Methodology and ExplanationXX50125

Lecture 3: Interviews and questionnaires

Dr. Danaë Stanton Fraser

Methodology and Explanation 2005

Lectures

1. Introduction to Methods

2. Experiments

3. Interviews and questionnaires

4. Usability testing

5. Ethnography

Methodology and Explanation 2005

Why Interview?

• Good for obtaining information about– Opinions– Feelings– Goals (organisational, personal and system)– Things you didn’t know you needed to know

• Bad for gathering (large volumes of) data

Methodology and Explanation 2005

Interview Preparation

• Decide objectives• Read background material• Decide whom to interview• Set up the interview• Decide interview structure• Write down questions you will ask and pointers for

questions you might ask

Methodology and Explanation 2005

Open Questions

E.g. “How do you find using this technology in your lectures?”

• Little control• Hard to analyse • Hard to keep focussed on interview objectives• May unsettle interviewee• Time consuming and can be difficult to analyse

However:• May gain more depth, rich data• May tell you things you had not considered• May give you ideas for future projects

Methodology and Explanation 2005

Closed Questions

E.g. “How many courses do you teach?” “How many times have you used this technology?”• May settle interviewee• Easy to analyse• Easy to maintain focus• Observation and use of data may be more efficient

However:• Data may not be as rich

Methodology and Explanation 2005

Question Pitfalls

• Leading questions– “How bad is the current system?”

• Double questions/poor structure– “How often does the system fail, and how do you

fix it when it does?”

• Stay focussed. If you are unlikely to be able to make use of the answer don’t ask the question!

Methodology and Explanation 2005

Question Structure

• Pyramid

– Start with closed questions, finish with open

– Good for settling nervous interviewees as answers are ‘easy’ early on

• Funnel

– Start with open questions, finish with closed

– Good for aggressive interviewees as opinions are asked for early on• Diamond

– Closed -> Open -> Closed, Good all-round technique• Structured/unstructured

– All interviews may vary depending on how focused you intend to be on the prepared structure

Methodology and Explanation 2005

Starting the Interview

• Dress• Greeting – first time

– Who you are – Why you want to interview them– What objectives you want to achieve from the interview– That the information they give is confidential and how it

might be used• Subsequent greetings should discuss an issue from or

summarise the previous interview• Don’t just “be yourself”

Methodology and Explanation 2005

During the Interview

• Introduce each line of questioning

• Probing

– E.g. “Why?”

– Shows that you are listening

– Good for keeping interview focus

– Double-check information and notes• Taking notes

– Not too many

– Maintain eye contact

– Go back over important points• Use of sound recorders

Methodology and Explanation 2005

Focus Groups

• Normally 3-10 people

• A representative sample of typical users

• Enables people to put forward ideas in a supportive environment

• Facilitator guides and prompts

• Discussion recorded

• Low-cost but need good facilitator

Methodology and Explanation 2005

Questionnaires

• For wider coverage

• Need to know the right questions (through interviews and background)

• Focus on objectives

• Don’t ask unnecessary questions

• Keep it short and facilitate response

• Open and Closed questions

• Scaling

Methodology and Explanation 2005

Likert Scale

• Short statements about the features to be evaluated

• Divide the items into groups with same number of positive and negative statements in each group

• Decide on scale – even or odd, number of points

strongly agree

agree neutral disagree strongly disagree

Methodology and Explanation 2005

Questionnaire difficulties

• The ‘halo effect’– Respondent answers everything the same by not

differentiating between questions– Mix questions up on different subjects

• Leniency– Some respondents rate everything too well– Move the ‘average’ category left (or right) of centre and

make scale descriptors stronger• Central tendency

– Respondents rate everything as average– Increase the number of points on the scale and adjust the

scale descriptors to cover a smaller range of opinions

Methodology and Explanation 2005

Also…evaluation during active use

• System refinement as a result of experience or in response to changes in users

– interviews and focus group discussions

– continuous user-performance data logging

• look at both frequent and infrequent error messages

• analyse sequences of actions to suggest improvements or new actions

• BUT respect people’s rights and consult them first!

– User feedback mechanisms

• on-line forms, email and bulletin boards

• workshops and conferences