Exam 19: Questions that Involve Online Topics

Using the Studentized residuals tᵢ to determine influential points in a multiple regression model with k independent variable and n observations and letting tn₋k₋₂ denote the upper critical value of a two-tail t test with a 0.10 level of significance,Xᵢ is an influential point if

TABLE 19-4 A stock portfolio has the following returns under the market conditions listed below. Market Condition Probability Return Bull 0.4 $200 Stable 0.3 $100 Bear 0.3 -$100 -Referring to Table 19-4,what is the EMV?

TABLE 19-1 The following payoff table shows profits associated with a set of 3 alternatives under 2 possible states of nature. -Referring to Table 19-1,what is the best action using the maximin criterion?

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,what are the lower and upper critical values of the test?

The Paasche price index is a form of unweighted aggregate price index.

TABLE 16-2 Given below are the prices of a basket of four food items from 2006 to 2010. -Referring to Table 16-2,what are the simple price indices for wheat,corn,soybeans and milk,respectively,in 2008 using 2006 as the base year?

For a potential investment of $5,000,a portfolio has an EMV of $1,000 and a standard deviation of $100.The return to risk ratio is

For a given level of significance,if the sample size is increased but the summary statistics remain the same,the probability of committing a Type II error will increase.

TABLE 16-1 Given below are the average prices for three types of energy products for five consecutive years. -Referring to Table 16-1,what is the Paasche price index for the group of three energy items in 2004 for a family that consumed 13 units of electricity,26 units of natural gas and 235 units of fuel oil in year 3 using year 1 as the base year?

TABLE 19-1 The following payoff table shows profits associated with a set of 3 alternatives under 2 possible states of nature. -Referring to Table 19-1,if the probability of S1 is 0.5,then the coefficient of variation for A2 is

A company that manufactures designer jeans is contemplating whether to increase its advertising budget by $1 million for next year.If the expanded advertising campaign is successful,the company expects sales to increase by $1.6 million next year.If the advertising campaign fails,the company expects sales to increase by only $400,000 next year.If the advertising budget is not increased,the company expects sales to increase by $200,000.Identify the payoffs in this decision-making problem.

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 EOL for Action A?

TABLE 8-2 A wealthy real estate investor wants to decide whether it is a good investment to build a high-end shopping complex in a suburban county near Chicago.His main concern is the total market value of the 3,605 houses in the suburban county.He commissioned a statistical consulting group to take a sample of 200 houses and obtained a sample mean market price of $225,000 and a sample standard deviation of $38,700.The consulting group also found out that the mean differences between market prices and appraised prices was $125,000 with a standard deviation of $3,400.Also the proportion of houses in the sample that are appraised for higher than the market prices is 0.24. -Referring to Table 8-2,what will be the 90% confidence interval for the total difference between the market prices and appraised prices of the houses in the suburban county constructed by the consulting group?

A company that manufactures designer jeans is contemplating whether to increase its advertising budget by $1 million for next year.If the expanded advertising campaign is successful,the company expects sales to increase by $1.6 million next year.If the advertising campaign fails,the company expects sales to increase by only $400,000 next year.If the advertising budget is not increased,the company expects sales to increase by $200,000.Identify the actions in this decision-making problem.

TABLE 6-1 A company has 125 personal computers.The probability that any one of them will require repair on a given day is 0.15. -Referring to Table 6-1 and assuming that the number of computers that requires repair on a given day follows a binomial distribution,compute the probability that there will be more than 25 but less than 30 computers that require repair on a given day using a normal approximation.

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 incorrectly marketing the new local anesthetic when its population mean effective time is not greater than the 7.4 minutes is ________.

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 return to risk ratio for Action B?

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 0.01,the probability of the operations manager incorrectly stopping the process if the population mean bulb life is 510 hours is ________.

TABLE 7-1 Times spent studying by students in the week before final exams follow a normal distribution with standard deviation 8 hours.A random sample of 4 students was taken from a population of 50 in order to estimate the mean study time for the population of all students.Use the finite population correction. -Referring to Table 7-1,90% of all the samples of 4 will have a sample mean of no more than how many hours from the population mean?

The Analysis of Proportion (ANOP)is more appropriate if you want to identify the group(s)that has(have)a higher or lower proportion than the overall average proportion while the chi-square test for the difference among more than two proportions is more appropriate when you just want to see if the proportions of all the different groups are the same.