Correlation and regression

Question 1

What methods can be used to determine whether variables measured in different groups are related

Answer 1

• correlation
• regression

Question 2

Define correlation

Answer 2

describes the strength and direction of the relationship between 2 continuous variables

Question 3

What is correlation measured by

Answer 3

the correlation coefficient (a single number - quantitative measurement)

Question 4

What numbers define a perfect positive relationship and perfect negative relationship

Answer 4

• positive = 1
• negative = -1

Question 5

In hypothesis testing correlation coefficients describes what

Answer 5

the linear relationship between 2 continuous variables

H₀ - no linear relationship

H₁ - linear relationship

Question 6

What is regression

Answer 6

a model that uses one variable as a predictor x and the other as a response y

it finds an equation that best describes the relationship between the 2 variables

Question 7

What is a key difference between correlation and regression

Answer 7

correlation doesn’t allow prediction of one variable form the other

Regression allows one variable to be predicted from the other

Question 8

What is the linear regression equation

Answer 8

y = a + bx