As part of a staged rollout, a new email client was installed on some of the computers of a major company's customer service representatives (CSRS). These CSRS have complained to management saying that the new client is much worse than the old one. One of the company's performance analysts has been tasked with determining if on the busiest day of the year the mean time (in minutes) spent working on email for CSRS using the new email client is greater than the mean time (in minutes) spent working on email for CSRS using the old email client. On the busiest day of the year, the performance analyst studies a random sample of 16 CSRS using the new email client and a random sample of 18 CSRS using the old email client. (These samples are chosen independently.) Each CSR records the amount of time (in minutes) they spend working on email. These data are shown in the table. Times working on email (in minutes) New email client 184, 188, 177, 181, 176, 160, 181, 173, 191, 166, 166, 185, 163, 182, 174, 176 Old email client 191, 188, 146, 129, 169, 150, 163, 123, 80, 226, 171, 236, 115, 179, 155, 97, 82, 195| Send data to calculator v Send data to Excel Assume that the populations of times are approximately normally distributed. Can the performance analyst conclude, at the 0.01 level of significance, that the population mean of the times spent working on email that day for CSRS using the new email client is greater than the population mean of the times spent working on email that day for CSRS using the old email client?

A coin-operated coffee machine made by BIG Corporation was designed to discharge a mean of 7.0 ounces of coffee per cup. If it dispenses more than that on average, the corporation may lose money, and if it dispenses less, the customers may complain. Believing that the mean amount of coffee dispensed by the machine, u, is greater than 7.0 ounces, BIG plans to do a statistical test of the claim that the machine is working as designed. Technicians gather a random sample of fill amounts and find that the mean of the sample is 7.4 ounces and that the standard deviation is 0.3 ounces. Based on this information, answer the questions below. What are the null hypothesis (H) and the alternative hypothesis (H,) that should be used for the test? H: u is ? Η: μs7 In the context of this test, what is a Type I error? v the hypothesis that u is ? ? v. A Type I error is ? v|? when, in fact, u is ? Suppose that BIG decides to reject the null hypothesis. What sort of error might it be making? ?

A consumer advocacy group conducts a large study on car rental practices. Among other things, the group would like to do a statistical test on the mean monthly mileage,μ, of cars rented in the US this year. The consumer advocacy group has good reason to believe that the average monthly mileage for rental cars in the US this year is higher than last year's average, which was2700miles. The group plans to perform a statistical test on the value ofu. To do this, choose a random sample of miles driven per month and calculate that the sample mean is2835miles and the standard deviation is750miles. Use this information to complete the parts below. (to) What are the null hypothesesh and the alternative hypothesish, What should be used to perform the test? h :0 0 (b) (c) h :0 1 Assume that the group decides not to reject the null hypothesis. What kind of mistake could you be making? (Choose an option) Suppose the true average monthly mileage for rental cars in the US this year is2850. Fill in…

Nature lovers’ association of Australia, launched a campaign to encourage paper less communication and/or recycling of used papers to save the trees to reduce global warming. Hence, many small businesses have scaled up their business such as new forms of online document exchanges and collecting used papers and cardboards from households and companies. Abita Recycling Ltd is one such company which is operates in Melbourne. The financial analysist of the company has estimated that the firm would make a profit if the mean weekly collection of papers and cardboards from each household exceeded 1KG. To examine the feasibility of a recycling plant, a random sample of 100 households was selected and sample mean and standard deviations are 1.1KG and 0.35KG respectively. Following the 6-step process of hypothesis testing, you are required to examine do this information provide sufficient evidence at 99% confidence to allow the analyst to conclude that a recycling plant would be profitable?

An important measure in the study of contagious infectious diseases is the number of cases directly generated by one previous case. Jessica is an epidemiologist studying the spread of an infectious disease in her country. She claimed that the mean number of cases directly generated by one previous case is now greater than 1.2. A study of 12 randomly selected cases of the disease is conducted and finds the sample mean number of cases directly generated by one previous case to be 1.5 with a sample standard deviation of 0.7. Assume that the population of the number of cases directly generated by one previous case is approximately normally distributed. Complete the parts below to perform a hypothesis test to see if there is enough evidence, at the 0.10 level of significance, to support the claim that u, the mean number of cases directly generated by one previous case, is greater than 1.2. (a) State the null hypothesis H, and the alternative hypothesis H, that you would use for the test.…

You're a healthcare analytics professional working for Pawhuska, Oklahoma's fourth-largest hospital. You're examining the amount of waiting time that patients classified as ES5 (those with ailments that are not life-threatening) spend in the emergency room. You'll make some changes to emergency room procedures if you find that the mean ES5 waiting time is longer than 18 minutes, the industry standard. Based on a sample of 22 ES5 patients, you found an average and standard deviation of waiting times to be 19.2 minutes and 2.4 minutes, respectively. Draw basic conclusions with the CRITICAL VALUE APPROACH with 99% confidence. Р What is the probability that you conclude that no changes in the emergency room are needed when the actual waiting time for ES5 patients is 20 minutes?

The U.S. Golf Association provides a number of services for its members. One of these is the evaluation of golf equipment to make sure that the equipment satisfies the rules of golf. For example, they regularly test the golf balls made by the various companies that sell balls in the United States. Recently they undertook a study of two brands of golf balls with the objective to see whether there is a difference in the mean distance that the two golf ball brands will fly off the tee. To conduct the test, the U.S.G.A. uses a robot named "ron Byron," which swings the club at the same speed and with the same swing pattern each time it is used. The following data reflect sample data for a random sample of balls of each brand.

As part of a staged rollout, a new email client was installed on some of the computers of a major company's customer service representatives (CSRS). One of the company's performance analysts has been tasked with estimating the difference on the busiest day of the year between the mean time (in minutes) spent working on email for CSRS using the new email client and the mean time (in minutes) spent working on email for CSRS using the old email client. On the busiest day of the year, the performance analyst studies a random sample of 16 CSRS using the new email client and a random sample of 18 CSRS using the old email client. (These samples are chosen independently.) The analyst records the amount of time (in minutes) each CSR spends working on email. These data are shown in the table. Times working on email (in minutes) New email client 166, 188, 207, 172, 202, 148, 192, 173, 197, 197, 158, 172, 209, 185, 203, 169 Old email client 78, 196, 145, 195, 109, 85, 95, 138, 232, 47, 146, 122,…

The dataset HollywoodMovies - 2e contains information on 970 movies that came out of Hollywood between 2007 and 2013. One of the variables is the budget (in millions of dollars) to make the movie. What would be the relevant parameter and statistic for this problem (think -- is this categorical or quantitative)? O u: The mean budget of all Hollywood Movies made between 2007 and 2013. O p: The average proportion of budgets of Hollywood Movies made between 2007 and 2013. T: The mean budget of all Hollywood Movies made between 2007 and 2013. Op: The proportion of Hollywood Movies made between 2007 and 2013.

A consumer advocacy group is doing a large study on car rental practices. Among other things, the consumer group would like to do a statistical test regarding the mean monthly mileage, µ, of car rented in the U.S. this year. The consumer group has reason to believe that the mean monthly mileage of cars rented in the U.S. this year is different from last year’s mean, which was 2700 miles. The group plans to do a statistical test regarding the value of µ. It chooses a random sample of monthly mileages and computes the mean of the sample to be 2565 miles and the standard deviation to be 800 miles. What are the null hypothesis  (H0)  and the alternative hypothesis (H1) that should be used for the test? H0: µ is ____                 __? __ H1: µ is ____                 __ ? ___ In the context of this test, what is a Type II error? A Type II error is ?________       ___ the hypothesis that µ is ? _____  ? when, in fact, µ is ? ____ Suppose that the group decided to reject the null…