4. Correlation

Question 1

What is bivariate data?

Answer 1

Data which has pairs of values for two variables

Question 2

Which variable goes on the x axis?

Answer 2

The independent variable or the explanatory variable

Question 3

Which variable goes on the y axis?

Answer 3

The dependent variable or the response variable

Question 4

What is correlation?

Answer 4

It describes the nature of the linear relationship between two variables.

Question 5

A regression line of y on x is written:

Answer 5

In the form y = a + bx

Question 6

What does the coefficient of b in y = a + bx tell you about?

Answer 6

The change in y for each unit change in x
- if data is positively correlated, b is positive
- if data is negatively correlated, b is negative

Question 7

What should you only use the regression line for?

Answer 7

Only use it to make predictions for values of the dependent variable (y axis) that are within the range of given data/