Surveys ​
- one of the most commonly used research techniques.
- strength: large number of responses quickly.
- respondents can be geographically dispersed.
- can help capture the "big picture"
Survey Pros and Cons ​
Pros ​
- easy to collect data from a large number of people.
- do not require (advanced) tools for development.
- can be distributed easily.
Cons ​
- not very good at getting detailed data.
- can lead to biased data. (recall bias: subject to interpretation or memory)
- not possible to ask follow up questions.
population of interest
== target population
== targeted users
(in hci)
the population of interest is filtered based on inclusion criteria such as profession, etc...
Probabilistic Sampling ​
in a probability sample it is known exactly how likely it is to select a participant from the sample.
Stratification ​
- A stratified sample is when you divide your entire population in separate subpopulations, known as strata.
- A separate sample is drawn within each subpopulation.
- stratification can help to have subgroups of the same size.
Example:
- Survey of BIT students:
- Subpopulations: first-years, second-years, third-years
- Each year has different number of students, but stratified sample invites the same number from each year.
Non-probabilistic Sampling ​
- goal in HCI is not usually population estimates.
- usually population is not well defined.
Non probabilistic sampling examples:
volunteer opt-in panels.
self-selected surveys.
snowball recruiting. (respondents recruit other people)
ask about demographic data to confirm validity.
oversampling: asking a large amount of people relative to the estimated population size, to avoid biases.
Random sampling of usage:
- user is asked to fill a survey every 10th time they load a website.
Self selected survey:
- respondent finds the survey online.
- most natural data collection method.
Developing Survey Questions ​
- open ended questions.
- close ended questions
- scale (excellent - poor)
- yes or no questions.
Common problems ​
- two questions in the same question.
- use of negation
- biased wording
- hot button words
Overall Structure ​
- instructions
- nice layout
- not too long
Online vs Paper ​
different people will have different access to both. So depends on the audience.
Testing ​
- review by colleagues and analysts
- Interviews with potential respondents.
- pilot study of the survey tool and implementation procedures.
How to increase response rate: ​
- offer reward
- introductory letter
- ease of submitting
- multiple contacts with respondent
Data analysis ​
- quantitative and qualitative data is separated
- data is cleaned: removed invalid responses.
- if it is quantitative data use descriptive statistics
- if it is qualitative data use content analysis (chapter 11)