply or relax gross constraints to these sources of variability and record the effects upon the features that are not as desired – record also the effects upon other features in the situation
  4. Select the most promising and the least harmful of the tested constraints as an avenue for planning and achieving the desired changes

Selecting Scales of Measurement

  1. Pose the questions that are to be answered by measurement
  2. Determine the acceptable error and the acceptable cost of measurement
  3. Select an appropriate measurement scale – there are six
    1. Nominal – colours, nationalities, smells, professions, area codes
    2. Partial order – ordered by single of few of all possible criteria
    3. Ordinal – absolute ordering by rank
    4. Interval – degrees centigrade
    5. Rational – metres, dollars, ohms
    6. Multi-dimensional – mpg, mental age, force
  4. Plan the measuring procedure to be compatible with the above

Data Logging and Data Reduction

  1. Identify the uncertainties that are critical to the success or failure of the range of design options under consideration
  2. Identify the degree to which critical uncertainties have to be reduced
  3. Identify the time and resources available for reducing critical uncertainties
  4. Review the available methods of data logging and data reduction, noting, in each case, the accuracy, speed, cost and the kinds of question that can be answered
  5. Select methods of data logging and data reduction that are compatible with the above and with each other
  6. Continually check the relevance of partial results to the critical uncertainties and alter the procedure as necessary


[Jon92]. J.C. Jones. 1992. Design methods. John Wiley & Sons, New York.
design/exploratory_methods.txt · Last modified: 2020.03.12 13:30 (external edit)