Psychology - Research Methods - Correlations, probability and statistics

Question 1

Co-variables

Answer 1

The variables investigated in a correlation

Question 2

Correlations

Answer 2

A technique for analysing the strength of the relationship between two co-variables

Question 3

Where is the data for a correlation obtained?

Answer 3

from a non experimental source like a survey

Question 4

What will a correlation analysis show?

Answer 4

A positive correlation, negative correlation and no correlation

Question 5

Correlation coefficient

Answer 5

the strength of a correlation

Question 6

What are the advantages of a correlation?

Answer 6

• Allows psychologists to establish the strength of the relationship between two variables and measure it precisely
• allows researchers to investigate things that cannot be manipulated
• predictions can be made

Question 7

What are the disadvantages of correlations?

Answer 7

• Correlational analysis cannot demonstrate cause and effect
• there may be a third variable - only measures linear relationships

Question 8

Level of statistical significance

Answer 8

The level at which the decision is made to reject the null hypothesis in favour of the experimental hypothesis, states how sure we are that the IV is effecting the DV and that it’s not chance.

Question 9

What is the standard level of significance?

Answer 9

p<0.05 or 5%

Question 10

Why is the 5% level of significance used in psychological research?

Answer 10

• not too strict or lenient
• minimises chances of type 1 or type 2 errors

Question 11

When are 5% significance levels usually used?

Answer 11

When there is a directional one tailed hypothesis that has been clearly stated in the research