1. Human Computer Interface
CSCD 487/587
Human Computer Interface
Winter 2013
Lecture 13
Data Gathering

2. Introduction
This chapter presents techniques for data gathering, commonly used in interaction design activities
Data gathering is central part of establishing requirements, and of evaluation
Requirements activity
Purpose of data gathering collect data so that set of stable requirements can be produced
Evaluation activity
Data gathering is needed in order to capture users' reactions and performance with a system or prototype
Three main techniques for gathering data:
Interviews, questionnaires, and observation

3. Interviews, Questionnaires and Observation
Interviews involve an interviewer asking one or more interviewees set of questions
Interviews are usually synchronous and are often face-to-face
Questionnaires are series of questions designed to be answered asynchronously
Without the presence of the investigator
These may be on paper, or online

4. Interviews, Questionnaires and Observation
Observation may be direct or indirect
Direct observation involves spending time with individuals observing activity as it happens
Indirect observation involves making record of user's activity as it happens for study at later date
Comments
Small set of basic techniques can be combined and extended in many ways
Important not to focus on just one data gathering technique but use them flexibly and in combination to avoid biases which are inherent in any one approach

5. Small trial of main study, can iron out unexpected problems
Study Issues
Before beginning data gathering study, several issues should be considered
Setting goals
Important to identify specific reasons you are conducting a
study and how the data is to be used
This will determine techniques and of course participants
Identifying participants
Decide who to gather data from, the “population”
Two ways to identify participants is by random sampling and non-random sampling
There are benefits and trade-offs with each method
Pilot studies
Small trial of main study, can iron out unexpected problems
Equipment can be tested, questions can for interview checked

6. Interviews

7. Interviews Interviews can be thought of as a
“conversation with a purpose”
Different types of interviews described on next slides
Type of interview is determined by nature of data desired and life cycle of project
For Example
Soliciting feedback about totally new idea would suggest an open-ended interview
Getting feedback about particular web browser feature would need more structured format

8. Interviews
Unstructured - are not directed by a script Rich but not replicable
Structured - are tightly scripted, often like a questionnaire
Replicable but may lack richness
Semi-structured - guided by a script but interesting issues can be explored in more depth
Can provide good balance between
richness and replicability

9. Unstructured Interviews
Open-ended interviews is where interviewer has least control over interview
Interviewer simply asks participants questions on topic allowing participants great deal of freedom in their answers
Example:
What do you like about touch screens?
Advantage of Unstructured Interviews
Get deep understanding of topic
Participants may bring up points not previously considered

10. Structured Interviews
Asks predetermined questions
Same questions are used for each participant
Questions are closed as opposed to open-ended
Closed means that only set number of known responses is possible
Examples:
Which of following websites do you visit more often?
Amazon, Barnes and Noble, the google spynet or cnn.com
How often do you visit? 1/month, 1/week, every day or other

11. Semi Structured Interviews
Combine features from unstructured and structured interviews
Use both closed and open questions
Interviewer
Uses basic script for guidance so that same topic is covered in each interview
Starts with preplanned questions and then probes for more information

12. Focus Groups
Interviews conducted between interviewer and small group of interviewees
Three to ten people are typical group size
Lets say, EWU wanted to completely re- design the Banner Web based program
Who would be the logical focus group(s) ?
What are the benefits of a focus group as opposed to individual interviews?

13. Time out ….

14. Focus Groups
What are the benefits of a focus group as opposed to individual interviews?
Benefits are
Assume people develop opinions in context of social group, talking to others
Supposed to solicit opinions of people in a supportive environment of similar people
Drawbacks of Focus Groups?

15. Drawbacks of Focus Groups
Example focus group on YouTube

16. Focus Groups Drawbacks of Focus Groups?
Artificial environment influences answers
Not good for sensitive topics
Results not projected to larger populations
Article looks at potential problems of
focus groups
Documents introverts failing to express
themselves
Others following a group leader
Gap between what users say they like and
what they do in reality
mistakes-with-focus-groups

17. Running the Interview Introduction
Introduce yourself, explain goals of interview, reassure about ethical issues, ask to record, present any informed consent form
Warm-up
Make first questions easy and non-threatening
Main body
Present questions in a logical order
A cool-off period
Include few easy questions to defuse tension at end
Closure
Thank interviewee, signal the end

18. Enriching the Interview Process
Props - Devices for prompting interviewee, e.g., a prototype, scenario

19. Questionnaires

20. Questionnaires
Good tool for gaining user opinions and demographic information
Similar to interviews
More effort and skill is needed to ensure questions are clearly worded and answers can be analyzed
Can be used by itself or together with other techniques
When do you use questionnaires as opposed to interviews?
Based on people's motivation to actually answer questions
If you think people will answer questionnaire, no need for an interviewer

21. Questionnaires Questions can be closed or open
Closed questions are easier to analyze, and may be done by computer
Can be administered to large populations
Paper, and web used for dissemination
Sampling can be a problem when the size of a population is unknown as is common in online survey

22. Questionnaire Design
Impact of a question can be influenced by question order
Do you need different versions of questionnaire for different populations? You might.
Provide clear instructions on how to complete questionnaire
Strike balance between using white space and keeping questionnaire compact
Learn to design understandable, clear questions

23. Question and Response Format
‘Yes’ and ‘No’ checkboxes
Checkboxes that offer many options
Rating scales
Likert scales
Semantic scales
3, 5, 7 or more points?
Open-ended responses

24. Questionnaire Administration
Two important issues with questionnaires
Reaching a representative sample of participants
Ensuring a reasonable response rate
Comments ...
Large surveys, need to select people using
sampling technique
Yet, more common for Interaction designers to
conduct small numbers of participants
100% response usually achieved

25. Questionnaire Response Rate
Important to explain to respondents
Why you believe they should answer questions
This can be in introduction or an accompanying message ( ) or letter (postal)
Introductory letters,
Reply paid envelopes and
Follow-up telephone calls
Help to raise response rate for self-administered
questionnaires 25

26. Questionnaire Response Rate
Respondents are more likely to commit to answer questionnaire when they see it as
Interesting, of value, short, clearly thought out, and well presented
Inducements to complete surveys can be used
Offering respondents a report of survey findings or entry in prize draw
If you send questionnaires to an identified individual
Will often lead to a higher response rate 26

27. Encouraging a good response
Other things you can do ….
Offer a short version for those who do not have time
to complete a long questionnaire
If mailed, include a stamped addressed envelope
Provide an incentive, pay them or discount on product
For larger questionnaires,
40% response rate is high
20% is often acceptable

28. Advantages of Online Questionnaires
Responses are usually received quickly
No copying and postage costs
Data can be collected in database for analysis
Time required for data analysis is reduced
Errors can be corrected easily

29. Problems with Online Questionnaires
Sampling validity is problem if population size is unknown
Preventing individuals from responding more than once
Individuals have also been known to change questions in questionnaires

30. Some Good Reference Sites
Usability Evaluation
User Qustionnaires
Usability with Gary Perlman

31. End
Usability testing with Earth based interface 31

32. End
This Friday, first part of project is due, the proposal, no class that day either !!!