1. Make up an example of a study using the data below to test for an association between the 4 groups (make up what these 4 groups represent in your example) and the 3 responses (make up what these 3 responses represent). You cannot use an example that was used in the class. For example, you cannot use the example of the amount of exercise (responses) by location of student residences (groups) where we tested whether where students live is associated with how much exercise they report to get. Include the population that you use (if about people), hypothesis statements, identify the type of test, and include a few sentences about your results. No more than 1/3 a page for your write up for this problem.
|
response1
|
response2
|
response3
|
|
group1
|
20
|
24
|
80
|
|
group2
|
22
|
38
|
104
|
|
group3
|
13
|
28
|
81
|
|
group4
|
7
|
18
|
54
|
2. Using the data provided below, analyze and write a scenario that reports a confidence interval for the difference in proportions using columns A and B. Be sure to write what the 2 populations are, what the values (the 0 and the 1) represent, and a sentence that gives an interpretation of the confidence interval. Make sure you include some summary statistics. Again, you cannot use an example that was used in class. Be creative! No more than 1/3 of a page for your write up here.
Data for confidence interval.
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A
|
B
|
|
0
|
0
|
|
0
|
1
|
|
0
|
0
|
|
0
|
1
|
|
1
|
0
|
|
0
|
0
|
|
0
|
0
|
|
1
|
0
|
|
1
|
1
|
|
1
|
0
|
|
1
|
0
|
|
1
|
1
|
|
0
|
1
|
|
1
|
0
|
|
0
|
0
|
|
0
|
0
|
|
0
|
1
|
|
0
|
0
|
|
0
|
0
|
|
1
|
0
|
|
0
|
0
|
|
0
|
0
|
|
0
|
0
|
|
0
|
0
|
|
0
|
0
|
|
0
|
1
|
3. Using the data provided in the Excel file in course documents for Midterm, test for a difference in mean number of medical conditions in patients who were categorized into 4 groups based on the number of months since enrollment into the study before tooth loss: 1-24 months, 25-36 months, 37-48 months, and more than 48 months. Give the null and alternative hypothesis in notation, include summary statistics or a table, and write a few sentences about the results. This question is based on a study reported by
Xi Chen, BMed, PhD; Jennifer J.J. Clark, BS; SupawadeeNaorungroj, DDS, MS
Length of tooth survival in older adults with complex medical, functional and dental backgrounds
JADA 2012;143(6):566-578
Again, no more than about 1/3 of a page for your answer.
4. Using the data in question 3 and the results in the template that you used,
a. Why is the margin of error that is reported in the template for the 25-36 month category the largest of the 4 groups?
b. If you wanted the 95% confidence interval for the mean number of medical conditions for that group to be no wider than 3 medical conditions, and you use a standard deviation of 4.0, how many people do you need to participate in the study who would be classified into this 25-36 month category?
Attachment:- Data.rar