Use a significance level of $0.05$ for all tests below.

Research the percentages of each blood type that the Red Cross states are in the population. Now use your class as a sample. For each student note the blood type. Is the distribution of blood types in your class as expected based on the Red Cross percentages?

Solution

VerifiedPerform the chi-square goodness-of-fit test.

Determine the observed frequencies $O$.

The expected frequencies $E$ are the product of the sample size $n=40$ and the probabilities $\dfrac{1}{c}$ (with $c$ the number of categories).

The chi-square subtotals are the squared differences between the observed and expected frequencies, divided by the expected frequency.

$\chi^2_{sub}=\dfrac{(O-E)^2}{E}$

The value of the test-statistic is then the sum of the chi-square subtotals:

$\chi^2=\sum \dfrac{(O-E)^2}{E}$

Determine the critical value using table G with $df=c-1$ and $\alpha=0.05$.

If the test statistic $\chi^2$ is more than the critical value, then reject the null hypothesis.

## Create an account to view solutions

## Create an account to view solutions

## Recommended textbook solutions

#### Elementary Statistics: A Step by Step Approach

10th Edition•ISBN: 9780076793907 (5 more)Allan G. Bluman#### Probability and Statistics for Engineers and Scientists

9th Edition•ISBN: 9780321629111 (9 more)Keying E. Ye, Raymond H. Myers, Ronald E. Walpole, Sharon L. Myers#### The Practice of Statistics for the AP Exam

5th Edition•ISBN: 9781464108730Daniel S. Yates, Daren S. Starnes, David Moore, Josh Tabor#### Statistics and Probability with Applications

3rd Edition•ISBN: 9781464122163Daren S. Starnes, Josh Tabor## More related questions

1/4

1/7