Rhino viruses typically cause common colds. In test of the effectiveness of echi

Question

Rhino viruses typically cause common colds. In test of the effectiveness of echinacea, 35 of the 40 subjects treated with echinacea developed rhinovirus infections. In a placebo group, 77 of the 90 subjects developed rhinovirus infections. Construct a 95% confidence interval for the difference between the proportion of people who the develop rhinovirus infections and are treated with echinacea and those who develop rhinovirus infection but are not treated with echinacea. The 95% confidence interval is

Explanation / Answer

The statistical software output for this problem is:

Two sample proportion confidence interval:
p1 : proportion of successes for population 1
p2 : proportion of successes for population 2
p1 - p2 : Difference in proportions
Note: the standard error is calculated using separate estimates for the proportions

95% confidence interval results:

Hence,

95% confidence interval will be:

-0.106 < p1 - p2 < 0.145

Difference Count1 Total1 Count2 Total2 Sample Diff. Std. Err. L. Limit U. Limit p1 - p2 35 40 77 90 0.019444444 0.064089694 -0.10616905 0.14505794

Related Questions

Navigate

• Browse (All)
• Browse R
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.