Research Methods B Flashcards
What is an experiment?
- Manipulation of one or more variables
- Determine the effect of this manipulation on another variable
- To test the cause-effect relationship between variables (test of causality)
What are hypotheses?
- A hypothesis is a testable prediction
- Hypotheses are derived from theories
- Science is about testing hypotheses
What is an experimental/alternative hypothesis, and give an example?
- Treatment DOES leads to an effect
- ‘Learning with background music DOES lead to lower marks’
What is a null hypothesis, and give an example?
- Treatment does NOT lead to an effect
- ‘Learning with background music does NOT lead to lower marks’
Explain dependent and independent variables
- Manipulating the independent variable changes the value of the dependent variable
- Independent is changed, dependent is measured
What is a nuisance variable, and give an example?
- An additional factor that affects the dependent variable
- Background music (independent variable) affecting mark (dependent variable)
- Place/time of testing (nuisance variables) affecting mark (dependent variable)
Explain the difference between an experimental group and a control group, and give examples?
Experimental group:
- Group receiving the important level of the independent variable
- e.g. students listening to music as they study
Control group:
- Group that serves as the untreated comparison groups
- Group receives comparison level of the independent variable
- e.g. students not listening to music as they study
What are parametric tests?
- Are based on assumptions about the distribution of measures in the population; a normal distribution is usually assumed
- If comparing more than one group, the groups should have equal variance (homogeneity of variance, e.g. are the variances similar)
- Parametric tests are powerful but can be used (e.g. when data doesn’t meet the underlying assumptions of tests)
What are non-parametric tests?
- They don’t make assumptions about population distributions/distribution free tests
- Lower in power and less flexible than parametric tests
Should parametric tests be used whenever possible?
- Yes!
- More are quite robust and limitations well documented
- Possibly use transformations (e.g. logs) to normalise data distributions
How do you test for parametric assumptions, and why?
- Kolmogorov-Smirnov test
- The determines the likelihood of the data belonging to a normal distribution (given as a p value)
To test for homogeneity of variance:
- Levene’s test
- This determines the data sets are from the same population
Explain homogeneity of variance
- If the data isn’t significantly different from a normal distribution and there is no significant difference between the variances of the samples - there is homogeneity of variance
- Therefore, we can go ahead and perform a parametric test
If there isn’t homogeneity of variance, we need to perform the equivalent non-parametric test
Explain parametric and non-parametric test in terms of testing for significant differences
- Both types of tests are available to test for significant differences between data sets
- Parametric tests make assumptions about population parametric (e.g. are distribution dependent)
- Parametric tests require interval or ration scale data
- Violation of test assumptions lead to erroneous interpretations of the data
- Non-parametric tests can be used as alternative to parametric tests
- Non-parametric tests make no assumptions about population
- Non-parametric tests can use data at nominal level
- Non-parametric tests aren’t as powerful as parametric statistical tests (can fail to detect differences)
Explain the Chi-Square Test for goodness of fit (X2)
- Used on unrelated data (every participant/case yields data for only one category)
- Used to answer questions about the proportions of a population distribution (e.g. gender bias in the psychology department)
- Used to compare different levels of ONE variable
- Compared the same proportions to population proportions as specified by the null hypothesis
What are observed frequencies?
- The observed frequencies are the number of participants measured in individual categories
- These frequencies are then compared to frequencies predicted by the null hypothesis (the expected frequencies)
Explain working out expected frequencies
- The exact form of these frequencies changes according to what the null hypothesis is
No difference between the specified categories (e.g. the number of men and women is equal)
No difference between the frequency distribution for the observed categories and existing population (e.g. the number of men and women in the computing department reflects the gender balance in the whole university)
Explain interviews
Aim to find out as much as possible about the participants’ experiences and meanings
Explain structured interviews
Often used when a questionnaire is being administered verbally, and may not be useful in exploring the experiences of the participant as fully as using other methods
Explain semi-structured interviews
Allows flexibility on both the participant and researcher
Explain loosely structured interviews
- Loosely structured schedules usually have fewer specific questions and topics
- Can be more useful in focus groups or when other activities are used
Explain unstructured interviews
Unstructured interview schedule is often considered to be a misnomer - how ‘unstructured’ can you be on paper and in your intentions?
What are focus groups?
- Aim to find out as much as possible abut the participants’ understandings and meanings, with more than one participant
- Individuals come together to discuss a topic
- Involves sharing of experiences, ideas, views, etc.
Why do we use focus groups?
- Contextualises collective understandings and sense-making
- Useful in considering peoples’ shared understandings
- Sensitive to points of consensus and disparity
Explain face to face focus groups
- Effort from the researcher: you must act as a facilitator to your participants
- Ensure the topic is followed
- Focus group schedule used - interview schedule, list of questions, topics and prompts for discussion
- Lead discussion - but more them than you
- Needs attention to interaction in ‘the room’
- Acknowledge agreements and disagreements
- Ensure people are respected and heard
Explain online focus groups
- The format may be different, but the content seems relatively stable between face to face and online focus groups
Asynchronous Online Focus Groups
+ More time to think about responses
- Could be technological issues associated with them
Synchronous Focus Groups
+ Technology can provide different types of environments for participants to engage with
- Requires a good and consistent bandwidth, and reliant on individual schedules
Groups in the “virtual world”
+ Avatars may lead to greater engagement and co-creation activities
- Assumes a certain level of skill/ability is needed
What are ‘alternative’ qualitative data collection methods?
- Interviews and focus groups are largely seen as the key type of qualitative data collection
- There are several other ways of gaining insight into people’s experiences, sense-and-meaning-making practices, and perceptions/constructions/views