Research Methods : Correlations Flashcards
What’s a correlational study?
They investigate whether there’s a relationship/ association between two variables (co-variables)
Correlational study ads
• used when it’s impractical/ unethical to manipulate variables
• quick + easy as can use secondary data
• no manipulation of behaviour (high ecological validity)
• useful as preliminary research
Correlation study disads
• correlation doesnt equal causation
• no cause and effect relationships can be made
• may be a third intervening variable
• can’t establish which direction the relationship is
How do they differ from experimental methods?
With experiments, researcher controls/ manipulates IV to measure effect on DV so can be established. With correlation research, there’s no manipulation of one variable so causality can’t be established.
How do you write hypotheses for correlational research?
You state whether there is going to be a relationship or association between x and y
Types of correlation hypothesis
Null = no correlation
Non-directional = there will be a relationship ship/ association
Directional = state whether its positive or negative
How can researcher collect the data for co-variables?
Secondary data = from another source
Observational data = from experiment
Questionnaires = from questionnaires and interviews
Brain scanning technology = from brain technology to see activation of specific areas of the brain
What type of graph is used to plot the data?
Scatter graphs. The scatter dots indicate the degree of correlation between co-variables - this is a correlation co-efficient/ Pearson’s r
What’s a positive correlation?
As one co-variable increases or decreases, so does the other
(1.0 = perfect positive, 0.8 = strong positive, 0.3 = weak positive)
What’s a negative correlation?
As one co-variable increases, the other decreases
(-0.3 = weak negative, -0.8 = strong negative, -1.0 perfect negative)
What’s a zero correlation?
There is no relationship between variables
What’s a curvilinear relationship?
As one variable increases, so does the other but only up to a certain point, then as one variable continues to increase, the other decreases