Correlation

Question 1

Define correlation.

Answer 1

• Correlation shows that there is a relationship or association between two variables
• Correlation never means causation - there is never a variable that causes another- a non-experimental method

Question 2

What is the difference between correlation and experiments?

Answer 2

Experiments
- Manipulate the IV to act on cause a DV
- Show cause and effect

Correlation
- Only shows a relationship between two variables not a cause
- Shows the strength & direction of the relationship it is not as strong in terms of supporting evidence for a theory

Question 3

What is a positive and negative correlation?

Answer 3

Positive correlation
- When two variables move in the same direction

Negative correlation
- When two variables move in the opposite or inverse direction

Question 4

What is a co-variable?

Answer 4

• The two variables you are looking at.

Question 5

What is a correlation coefficient?

Answer 5

• A number between -1 and +1 that shows the strength of the relationship between two variables
• The closer to 1 the correlation coefficient is, the stronger the relationship

Question 6

What are the three types of studies carried out in psychology that involve correlation?

Answer 6

• Twin studies
• Family studies
• Adoption studies

Question 7

How do you have to write in a hypothesis for correlational studies?

Answer 7

Non directional: ‘There will be a relationship’ between variable X and variable Y

Directional:’ As variable X increases/decreases so will variable Y’

Null hypothesis: ‘There will be no relationship between variable X and variable Y’

For correlational studies you must write relationship instead of difference - you will be able to work out whether it is correlational by the study saying what the relationship between two variables is

Question 8

Give one strength of correlational analysis.

Answer 8

• It allows researchers to investigate behaviours where it is not ethical to conduct an experiment
• e.g. the relationship between smoking cigarettes and developing cancer

Question 9

Give one weakness of correlational analysis.

Answer 9

• It can’t show that a variable causes an effect in another variable, only a relationship between the two.
• This means that conclusions from correlational analysis are not as strong as conclusions from experimental data which can show cause and effect

Question 10

Give another strength of correlational analysis.

Answer 10

• Correlations are very useful as a preliminary research technique, allowing researchers to identify a link that can be further investigated through more controlled research