Decision Support Tools Main Content Quiz Test 2 (S1) Question 1 Answer saved Marked out of 1.00 Question text If we know that the length of time it takes a college student to find a parking spot in the library parking lot follows a normal distribution with a mean of 3.5 minutes and a standard deviation of 1 minute, find the probability that a randomly selected college student will find a parking spot in the library parking lot in less than 3 minutes. Select one: 0.3551 0.3085 0.2674 0.1915 Question 2 Answer saved Marked out of 1.00 Question text True or False: The probability that a standard normal random variable, Z, is less than 50 is approximately 0. Select one: True False Question 3 Answer saved Marked out of 1.00 Question text At a computer manufacturing company, the actual size of computer chips is normally distributed with a mean of 1 centimeter and a standard deviation of 0.1 centimeter. A random sample of 12 computer chips is taken. What is the standard error for the sample mean? Select one: 0.029 0.050 0.091 0.120 Question 4 Answer saved Marked out of 1.00 Question text True or False: Suppose = 80 and 2 = 400 for a population. In a sample where n = 100 is randomly taken, 95% of all possible sample means will fall above 76.71. Select one: True False Question 5 Answer saved Marked out of 1.00 Question text Suppose a 95% confidence interval for has been constructed. If it is decided to take a larger sample and to decrease the confidence level of the interval, then the resulting interval width would __________ . (Assume that the sample statistics gathered would not change very much for the new sample.) Select one: be larger than the current interval width be narrower than the current interval width be the same as the current interval width be unknown until actual sample sizes and reliability levels were determined Question 6 Answer saved Marked out of 1.00 Question text True or False: The t distribution is used to construct confidence intervals for the population mean when the population standard deviation is unknown. Select one: True False Question 7 Answer saved Marked out of 1.00 Question text An entrepreneur is considering the purchase of a coin-operated laundry. The current owner claims that over the past 5 years, the average daily revenue was $675 with a standard deviation of $75. A sample of 30 days reveals a daily average revenue of $625. If you were to test the null hypothesis that the daily average revenue was $675 and decide not to reject the null hypothesis, what can you conclude? Select one: There is not enough evidence to conclude that the daily average revenue was $675. There is not enough evidence to conclude that the daily average revenue was not $675. There is enough evidence to conclude that the daily average revenue was $675. There is enough evidence to conclude that the daily average revenue was not $675. Question 8 Answer saved Marked out of 1.00 Question text True or False: The smaller is the p-value, the stronger is the evidence against the null hypothesis. Select one: True False Question 9 Answer saved Marked out of 1.00 Question text What do we mean when we say that a simple linear regression model is 'statistically' useful? Select one: All the statistics computed from the sample make sense. The model is an excellent predictor of Y. The model is 'practically' useful for predicting Y. The model is a better predictor of Y than the sample mean. Question 10 Answer saved Marked out of 1.00 Question text To assess the adequacy of a forecasting model, one measure that is often used is Select one: quadratic trend analysis. the MAD. exponential smoothing. moving averages. Question 11 Answer saved Marked out of 1.00 Question text 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. Select one: Two choices: (1) increase the budget and (2) do not increase the budget. Two possibilities: (1) campaign is successful and (2) campaign is not successful. Four consequences resulting from the Increase/Do Not Increase and Successful/Not Successful combinations. The increase in sales dollars next year. Information Information text The data below represents the amount of grams of carbohydrates in a sample serving of breakfast cereal. 10 18 24 30 19 22 24 20 18 25 20 22 19 Question 12 Answer saved Marked out of 1.00 Question text The standard deviation for this data would be Answer grams. 4.705 Answer should be between two and four decimal places e.g. 1.23, 1.234, 1.2345 etc. Please do NOT include units (grams) in your answer. Information Information text In a local cellular phone area, company A accounts for 70% of the cellular phone market, while company B accounts for the remaining 30% of the market. Of the cellular calls made with company A, 2% of the calls will have some sort of interference, while 3% of the cellular calls with company B will have interference. Question 13 Not yet answered Marked out of 1.00 Question text If a cellular call is selected at random, the probability that it will have interference is Answer ? Answer should be between two and four decimal places e.g. 0.12, 0.123, 0.1234 etc. Please do NOT include any units in your answer. Information Information text The manager of a service station is in the process of analyzing the number of times car owners change the oil in their cars. She believes that the average motorist changes his or her car's oil less frequently than recommended by the owner's manual (two times per year). In a preliminary survey she asked 15 car owners how many times they changed their car's oil in the last 12 months. The results are listed below. 1 1 2 0 3 3 0 1 0 1 2 3 1 3 1 Question 14 Not yet answered Marked out of 1.00 Question text The value of the test statistic in this problem is approximately equal to Answer ? Answer should be between two and four decimal places e.g. 1.23, 1.234, 1.2345 etc. Please do NOT include any units in your answer. Question 15 Not yet answered Marked out of 1.00 Question text What would be your decision if a hypothesis test was conducted on this problem with the null hypothesis given as H0 : 2 and the alternate hypothesis given as H1 < 2? Select one: Reject H0 at the 10%, 5% and 1% level of significance. Reject H0 at the 10% and 5% level of significance but do not reject H0 at the 1% level of significance. Reject H0 at the 10% level of significance but do not reject H0 at the 5% or 1% level of significance. Do not reject H0 at either the 10%, 5% or 1% level of significance. Information Information text Refer to the following table which contains the sales (in $,000) for a department store for the first ten months of the year. Month Sales January 440 February 480 March 590 April 400 May 500 June 550 July 470 August 500 September 600 October 520 Question 16 Not yet answered Marked out of 1.00 Question text Using a three period moving average (i.e. MA(3)) as a forecasting method, what is the MAPE for this forecasting model Answer % Answer should be to four decimal places e.g. if your answer was 12.34%, you would enter 0.1234 as your answer. Please do NOT include units (%) in your answer. Question 17 Not yet answered Marked out of 1.00 Question text Using simple exponential smoothing (with a smoothing constant of 0.2) as a forecasting method, what is the MSE for this forecast model? Answer should be between two and four decimal places e.g. 1.23, 1.234, 1.2345 etc. Please do NOT include any units in your answer. Answer: Information Information text The ordered list below resulted from taking a sample of 25 batches of 500 computer chips and determining how many in each batch were defective. Defects 1, 2, 4, 4, 5, 5, 6, 7, 9, 10, 12, 12, 14, 17, 20, 21, 23, 23, 24, 26, 27, 27, 28, 29, 29 Question 18 Not yet answered Marked out of 1.00 Question text If a frequency distribution for the defects data is constructed, using '0 but less than 5' as the first class, what would be the relative frequency of the '20 but less than 25' class Answer %? Answer should be a percentage value to whole numbers e.g. 12, 23, 34 etc. Please do NOT include units (%) in your answer. Information Information text A manufacturer of power tools claims that the average amount of time required to assemble their top-of-the-line table saw is fifty (50) minutes with a standard deviation of forty (40) minutes (the very large standard deviation is due to a variety of factors including a large variation in skills amongst the 'Do it yourself' home handyman which is traditionally one of the companies customer base). Suppose a random sample of 64 purchasers of this table saw is taken. Question 19 Not yet answered Marked out of 1.00 Question text What is the probability that the sample mean will be more than 46 minutes Answer ? Answer should be to four decimal places which is consistent with the number of decimal places listed in your appendix tables e.g. 0.1234 etc. Please do NOT include any units in your answer. Question 20 Not yet answered Marked out of 1.00 Question text A quality control engineer is interested in the mean length of sheet insulation being cut automatically by machine. The desired length of the insulation is 12 metres. It is known that the standard deviation in the cutting length is 0.15 metres. A sample of 144 cut sheets yield a mean length of 12.14 metres. This sample will be used to obtain a 90% confidence interval for the mean length cut by machine. What are the two limits of the confidence interval? min = Answer max = Answer Answer should be to four decimal places e.g. 1.2345 and 2.3456. Please do NOT include any units in your answer. Information Information text An insurance company wishes to examine the relationship between income (in $,000) and the amount of life insurance (in $,000) held by families. The company drew a simple random sample of families and obtained the following results: Family Income Amount of life insurance A 40 110 B 80 200 C 110 220 D 80 150 E 80 170 F 120 270 G 60 140 H 100 240 I 60 150 J 90 200 Question 21 Not yet answered Marked out of 1.00 Question text What is the least squares estimate of the slope? Answer should be to four decimal places e.g. 1.2345. Please do NOT include any units in your answer. Answer: Question 22 Not yet answered Marked out of 1.00 Question text What is the least squares estimate of the Y intercept? Answer should be to four decimal places e.g. 1.2345. Please do NOT include any units in your answer. Answer: Question 23 Not yet answered Marked out of 1.00 Question text What is the prediction for the amount of life insurance for a family whose income is $85,000? Answer should be to four decimal places and be consistent with your original data set, e.g. if your answer was $75,410.90, you would enter 75.4109 as your answer. Please do NOT include any units in your answer. Answer: Question 24 Not yet answered Marked out of 1.00 Question text What would be the residual (error) term for a family income of $90,000? Answer should be to four decimal places and be consistent with your original data set e.g. if your answer was $940.90, you would enter 0.9409. If your answer was $9,400.90, you would enter 9.4009 etc. Please do NOT include any units in your answer. Answer: Information Information text International Pictures is trying to decide how to distribute its new movie 'Claws'. 'Claws' is the story of an animal husbandry experiment at the University of Southern Queensland that goes astray, with tragic results. An effort to breed meatier chickens somehow produces an intelligent, 200 kilogram chicken that escapes from the lab and terrorises the campus. In a surprise ending the chicken is befriended by coach Tim Galvano, who teaches it how to play Rugby and help his team win State, National and World Championships. Because of the movie's controversial nature, it has the potential to be either a smash hit, a modest success, or a total bomb. International is trying to decide whether to release the picture for general distribution initially or to start out with a 'limited first-run release' at a few selected theatres, followed by general distribution after 3 months. The company has estimated the following probabilities and conditional profits for 'Claws': PROFITS (Millions of $) Level of success Probability Limited release General distribution Smash .3 22 12 Modest .4 9 8 Bomb .3 -10 -2 International can run sneak previews of 'Claws' to get a better idea of the movies' ultimate level of success. Preview audiences rate movies as either good or excellent. On the basis of past experiences, it was found that 90% of all smash successes were rated excellent (and 10% rated good), 75% of all modest successes were rated excellent (25% rated good) and 40% of all bombs were rated excellent (60% rated good). The cost of running sneak previews is not cheap. Currently, this stands at $1m. Question 25 Not yet answered Marked out of 1.00 Question text What is the opportunity loss for a General Distribution for a Modest level of success? Answer should be to whole numbers only. You do not need to put any units in your answer. Answer: Question 26 Not yet answered Marked out of 1.00 Question text What would the optimal action be for International before running the sneak preview? Select one: Run a limited release with an expected payoff of $7.20m Run a limited release with an expected payoff of $6.20m Run a general distribution with an expected payoff of $7.20m Run a general distribution with an expected payoff of $6.20m Question 27 Not yet answered Marked out of 1.00 Question text What is the maximum amount of money that International would be prepared to pay for an absolutely reliable forecast of the movies' level of success? Select one: $9.6m $7.2m $6.2m $2.4m Question 28 Not yet answered Marked out of 1.00 Question text What would be the joint probability for a 'modest success' and excellent preview given that in the past, it was found that 75% of all modest successes were rated excellent? Answer should be to two decimal places e.g. 0.12, 0.23, etc. Please do NOT include any units in your answer. Answer: Question 29 Not yet answered Marked out of 1.00 Question text What is the posterior probability of a smash success given the sneak preview indicates good? Answer should be to four decimal places e.g. 0.1234, 0.2345 etc. Please do NOT include any units in your answer. Answer: Information Information text The tourist industry is subject to enormous seasonal variation. A hotel in North Queensland has recorded its occupancy rate for each quarter during the past 5 years. These data are shown in the accompanying table. Table 1: Occupancy rate Year 2004 2005 2006 2007 2008 Quarter 1 0.561 0.575 0.594 0.622 0.665 Quarter 2 0.702 0.738 0.738 0.708 0.835 Quarter 3 0.800 0.868 0.729 0.806 0.873 Quarter 4 0.568 0.605 0.600 0.632 0.670 Question 30 Not yet answered Marked out of 1.00 Question text (All calculations should be to at least three decimal places) What is the centred moving average that would correspond to Quarter 1 in 2006? Answer should be consistent with the data provided and be to three decimal places e.g. 0.123, 0.456 etc. Please do NOT include any units in your answer. Answer: Question 31 Not yet answered Marked out of 1.00 Question text (All calculations should be to at least three decimal places) What is the adjusted seasonal index for Quarter 1 Answer %? Answer should be listed to three decimal places in the form 0.123 i.e. 0.123 represents 12.3%, 1.234 represents 123.4% etc. Please do NOT include the units (%) in your answer. Question 32 Not yet answered Marked out of 1.00 Question text (All calculations should be to at least three decimal places) The trend line for this decomposition model can be read off the following partial regression printout (at 3 decimal places) to be Y = 0.650 + 0.004 T where T represents time. Analysing the partial regression printout, what is the coefficient of determination (R2) for this trend line? (Select the closest correct answer). Select one: 0.0932 (9.32%) 0.3448 (34.48%) 0.4545 (45.45%) 0.5455 (54.55%) Question 33 Not yet answered Marked out of 1.00 Question text (All calculations should be to at least three decimal places) What would be the forecast in Quarter 1, 2009 using the trend line previously given (i.e. Y = 0.650 + 0.004 T) and the relevant adjusted seasonal index? Answer should be consistent with the data provided and be to three decimal places e.g. 0.123, 0.456 etc. Please do NOT include any units in your answer. Answer: Question 34 Not yet answered Marked out of 1.00 Question text (All calculations should be to at least three decimal places) If we exponentially smooth the data in Table 1 with a smoothing constant of 0.1, the smoothed value for Quarter 4 in 2004 would be? Answer should be consistent with the data provided and be to three decimal places e.g. 0.123, 0.456 etc. Please do NOT include any units in your answer. Answer: Question 35 Not yet answered Marked out of 1.00 Question text (All calculations should be to at least three decimal places) If we exponentially smooth the data in Table 1 with a smoothing constant of 0.1, the forecast for Quarter 1 2009 would be? Answer should be consistent with the data provided and be to three decimal places e.g. 0.123, 0.456 etc. Please do NOT include any units in your answer. Answer: Sidebar Skip USQ Course Navigation USQ Course Navigation