Reference no: EM132164480

1. For large random samples, when we look at sample means or proportions, What happens to the width of a confidence interval when the confidence level is increased from 68% to 95% (holding all else constant)? Explain briefly.

2. We randomly select 1000 adults from a population of 2 million and also randomly select 1000 adults from a population of 20 million. If the sample standard deviations are the same, how will the margins of error compare for 95% confidence intervals for the true population average? Will the margin of error for the sample from the larger population be greater than, the same, or less than the margin of error for the sample from the smaller population? Explain briefly.