In: Statistics and Probability
Use the sample data and confidence level given below to complete parts (a) through (d). A drug is used to help prevent blood clots in certain patients. In clinical trials, among 4778 patients treated with the drug, 104 developed the adverse reaction of nausea. Construct a 99% confidence interval for the proportion of adverse reactions.
a) Find the best point estimate of the population proportion p.
0.022 (Round to three decimal places as needed.)
b) Identify the value of the margin of error E.
E = __(Round to three decimal places as needed.)
Solution :
Given that,
n = 4778
x = 104
= x / n = 104 / 4778 = 0.022
a) Point estimate = 0.022
1 - = 1 - 0.022 = 0.978
At 99% confidence level the z is ,
= 1 - 99% = 1 - 0.99 = 0.01
/ 2 = 0.01 / 2 = 0.005
Z/2 = Z0.005 = 2.576
Margin of error = E = Z / 2 * (( * (1 - )) / n)
= 2.576 * (((0.022 * 0.978) / 4778)
b) Margin of error = 0.005
A 99% confidence interval for population proportion p is ,
- E < P < + E
0.022 - 0.005 < p < 0.022 + 0.005
0.017 < p < 0.027
(0.017,0.017)
c) The 99% confidence interval is 0.017 to 0.027