# Question: A Statistics professor has observed that for several years about

A Statistics professor has observed that for several years about 13 % of the students who initially enroll in his Introductory Statistics course withdraw before the end of the semester. A salesperson suggests that he try a statistics software package that gets students more involved with computers, predicting that it will cut the dropout rate. The software is expensive, and the salesperson offers to let the professor use it for a semester to see if the dropout rate goes down significantly. The professor will have to pay for the software only if he chooses to continue using it. Initially, 203 students signed up for the Statistics course. They used the software suggested by the salesperson, and only 11 dropped out of the course.

a) Is this a one-tailed or two-tailed test? Explain.

b) Write the null and alternative hypotheses.

c) Should the professor spend the money for this software? Support your recommendation with an appropriate test.

d) Explain what your P-value means in this context.

a) Is this a one-tailed or two-tailed test? Explain.

b) Write the null and alternative hypotheses.

c) Should the professor spend the money for this software? Support your recommendation with an appropriate test.

d) Explain what your P-value means in this context.

## Answer to relevant Questions

A company is willing to renew its advertising contract with a local radio station only if the station can prove that more than 20% of the residents of the city have heard the ad and recognize the company’s product. The ...Games for the iPad have a distribution of prices that is skewed to the high end. a) Explain why this is what you would expect. b) Members of the iPad gamers club each own about 50 games. Pat is one such member. What would ...The owner of the store from Exercise wants to know if the mean age of all customers is 25 years old. a) What is the null hypothesis? b) Is the alternative one- or two-sided? c) What is the value of the test statistic? d) ...Describe how the width of a 95% confidence interval for a mean changes as the sample size (n) increases, assuming the standard deviation remains the same. Suppose that for budget planning purposes the city in Exercise 31 needs a better estimate of the mean daily income from parking fees. a) Someone suggests that the city use its data to create a 95% confidence interval ...Post your question