A survey of Internet users reported that 15% downloaded music onto their computers. The filing of lawsuits by the recording industry may be a reason why this percent has decreased from the estimate of 33% from a survey taken two years before. Suppose we are not exactly sure about the sizes of the samples. Perform the calculations for the significance tests and 95% confidence intervals under each of the following assumptions. (Use previous - recent. Round your test statistics to two decimal places and your confidence intervals to four decimal places.)
(i) Both sample sizes are 1000.
z=
95% C.I. (_____,_____)
(ii) Both sample sizes are 1600.
z=
95% C.I. (_____,_____)
(iii) The sample size for the survey reporting 33% is 1000 and the sample size for the survey reporting 15% is 1600.
z=
95% C.I. (_____,_____)
Summarize the effects of the sample sizes on the results.