Question

8- Suppose that you have two populations: - Population A: you do not know the distribution,...

8- Suppose that you have two populations: - Population A: you do not know the distribution, mean, and the variance of the population. - Population B: you do not know the distribution and the mean of the population. But you know the variance of the population. Now you want to build a %90 confidence level interval for the mean of each population separately by sampling. What is the difference between the methods you use for each population?

Homework Answers

Answer #1

Without loss of generality, if the sample size is sufficiently large, we can assume that the two populations are normally distributed.

Now, for population A, the mean and variance are unknown.

For population B, the mean is unknown but the variance is known.

Now, in order to construct the confidence interval for the mean of each population, we do know the variance for population B, but we do not know the variance for population A. We need to use the sample variance as an estimate of population variance in population A.

So, we have to build a confidence interval based on t-test (i.e. t-distribution should be used) for population A and based on z-test (i.e. standard normal distribution should be used) for Population B.

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Suppose that you have two populations: - Population A: you do not know the distribution, mean,...
Suppose that you have two populations: - Population A: you do not know the distribution, mean, and the variance of the population. - Population B: you do not know the distribution and the mean of the population. But you know the variance of the population. Now you want to build a %90 confidence level interval for the mean of each population separately by sampling. What is the difference between the methods you use for each population??
Suppose that we want to test the null hypothesis that the mean of population 1 is...
Suppose that we want to test the null hypothesis that the mean of population 1 is equal to the mean of population 2. We select a random sample from population 1 and a random sample from population 2, and these two samples are independent. Circle the FALSE statement. A. We need to perform a two-sided test. B. If we know the variance of each population, even if they are different, we can use the Z test. That is, the test...
Suppose we are comparing two populations to see if they have the same mean. A sample...
Suppose we are comparing two populations to see if they have the same mean. A sample from each population is taken and the difference in means was 12 Suppose a test of the hypothesis that the difference is zero has a p-value of 0.0156. Which of the following are true statements (circle all that are true): a The two-sided 99% confidence interval includes zero. b The one-sided 99% confidence interval includes zero. c The hypothesis that they are equal would...
Suppose we are comparing two populations to see if they have the same mean. A sample...
Suppose we are comparing two populations to see if they have the same mean. A sample from each population is taken and the difference in means was 12. Suppose a test of the hypothesis that the difference is zero has a p-value of 0.0156. Which of the following are true statements (list all that are true): a. The two-sided 99% confidence interval includes zero. b. The one-sided 99% confidence interval includes zero. c. The hypothesis that they are equal would...
You are comparing two population means, say population A and population B. By doing that, you...
You are comparing two population means, say population A and population B. By doing that, you are calculating a 90% confidence interval for the difference means for sample A and sample B. This 90% confidence interval yields μA - μB = (-2.876, 5.398) Based on this 90% confidence interval, a student concluded that the mean of population A is more than the mean of population B. True False
Suppose you want to determine whether the average values for populations 1 and 2 are different,...
Suppose you want to determine whether the average values for populations 1 and 2 are different, and you randomly gather the following data. sample 1 2, 11, 7, 8, 2, 5, 9, 1, 9, 1, 5, 8, 11, 2, 5, 5, 6, 9 sample 2 10, 12, 8, 12, 9, 12, 9, 7, 9, 10, 11, 10, 11, 10, 7, 8, 10, 10 Test your conjecture, using a probability of committing a Type I error of .01. Assume the population...
Suppose you have selected a random sample of ?=14 measurements from a normal distribution. Compare the...
Suppose you have selected a random sample of ?=14 measurements from a normal distribution. Compare the standard normal ? values with the corresponding ? values if you were forming the following confidence intervals. (a)    90% confidence interval z= t= (b)    95% confidence interval z=   t= (c)    98% confidence interval ?= t= 2) A confidence interval for a population mean has length 20. a) Determine the margin of error. b) If the sample mean is 58.6, obtain the confidence interval. Confidence interval: ( ,...
Consider the following results for independent samples taken from two populations. Sample 1 Sample 2 n1...
Consider the following results for independent samples taken from two populations. Sample 1 Sample 2 n1 = 500 n2= 200 p1= 0.45 p2= 0.34 a. What is the point estimate of the difference between the two population proportions (to 2 decimals)? b. Develop a 90% confidence interval for the difference between the two population proportions (to 4 decimals). Use z-table. to c. Develop a 95% confidence interval for the difference between the two population proportions (to 4 decimals). Use z-table....
Consider the following results for independent samples taken from two populations. Sample 1 Sample 2 n1...
Consider the following results for independent samples taken from two populations. Sample 1 Sample 2 n1 = 500 n2= 300 p1= 0.43 p2= 0.36 a. What is the point estimate of the difference between the two population proportions (to 2 decimals)? b. Develop a 90% confidence interval for the difference between the two population proportions (to 4 decimals). Use z-table. to c. Develop a 95% confidence interval for the difference between the two population proportions (to 4 decimals). Use z-table....
Consider the following results for independent samples taken from two populations. Sample 1 Sample 2 n1...
Consider the following results for independent samples taken from two populations. Sample 1 Sample 2 n1 = 500 n2= 200 p1= 0.46 p2= 0.31 b. Develop a 90% confidence interval for the difference between the two population proportions (to 4 decimals). Use z-table. ______ to ________ c. Develop a 95% confidence interval for the difference between the two population proportions (to 4 decimals). Use z-table. ________ to _________
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT