I know it says one question per post but i do not want to post 9 questions when
ID: 3218471 • Letter: I
Question
I know it says one question per post but i do not want to post 9 questions when the last 4 i have posted have yet to be answered and i do not have a lot left.
Bonus Problem Homework 9 Name: ID: The ability of a confidence interval to contain the value of the population mean u is described by the 2. If a confidence level of 90% is used to construct a confidence interval for the mean u of a normal population when the value of the standard deviation o is known, the z critical value is 3. The z curve is often called the t curve with degrees of freedom equal to 4. The area under a t-density curve between the critical values -t and t is a/2 5. When is the mean of a random sample of size n (n is small) from a normal population with mean u, the random variable T X-A) os/Vn) has a probability distribution called t distribution with n-1 6. Which of the following statements are true? A. The interval Xt1.96-o/ n is random, while its width is not random B. The interval n is not random, while its width is random C. The interval -1.96. n is random, while its width is not random D. The interval n is not random, while its width is random E. None of the above statements are true. 7. Which of the following statements are not true? A. A correct interpretation of a 10001-a)% confidence interval for the mean u relies on the long-run frequency interpretation of probability B. It is correct to write a statement such as PLAu lies in the interval (70,80)] .95 c. The probability is .95 that the random interval Tt1.96.a/vn ncludes or covers the true value of u. D. The interval 1.645.0/ n is a 90% confidence interval for the mean u. E. None of the above statements are true. 8. If the width of a confidence interval for u is too wide when the population standard deviation a is known, which one of the following is the best action to reduce the interval width? A. Increase the confidence level B. Reduce the population standard deviation o C. Increase the population mean Au D. Increase the sample size n E. None of the above answers are correct.Explanation / Answer
1) The ability of an interval estimate to contain the value of the population parameter is described by the Confidence level .
2) If a confidence level of 90% is used to construct a confidence interval for the mean of a normal population when standard deviation is known the z critical value is 1.645
3 ) The z curve is often called t curve the degrees of freedom equal to one