Question

testing mean with unknown sigma

testing mean with unknown sigma

Math   Statistics-And-Probability   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

If sigma (population standard deviation is unknown), t- distribution can be used.

Example:

thank you.

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Testing a Claim about a mean (σ unknown) Suppose the EPA was suing the city of...
Testing a Claim about a mean (σ unknown) Suppose the EPA was suing the city of Rochester for non-compliance with carbon monoxide standards. Specifically, the EPA would want to show that the mean level of carbon monoxide levels in downtown Rochester’s air is dangerously high, higher than 4.9 parts per million. Does a random sample of 22 readings (sample results: xbar=5.25 and s=1.17) present sufficient evidence to support the EPA’s claim? Use α = 0.05.
Hypothesis testing (Test only for mean when standard deviation is unknown) Let X. be a random...
Hypothesis testing (Test only for mean when standard deviation is unknown) Let X. be a random variable representing dividend yield of Australian bank stocks. We may assume that X has a normal distribution with ? = 24%. A random sample of 10 Australian bank stocks bank stocks gave the following yields: 7.1, 5.5, 4.8, 6.0, 4.9, 4.0, 3.4, 8.5, 5.3, 6.1 ? ( =5.38%. For the entire Austrian stock’s markets, the mean dividend yield is ? =4.7%. Do these data...
Assume that the medical scores of a drug follow normal model with an unknown mean and...
Assume that the medical scores of a drug follow normal model with an unknown mean and a variance of 2. If a clinical trial needs to control the type I error at 0.05 and the type II error at 0.10 for testing the unknown mean score equals 2 versus 4, at least how many patients should be recruited in the study.
Basic Computation: Testing u, o Unknown: A random sample has 49 values. The sample mean is...
Basic Computation: Testing u, o Unknown: A random sample has 49 values. The sample mean is 8.5 and the sample standard deviation is 1.5. Use a level of significance of 0.01 to conduct a left-tailed test of the claim that population mean is 9.2 (a)Check Requirements Is it appropriate to use a Student’s t distribution? Explain. How many degrees of freedom do we use? (b) What are the hypotheses? (c) Compute the sample test statistic t. (d) Estimate the P-value...
Let X1,....,XN be a random sample from N(Mu, sigma squared). Both parameters unknown. a) Give two...
Let X1,....,XN be a random sample from N(Mu, sigma squared). Both parameters unknown. a) Give two pivotal quantities based on the sufficient statistics and determine their distribution functions. The best solutions are those you can use to construct confidence intervals for Mu and sigma squared. b) If a random sample of size 5 is observed as follows: 9.67, 10.01, 9.31, 9.33, 9.28, find a 95% equal tailed confidence interval for sigma squared. c) Based on the above observations, find a...
Question 7: Hypothesis Testing - Two-Sided, Unknown Population Variance A process produces cable for the local...
Question 7: Hypothesis Testing - Two-Sided, Unknown Population Variance A process produces cable for the local telephone company. When the process is operating correctly, cable diameter follows a normal distribution with mean 1.6 inches. A random sample of 16 pieces of cable found diameters with sample mean of 1.615 inches and sample standard deviation of 0.05. Test, at the 10% level against a two-sided alternative, the null hypothesis that the population mean is 1.6 inches.
X1 is normal with mean mu and variance sigma^2. X2 is normal with mean mu and...
X1 is normal with mean mu and variance sigma^2. X2 is normal with mean mu and variance 2sigma^2. Consider the estimator cX1 + (1-c)X2. For what value of c is the variance minimized?
A population has a mean mu=86 and a standard deviation sigma=22. Find the mean and standard...
A population has a mean mu=86 and a standard deviation sigma=22. Find the mean and standard deviation of a sampling distribution of sample means with sample size n=248.
A sample from a Normal distribution with an unknown mean µ and known variance σ =...
A sample from a Normal distribution with an unknown mean µ and known variance σ = 45 was taken with n = 9 samples giving sample mean of ¯ y = 3.6. (a) Construct a Hypothesis test with significance level α = 0.05 to test whether the mean is equal to 0 or it is greater than 0. What can you conclude based on the outcome of the sample? (b) Calculate the power of this test if the true value...
1. To estimate the mean of a population with unknown distribution shape and unknown standard deviation,...
1. To estimate the mean of a population with unknown distribution shape and unknown standard deviation, we take a random sample of size 64. The sample mean is 22.3 and the sample standard deviation is 8.8. If we wish to compute a 92% confidence interval for the population mean, what will be the t multiplier? (Hint: Use either a Probability Distribution Graph or the Calculator from Minitab.)
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT