9.1 Homework Statistics

A simple random sample of size n = 450 individuals who are currently employed is asked if they work at home at least once per week. Of the 450 employed Prin individuals surveyed, 26 responded that they did work at home at least once per week. Construct a 99% confidence interval for the population proportion of employed individuals who work at home at least once per week. The lower bound is (Round to three decimal places as needed.) The upper bound is . (Round to three decimal places as needed.) 2. Define each of the following terms. (a) Point estimate (b) Confidence interval c) Level of confidence (d) Margin of error Drag each of the terms given above into the appropriate definition below. A range of numbers based on a point estimate of an unknown parameter The expected proportion of intervals that contain the parameter if a large number of different samples is obtained Determines the width of the confidence interval The value of a statistic that estimates the value of a parameter If you constructed one hundred 91% confidence intervals based on one hundred different random samples of size n, how many of the intervals would you expect include the unknown parameter? Assume all model requirements are satisfied Choose the correct answer below. O A. 9 OB. 100 CC. 91 O D. 50 . Put the following in order from narrowest to widest interval. Assume the sample size and sample proportion is the same for all four confidence intervals. (a) 95% confidence interval (b) 87% confidence interval c) 97% confidence interval (d) 80% confidence interval Choose the correct answer below. CA. (d), (b), (a), (c) O B. (c), (b), (a ) , (d ) O c. (c), (a), (b), (d) O D. ( d ) , (a ) , (b ) , (c ) 5. If a sample proportion is 0.68, which of the following could be a 90% confidence interval for the population proportion? Select all that apply. LY A. Lower bound: 0.63; Upper bound: 0.73 B. Lower bound: 0.61; Upper bound: 0.75 C. Lower bound: 0.75; Upper bound: 0.89 D. Lower bound: 0.64; Upper bound: 0.74 E. Lower bound: 0.54; Upper bound: 0.75 YOU ANSWERED: A., D. 6. Compute the critical value Zx /2 that corresponds to a 81% level of confidence. Click here to view the standard normal distribution table (page 1).1 Click here to view the standard normal distribution table (page 2).2 Za/2= (Round to two decimal places as needed.) 1: Standard Normal Distribution Table (page 1) Area Standard Normal Distribution 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09