Suppose that we want to testing a new vaccine to see if it is effective. Randomly...

Suppose that we want to testing a new vaccine to see if it is effective. Randomly assigned patients are

In a sample, we find the following results:

	Test + for disease	Test - for disease	Total
Patient vaccinated	2	5	7
Patient not vaccinated	22	9	31
Total	24	14	38

a. Test they hypothesis that the two factors: vaccination status and test result are independent. If they are statistically dependent, we will have evidence that the vaccination is effective. Write the null and alternative hypothesis for this test.

b. Find the test statistic. Show your work.

c. Use the critical value of 6.635 for a 1% level of significance to state whether or not we should reject the null hypothesis.

d. Conclusion: Do we have statistically significant evidence that the vaccination status and test result do depend on each other at the 1% level of significance? Yes or No.

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Expert Solution

orchestra answered 1 year ago

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