Exam 19: Questions that Involve Online Topics

TABLE 9-2 An appliance manufacturer claims to have developed a compact microwave oven that consumes a population mean of no more than 250 W.From previous studies,it is believed that power consumption for microwave ovens is normally distributed with a population standard deviation of 15 W.If there is evidence that the population mean consumption is greater than 250 W,the manufacturer will be unable to make the claim. -Referring to Table 9-2,if you select a sample of 20 compact microwave ovens and are willing to have a level of significance of 0.05,the probability of making a Type II error is ________ if the mean power consumption of all such microwave ovens is in fact 248 W.

For a given sample size,the probability of committing a Type II error will increase when the probability of committing a Type I error is reduced.

TABLE 9-3 A drug company is considering marketing a new local anesthetic.The effective time of the anesthetic the drug company is currently producing has a normal distribution with a mean of 7.4 minutes with a standard deviation of 1.2 minutes.The chemistry of the new anesthetic is such that the effective time should be normally distributed with the same standard deviation.The company will market the new local anesthetic as being better if there is evidence that the population mean effective time is greater than the 7.4 minutes of the current local anesthetic. -Referring to Table 9-3,if you select a sample of 25 new local anesthetics and are willing to have a level of significance of 0.01,the probability of the company failing to market the new local anesthetic when its population mean effective time is greater than the 7.4 minutes is ________ if the population mean effective time is 8 minutes.

An agronomist wants to compare the crop yield of 3 varieties of chickpea seeds.She plants all 3 varieties of the seeds on each of 5 different patches of fields.She then measures the crop yield in bushels per acre.She has found out that the crop yield from the 3 varieties of seeds has very skewed distribution.Which of the following tests will be the most appropriate to find out if the different patches are advantageous in reducing the random error?

TABLE 8-1 A random sample of 100 stores from a large chain of 500 garden supply stores was selected to determine the mean number of lawnmowers sold at an end-of-season clearance sale.The sample results indicated a mean of 6 and a standard deviation of 2 lawnmowers sold.A 95% confidence interval (5.623 to 6.377)was established based on these results. -Referring to Table 8-1,of all possible samples of 100 stores drawn from the population of 1,000 stores,95% of the sample means will fall between 5.623 and 6.377 lawnmowers.

TABLE 9-2 An appliance manufacturer claims to have developed a compact microwave oven that consumes a population mean of no more than 250 W.From previous studies,it is believed that power consumption for microwave ovens is normally distributed with a population standard deviation of 15 W.If there is evidence that the population mean consumption is greater than 250 W,the manufacturer will be unable to make the claim. -Referring to Table 9-2,if you select a sample of 20 compact microwave ovens and are willing to have a level of significance of 0.01,the power of the test is ________ if the mean power consumption of all such microwave ovens is in fact 248 W.

The risk- ________ curve shows a rapid increase in utility for initial amounts of money followed by a gradual leveling off for increasing dollar amounts.

TABLE 19-6 A student wanted to find out the optimal strategy to study for a Business Statistics exam.He constructed the following payoff table based on the mean amount of time he needed to study every week for the course and the degree of difficulty of the exam.From the information that he gathered from students who had taken the course,he concluded that there was a 40% probability that the exam would be easy. -Referring to Table 19-6,what is the coefficient of variation of spending 8 hours per week on average studying for the exam?

TABLE 9-1 A manufacturer produces light bulbs that have a mean life of at least 500 hours when the production process is working properly.Based on past experience,the population standard deviation is 50 hours and the light bulb life is normally distributed.The operations manager stops the production process if there is evidence that the population mean light bulb life is below 500 hours. -Referring to Table 9-1,if you select a sample of 100 light bulbs and are willing to have a level of significance of 0.05,the probability of the operations manager failing to stop the process when the process is not working properly is ________ if the population mean bulb life is 490 hours.

TABLE 12-1 A perfume manufacturer is trying to choose between 2 magazine advertising layouts.An expensive layout would include a small package of the perfume.A cheaper layout would include a "scratch-and-sniff" sample of the product.The manufacturer would use the more expensive layout only if there is evidence that it would lead to a higher approval rate.The manufacturer presents both layouts to 5 groups and determines the approval rating from each group on both layouts.The data are given below.Use this to test whether the median difference in approval rating is different from zero in favor of the more expensive layout with a level of significance of 0.05. -Referring to Table 12-1,the null hypothesis should be rejected.

Removal of uncertainty from a decision-making problem leads to a case referred to as perfect information.

The difference between expected payoff under certainty and expected value of the best act without certainty is the

TABLE 7-2 According to a survey,only 15% of customers who visited the website of a major retail store made a purchase.Random samples of size 50 are selected from a population of 900.Use the finite population correction factor. -Referring to Table 7-2,90% of the samples will have more than what percentage of customers who will make a purchase after visiting the website?

TABLE 9-3 A drug company is considering marketing a new local anesthetic.The effective time of the anesthetic the drug company is currently producing has a normal distribution with a mean of 7.4 minutes with a standard deviation of 1.2 minutes.The chemistry of the new anesthetic is such that the effective time should be normally distributed with the same standard deviation.The company will market the new local anesthetic as being better if there is evidence that the population mean effective time is greater than the 7.4 minutes of the current local anesthetic. -Referring to Table 9-3,if you select a sample of 25 new local anesthetics and are willing to have a level of significance of 0.1,the probability of a Type II error is ________ if the population mean effective time is 8 minutes.

TABLE 19-2 The following payoff matrix is given in dollars. -Referring to Table 19-2,what is the best action using the maximin criterion?

The Laspeyres price index is a form of weighted aggregate price index.

TABLE 19-5 The following payoff table shows profits associated with a set of 2 alternatives under 3 possible events. -Referring to Table 19-5,what is the optimal action using maximin criterion?

TABLE 9-1 A manufacturer produces light bulbs that have a mean life of at least 500 hours when the production process is working properly.Based on past experience,the population standard deviation is 50 hours and the light bulb life is normally distributed.The operations manager stops the production process if there is evidence that the population mean light bulb life is below 500 hours. -Referring to Table 9-1,if you select a sample of 100 light bulbs and are willing to have a level of significance of 0.05,the probability of the operations manager incorrectly stopping the process when the process is in fact working properly is ________.

TABLE 19-2 The following payoff matrix is given in dollars. -Referring to Table 19-2,the EOL for Action A is

The finite population correction factor is