Lesson 4: Correlations

Question 1

What is a correlation?

Answer 1

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

Question 2

What is a positive correlation?

Answer 2

As one variable increases, so does the other

Question 3

What is a negative correlation?

Answer 3

As one variable increases, the other one decreases

Question 4

What does it mean to have no correlation?

Answer 4

There is no relationship between the two variables

Question 5

What are the different strengths of correlations?

Answer 5

• Strong positive correlation will be closer to +1
• 0 means no correlation
• Strong negative correlation will be closer to -1

Question 6

Advantages of correlations

Answer 6

1. Establish strength of the relationship with precise measures
2. Can investigate things that could not be studied e.g because of ethical reasons, natural occurrences
3. Predictions can be made

Question 7

Disadvantages of correlations

Answer 7

1. No cause and effect, EV not taken into account

2. Only measure linear relationships, and not curvilinear relationships