Chapter 4 - Correlation

Question 1

What is Bivariate Data?

Answer 1

Data which has pairs of values for two variables

Question 2

What is Correlation?

Answer 2

Correlation describes the nature of the linear relationship between 2 variables

Question 3

What does it mean to have a casual relationship?

Answer 3

If one variable causes change in the other,

e.g., An increase in House Prices and and increase in Homeless People could have a Casual Relationship

Question 4

What is the Regression Line?

Answer 4

It is the line of Best Fit, it is in the form:

y = a + bx

The coefficient b tells you the change in y for each unit change in x.

• if data is positively correlated, b will be positive
• if data is negatively correlated, b will be negative

this is because b is the gradient of the regression line.

Question 5

When should you use the regression line?

Answer 5

You should only use the regression line to make predictions for values of the dependent variable that are within the range of the given data.