Correlations Flashcards
Correlation
Illustrates the strength and direction of an association between two co-variables
Scattergram
One co-variable is on the x-axis, the other on the y-axis.
Positive correlation
Co-variables increase together.
Negative correlation
One co-variable increases, the other decreases
Zero correlation
No relationship between variables.
Difference between correlations and experiments
In an experiment the researcher manipulates the IV and records the effect on the DV. In a correlation there is no manipulation of variables and so cause and effect cannot be demonstrated.
What is one strength of correlations?
Useful starting point for research.
By assessing the strength and direction of a relationship, correlations provide a measure of how two variables are related.
If variables are strongly related it may suggest hypothesis for future research.
What is a second strength of correlations?
Relatively economical.
Unlike a lab study, there is no need for a controlled environment and can use secondary data (e.g. government statistics).
So correlations are less time-consuming than experiments.
What is one limitation of correlations?
No cause and effect.
Correlations are often presented as casual e.g. by the media, when they only show how two variables are related.
This leads to false conclusions about causes of behaviour.
What is a second limitation of correlations?
Interviewing variables.
Another untested variable may explain relationship between co-variable.
This may also lead to false conclusions.