# Quiz 2: Two-way Tables

Test your knowledge of the material on two-way tables in the following
quiz.

**What is the ***best* way to test the significance of
the association between two categorical variables in a two-way frequency
table?

- Using a chi-square test
- Using a t-test
- Using a one-way ANOVA
- Using a linear regression

**What is the best measure used to quantify the
***strength* of association between two categorical variables in a
two-way frequency table?

- Chi-square test
- Cramerâ€™s
*V*
- Pearsonâ€™s correlation coefficient
- Odds ratio
- None of the above

**What is the ***null hypothesis* for a chi-square test
of independence in a two-way frequency table?

- The two variables are independent
- The two variables are dependent
- The two variables are correlated
- The two variables are not correlated

**What is the ***alternative hypothesis* for a chi-square
test for independence in a two-way frequency table?

- The two variables are independent
- The two variables are dependent
- The two variables are uncorrelated
- None of the above

**What are the assumptions for the validity of a chi-square
test for independence in a two-way frequency table?**

- The observations are independent and randomly sampled
- The expected frequencies for each cell in the table are greater than
5
- The variable are categorical
- All of the above

**When interpreting the results of a chi-square test for
independence in a two-way frequency table, what does a ***p*-value
of less than 0.05 indicate?

- There is evidence of association between the two variables
- There is no evidence of association between the two variables
- The variables are correlated
- The variables are uncorrelated

**How do you interpret the ***p*-value in a chi-squared
test for independence in a two-way frequency table?

- A small
*p*-value indicates evidence against the null
hypothesis
- A large
*p*-value indicates evidence against the null
hypothesis
- A small
*p*-value indicates evidence in favor of the null
hypothesis
- A large
*p*-value indicates evidence in favor of the null
hypothesis.

**When both variables are ***ordered* in a two-way
frequency table, the most focused test for association is:

- The Pearson chi-squared test
- The Likelihood ratio chi-squared test
- The CMH test for general association
- The CMH test for non-zero correlation

## Answers

1: a; 2: b; 3: a; 4: b; 5: d; 6: a; 7: a; 8: d