Requirements Elicitation Techniques: Interviews and Repertory Grid

1
Requirements Elicitation Techniques Interviews
and Repertory Grid

• RE-2007
• Aleksi Vuorenmaa

2
Conversational Methods

• Conversation is one of the most prevalent forms
  of social interaction
• Natural way to express need and ideas, ask and
  answer questions
• People are usually happy to describe their work
  and difficulties they face
• Interview is the most typical conversational
  requirements elicitation method

3
Interview Description

• Interviews
• Conducted by an experienced analyst with generic
  knowledge about the application domain
• Analyst discusses the desired product with
  different groups of people and builds up an
  understanding of their requirements
• Requirements are articulated by stakeholders and
  communicated with the analyst

4
Interviews

• Very commonly used in requirements development
• Provide rich collection of information
• - Labor intensive
• Meeting setup, transcript producing and analyzing
  from records of live interaction takes time
• - Large amount of qualitative data
• Hard to analyze

5
Interviews

• Divided into two categories
• structured interviews
• Pre-defined agenda and questions
• Systematic flexible
• - Time consuming, information missing
• open-ended interviews
• No pre-defined agenda
• Quick, simple and flexible
• - Provides no complete well-structured knowledge

6
Repertory Grid
7
Repertory Grid

• Interviewing technique which uses factor analysis
• Convenient way of understanding other people in
  their own terms
• Basis in psychology
• Devised by George Kelly around 1955
• Based on his Personal Constructs theory of
  personality
• Used by psychiatrist

8
Repertory Grid

• A.k.a construction matrix
• Helps to classify domain data into elements and
  constructs
• Through the use of statistical grouping process,
  elements are distinguished by their
  characteristics, represented as constructs
• Personal constructs are bipolar dimensions which
  group the elements into varying clusters
  according to their similarities and differences
• Elements may be people, things, events or
  experiences related to the problem or purpose

9
Pros and Cons

• Can help to distill the similarities and
  differences within their domain
• Can lead to surprising relations that were not
  known to the domain expert
• - Dependent upon the quality and accuracy of the
  constructs used
• - Risk of incorrectly assuming causality between
  elements
• Interpretation of the data is more important than
  gathering it

10
In practice

• A short demo of a web tool for repertory grid
  interview
• scivesco.web
• interview
• results

11
References

• Zheying Zhang (2007) Effective requirements
  development - a comparison of requirements
  elicitation methods. INSPIRE2007.
• Wikipedia (5.11.2007) Repository Grid
  http//en.wikipedia.org/wiki/Repertory_grid
• Guy Davis, University of Calgary Requirements
  Gathering Techniques http//www.guydavis.ca/seng/
  seng611/techniques/
• scivesco.web (5.11.2007) http//www.eac-leipzig
  .de/scivescoweb/