Regression Lines

Question 1

4 assumptions made when doing a linear regression:

Answer 1

• normal sampling distribution
• interval data
• constant variance
• linear model

Question 2

A regression line produces…

Answer 2

A line of best fit that looks to minimise the sum of all the errors in the data

Question 3

Talk about inferential statistics

Answer 3

Inferences can be made from the sample size about the wider population

Used when you have sample statistics for hypothesis testing

Require random sample drawn from population

Question 4

What does the p value need to be below for it to be significant and why?

Answer 4

0.05

Means there is less than 5 percent chance the data is random and there is a 95 per cent chance it is due to the independent variable

Question 5

What does R-squared value tell you?

Answer 5

The % this model explains the outcomes by

Question 6

What needs to happen to the F-statistic for the test to be valid?

Answer 6

It’s p value needs to be less than 0.05

Question 7

Talk briefly about multiple regressions versus linear regressions…

Answer 7

Multiple regressions only show a relationship, not causality