A study was conducted to see if people who use the Internet have also paid to do

Question

A study was conducted to see if people who use the Internet have also paid to download music. In a representative sample of 723 adults who use the Internet, 489 admitted that they have paid to download music. Let p represent the true proportion of all Internet-using adults who have paid to download music. Complete parts a through e below. a. Compute a point estimate of p. b. Set up the null and alternative hypotheses for testing whether the true proportion of all Internet-using adults who have paid to download music exceeds 0.7. c. Compute the test statistic for part b. d. Find the rejection region for the test if=0.05. Select the correct choice below and fill in the answer box(es) to complete your choice. e. Make the appropriate conclusion using the rejection region.

Explanation / Answer

(a) In a sample of 723 adults 489 admitted that they have paid to download music then proportion of these people in the sample = 0.676 which is nothing but the point estimate of p for the whole population

(b) The null hypothesis Ho: p>=0.7 and the alternate hypothesis Ha: p<0.7 which will be a lower tail test.

(c) The test statistic we will use is a z test:

z= Pbar-Po / SQRT( Po *(1-Po)/n) = 0.676 - 0.7/ SQRT(0.7*0.3/723) = -1.4

So looking up the z dist table area to the left of z =-1.4 = 0.08 = pvalue

(d) So for a value of 0.08, pvalue>alpha which is 0.05, hence we do not reject the null hypothesis and conclude that p >=0.7 for the population

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

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