Statistical Tests

Question 1

What is the purpose of statistical tests?

Answer 1

To determine whether difference or correlation in data is significant or due to chance

Question 2

Types of statistical tests

Answer 2

Chi squared
Student’s t-test
Spearman’s rank

Question 3

When is chi squared used?

Answer 3

To compare observed and expected data

Question 4

When is student’s t-test used?

Answer 4

To compare means

Question 5

When is spearman’s rank usedV

Answer 5

Correlation coefficient
- to identify and test the strength of a relationship between to sets of data

Question 6

What do the statistical tests produce?

Answer 6

Each test produces a number (calculated value)

Question 7

How do you use the number produced by statistical tests?

Answer 7

Use a probability table
Critical table: 0.05
- 5% likely to chance
- 95% likely to chance

Question 8

What if p ≤ 0.05 in a statistical test?

Answer 8

Difference is significant
0.05 or less probability that the data is due to chance
Reject null hypothesis

Question 9

What if p ≥ 0.05 in a statistical test?

Answer 9

Difference isn’t significant
Probs of it being due to chance is > 0.05
Accept null hypothesis

Question 10

What is a null hypothesis?

Answer 10

A hypothesis in which there is no statistical relationship between a set of observations (observed variables)