In: Statistics and Probability
Use the following information for questions 27-30: A researcher is creating a new treatment protocol for Myelodysplastic Syndrome (MDS), a form of preleukemia. Following the old treatment protocol, 33% of patients with MDS will develop Leukemia within 5 years of MDS diagnosis. He believes his new treatment protocol will lead to fewer MDS patients developing Leukemia. He takes a random sample of 100 individuals on his new treatment protocol. Of these 100 individuals, 27 develop Leukemia within 5 years of MDS diagnosis. The researcher decides to conduct the appropriate hypothesis test using α (alpha) = 0.05. Assume all conditions are met.
Which of the following below best describes the p-value?
| a. | 
 p-value = 0.8997  | 
|
| b. | 
 p-value = 0.2006  | 
|
| c. | 
 0.10 < p-value < 0.15  | 
|
| d. | 
 p-value = 0.1003  | 
|
| e. | 
 0.20 < p-value < 0.30  | 
Solution :
Given that,
= 0.33
1 - 
 = 0.67
n = 100
x = 27
Level of significance = 
 = 0.0
Point estimate = sample proportion = 
 = x / n = 0.27
This a left (One) tailed test.
The null and alternative hypothesis is,
Ho: p = 0.33
Ha: p < 0.33
Test statistics
z = (
- 
 ) / 
*(1-
)
/ n
= ( 0.27 - 0.33) / 
 (0.33*0.67) / 100
= -1.28
P-value = P(Z < z )
= P(Z < -1.276)
= 0.1003
c) 0.10 < p-value < 0.15
The p-value is p = 0.1003, and since p = 0.1003 > 0.05, it is concluded that fail to reject the null hypothesis.