# Question

So far at your new job, you have landed nine sales contracts with an average price of $3,782 and a standard deviation of $1,290.

a. Identify a reasonable idealized population that this sample represents.

b. If the distribution of sales prices is heavily skewed, would it be appropriate to construct the usual two-sided 95% confidence interval? Why or why not?

c. Assume now that the distribution of sales prices is only slightly skewed and not too different from a normal distribution. Compute the usual two-sided 95% confidence interval, and interpret it carefully in terms of your long-term prospects at this job. Be sure to address both the useful information and the limitations of the confidence interval in this situation.

d. Find the two-sided 90% prediction interval for the sales price of the next contract you land, assuming that conditions will remain essentially unchanged.

a. Identify a reasonable idealized population that this sample represents.

b. If the distribution of sales prices is heavily skewed, would it be appropriate to construct the usual two-sided 95% confidence interval? Why or why not?

c. Assume now that the distribution of sales prices is only slightly skewed and not too different from a normal distribution. Compute the usual two-sided 95% confidence interval, and interpret it carefully in terms of your long-term prospects at this job. Be sure to address both the useful information and the limitations of the confidence interval in this situation.

d. Find the two-sided 90% prediction interval for the sales price of the next contract you land, assuming that conditions will remain essentially unchanged.

## Answer to relevant Questions

A random sample of 50 recent patient records at a clinic shows that the average billing per visit was $53.01 and the standard deviation was $16.48. a. Find the 95% confidence interval for the mean and interpret it. b. Find ...Vaccine responses have been observed for 1,859 people. Find the appropriate t value from the t table to use for each of the following confidence interval calculations: a. Two-sided 95% confidence. b. Two-sided 99% ...Now look at the entire population of salaries, which you can’t usually do in real life. a. Find the population mean and standard deviation, and compare them to the sample estimates from the previous problem. b. Draw a ...1. Is it proper to multiply the average order size, $42.33, by the number of addresses (1,300,000) in the target mailing? 2. Is it better, as suggested, to multiply the endpoints of the confidence interval by the target ...a. What is Student’s t test? b. Who was Student? What was his contribution?Post your question

0