Chapter 8, Problem 132H

Public Policy Polling recently conducted a survey asking adults across the U.S. about music preferences. When asked,

80 of the 571, participants admitted that they have illegally downloaded music.

a. Create a 99% confidence Irnerval for the tnie proportion of American adults who have Illegally downloaded music.

b. This survey was conducted through automated telephone Interviews on May 6 and 7. 2013. The error bound of the survey compensates for sampling enor, or natural vajlabllltv among samples. List some factors that could affect the suive s outcome that are no covered b the margin of error.

c. Without perfotming any calculations, describe how the confidence interval would change If the confidence level changed from 990 1090%.