Hypothesis Testing

Question 1

What is the purpose of performing a statistical hypothesis test?

Answer 1

To either make assertions about the distribution of data or to determine if one set of results differs from another.

Question 2

What is a null hypothesis?

Answer 2

A null hypothesis is a default assumption made in statistical hypothesis testing based on domain or problem knowledge.

Question 3

What is the significance level, often denoted as alpha?

Answer 3

The significance level, typically set at 0.05 or 5%, is the threshold used to determine if a result is statistically significant.

Question 4

What are one-tail and two-tail tests?

Answer 4

One-tail tests involve keywords like ‘more than’ or ‘less than’, while two-tail tests involve keywords like ‘equals.’

Question 5

What is a t-test used for?

Answer 5

A t-test is used to determine if two samples represent the same population or distribution.

Question 6

What are the two types of t-tests commonly used?

Answer 6

The two types of t-tests are independent sample t-test and paired (dependent sample) t-test.

Question 7

What does the p-value represent in a t-test?

Answer 7

The p-value represents the probability of obtaining the observed results under the assumption that the null hypothesis is true.

Question 8

What is the decision rule based on the p-value in a t-test?

Answer 8

If the p-value is greater than the significance level (alpha)

Question 9

Name the type of t-test
* Compare means of two groups
* Two blood pressure measurements on the
* Do students score higher, on average, then 80 if their test is at 8 AM?

Answer 9

1. Independent t-test
2. Dependent t-test
3. One sample t-test