Stats 1: Hypothesis testing

Question 1

What is the null hypothesis, H₀ ?

Answer 1

• the hypothesis that you assume to be correct

Question 2

What is the alternative hypothesis, H₁ ?

Answer 2

• tells you the parameter if you assumption is shown to be wrong

Question 3

What are one-tailed tests?

Answer 3

• hypothesis tests with alternative hypotheses in the form H₁: p<… and H₁: p>….

Question 4

What are two-tailed tests?

Answer 4

• hypothesis test with an alternative hypothesis in the form H₁ : p does not equal to ….

Question 5

What is a critical region?

Answer 5

• a region of the probability distribution, which, if the test statistic falls within it, would cause you to reject the null hypothesis
• there are two critical regions for a two-tailed test

Question 6

What is the critical value?

Answer 6

• the first value to fall inside the critical region

Question 7

What is the actual significance level?

Answer 7

• the probability of incorrectly rejecting the null hypothesis

Question 8

How do you carry out a one-tailed hypothesis test?

Answer 8

• formulate a model for the test statistic
• identify suitable null and alternative hypotheses
• calculate the probability of the test statistic taking the observed value, assuming the null hypothesis is true
• compare this to the significant level
• write a conclusion in context of the question

Question 9

For which test do you need to halve the significance level at the testing end?

Answer 9

• for two-tailed tests