BioStatistics/ Problem 1

Problem 1

1. present a contingency table

    

2. state the appropriate null and the alternative hypothesis

    

3. for each test

    

   1. determine a critical value using

       

   2. present a test statistic

       

   3. present a p-value

       

   4. interpret  the p-value

       

   5. state your decision

       

   6. state your conclusion

       

       

      In a study of risk factors for allergic disease among 13 and 14 year old school children, one risk factor was a family history of eating an unbalanced diet. In the study, 656 of 2107 children who had an unbalanced diet exhibited symptoms of rhinitis, whereas 677 of 2339 children who had a balanced diet exhibited symptoms of rhinitis. 

1. Perform the Z test to determine if there is a significant difference in the proportion of children with symptoms of rhinitis between those on an unbalanced diet and those on a balanced diet. 
2. Perform the chi-square test to determine if there is a significant difference in the proportion of children with symptoms of rhinitis between those on an unbalanced diet and those on a balanced diet.
3. Demonstrate the equivalence of the tests in a. and b.
4. Use a 95 % confidence interval to estimate the difference in the proportion of children with symptoms of rhinitis between those on an unbalanced diet and those on a balanced diet.
5. Provide an interpretation of your interval.
6. Demonstrate how the confidence interval can also be used to test the hypothesis.