Correlations

Question 1

What is a correlation?

Answer 1

A correlation is a technique for analysing the strength of the relationship between two quanitative variables = co-variable

Question 2

What are the three types of correlation?

Answer 2

• positive correlation (as one variable increases, the other increases as well)
• negative correlation (as one variable increases, the other decreases)
• no correlation (no relationship between the two variables)

Question 3

Describe the strength of correlations

Answer 3

Strength between = -1 to +1:

• strong positive correlation coefficient = no. closer to +1
• no correlation = 0 (close to 0)
• strong negative correlation coefficient = no. closer to -1

Question 4

What is the correlation coefficient?

Answer 4

The strength of the correlation = correlation coefficient

Question 5

Where are correlations plotted?

Answer 5

Scatter graph

One variavle forms x-axis + other variable forms y-axis

Question 6

What are rhe ads of correlations?

Answer 6

• allow psychs to establish the strength of the relationship between two variables + measure it precisely
• allow researchers to investigate things that could not be manipulated experimentally for ethical or practical reasons
• once a correlation has been conducted, predictions can be made about one of the variables based on what is known about the other variable e.g. we find that high stress causes high cholesterol so we know now that low stress = low cholesterol

Question 7

What are the disads of correlation?

Answer 7

• correlational analysis cannot demonstrate cause + effect = can’t tell which variable influences the other
• there may be the case of a third unknown variable, even if there is a correlation between two variables, that are not related
• correlations can only measure linear relationships + doesn’t detect curvilinear relationships = positive relationship till a point and then negative (or vice versa)