Match the correct answers for the following problem. You take a SRS of 23 men's incomes and find a sample mean of 46.18 thousand dollars with a sample standard deviation of 10.33 thousand dollars. You take a SRS of 40 women's incomes and find a sample mean of 40.69 thousand dollars with a sample standard deviation of 10.89 thousand dollars. Find the 95% Confidence Interval for the difference in the (population) means of men's income minus women's income. (So men's income is 1st) The lower bound for the CI is Choose... The upper bound for the CI is Choose...
Added by Anthony B.
Close
Step 1
Standard error = sqrt((s1^2/n1) + (s2^2/n2)) Standard error = sqrt((10.33^2/23) + (10.89^2/40)) Standard error = sqrt((106.7089/23) + (118.5921/40)) Standard error = sqrt(4.6417 + 2.9648) Standard error = sqrt(7.6065) Standard error ≈ 2.759 Show more…
Show all steps
Your feedback will help us improve your experience
Adi S and 92 other Intro Stats / AP Statistics educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
In the second quarter of the previous year, the census bureau surveyed over n = 324 men and n = 256 women to determine their average weekly earnings. In their analysis, the usual weekly earnings for males was $938 and the average usual weekly earnings of women was $779. Historically, the population standard deviation for men is lower (Δ = 450) than women (Δ = 480). Compute a 90%, 95%, and 99% confidence interval around the mean weekly earnings for males. Match the following values with the correct descriptive statistics for various confidence: M = SE = Lower 90% CI = Upper 90% CI = Lower 95% CI = Upper 95% CI = Lower 99% CI = Upper 99% CI =
Adi S.
Construct the indicated confidence interval for the difference between the two population means. Assume that the two samples are independent simple random samples selected from normally distributed populations. Also assume that the population standard deviations are equal (σ1 = σ2), so that the standard error of the difference between means is obtained by pooling the sample variances. A researcher was interested in comparing the amount of time spent watching television by women and by men. Independent simple random samples of 14 women and 17 men were selected and each person was asked how many hours he or she had watched television during the previous week. The summary statistics are as follows. Construct a 95% confidence interval for μ1 - μ2, the difference between the mean amount of time spent watching television for women and the mean amount of time spent watching television for men.
Madhur L.
Suppose we are given survey data on the body mass index (BMI) of 654 young women. The mean BMI in the sample was x = 26.7. We treat these data as an SRS from a Normally distributed population with standard deviation σ = 9.5. (a) Suppose that we had an SRS of just 100 young women. What would be the margin of error for 95% confidence? (Enter your answer to three decimal places.) (b) Find the margins of error for 95% confidence based on SRSs of 400 young women and 1600 young women. (Enter your answers to four decimal places.) n = 400 n = 1600 (c) Compare the three margins of error. How does increasing the sample size change the margin of error of a confidence interval when the confidence level and population standard deviation remain the same? True or False: The larger the sample size, the larger margin of error of a confidence interval. True False
Recommended Textbooks
Elementary Statistics a Step by Step Approach
The Practice of Statistics for AP
Introductory Statistics
Transcript
Watch the video solution with this free unlock.
EMAIL
PASSWORD