Question

1.Simulate 100 confidence intervals with a 90% confidence level. Choose a sample size between 2 and 20. Look at your confidence intervals. Take note of their width. Now increase the sample size to something between 30 and 100. Look at your confidence intervals. Finally, increase your sample size to 1000. Look at your confidence intervals. How does sample size affect your confidence intervals? Explain.

2. Simulate 100 confidence intervals with a 90% confidence level. Choose a sample size between 30 and 100. Look at your confidence intervals. Now increase the confidence level to 95%. Look at your confidence intervals. Finally, increase the confidence level to 99%. Look at your confidence intervals. How does the confidence level affect your confidence intervals?

Answer 1

1.The true size of population does not effect the confidence interval. The interval from large samples leads to the narrow width which results in more precise estimates. the width of the confidence interval will be decreased when their is increase in sample because it decreases the standard error. After achieving a specific example estimate lessened returns happen so it does not merit expanding our example measure any further.So here as sample increases and reaches 1000 the estimation of certainty interval will decrease.