Question

Nexium is a drug that can be used to reduce the acid produced by the body and heal damage to the esophagus due
to acid reflux. The manufacturer of Nexium in advertising states that more than 94% of patients taking Nexium
are healed within 8 weeks. In clinical trials, 96% out of 300 patients suffering from acid reflux disease were
healed after 8 weeks. Run a hypothesis test at the α = 0.01 and α = 0.10 significance level to test whether the
advertising is true.
H0: _____ = 0.94 [fill in the blanks]
Ha: _____ _____ 0.94 [fill in the blanks]
a. Follow our procedure on page 2 of our Unit 3 Day 1 notes to bracket the claim, etc.
b. Which word, phrase or symbol in the claim determines the inequality in the alternative hypothesis:
_________________
c. Which word, phrase or information (or lack of information) in the problem tells us that this problem
involves a test for the proportion, and not a mean? _______________________________________________
d. Fill in the hypothesis.
e. Explain why the number “0.96” does not appear in the hypothesis: _______________________
_____________________________________________________________________________________
f. The p-value is 0.072. Find the outcome of the test and write a plain English interpretation of the outcome
using both α = 0.05 and α = 0.10.

Answer 1

a. Claim : The manufacturer of Nexium in advertising states that more than 94% of patients taking Nexium
are healed within 8 weeks.

b. Which word, phrase or symbol in the claim determines the inequality in the alternative hypothesis:
More than 94%

c. Which word, phrase or information (or lack of information) in the problem tells us that this problem
involves a test for the proportion, and not a mean?

Claim states that more than 94% of patients taking Nexium are healed within 8 weeks , so it represents the Population proportion of patients taking Nexium are healed within 8 weeks.

d. Fill in the hypothesis.

H0: P = 0.94
Ha: P > 0.94

e. Explain why the number “0.96” does not appear in the hypothesis:

The hypothesis gives the information about the Population parameter , here population parameter is population proportion P = 0.94 ;

0.96 is a sample proportion of sample size 300 , therefore it does not appear in the hypothesis.

f. The p-value is 0.072. Find the outcome of the test and write a plain English interpretation of the outcome
using both α = 0.05 and α = 0.10.

For α = 0.05 , As P value is greater than 0.05 ,we fail to reject the null hypothesis , there is no sufficient evidence that more than 94% of patients taking Nexium are healed within 8 weeks.

Interpretation : advertising is not true.

For α = 0.1 , As P value is less than 0.05 ,we reject the null hypothesis , there is sufficient evidence that more than 94% of patients taking Nexium are healed within 8 weeks.

Interpretation : advertising is true.