Final Exam - Results Attempt 1 of 1 Written Apr 2, 2024 1:31 PM - Apr 2, 2024 3:39 PM Released Apr 3, 2024 12:00 PM Attempt Score 94.67 / 100 - 94.67 % Overall Grade (Highest Attempt) 94.67 / 100 - 94.67 % What is a Confidence Interval Question 1 3 / 3 points With 95% confidence, the program director estimated that the proportion of MGMT650 students that are very satisfied is 90% ± 5%. It's in the top 10% of all classes. What is a Confidence Interval The proportion of very satisfied students cannot be off by more than 5%. With 95% probability, the true proportion of very satisfied students falls between 85% and 95%. Loosely, we say with 95% confidence that the true proportion is somewhere between 85% and 95%. Actually, 95% of all possible confidence intervals contain the true proportion. There is a 5% probability that the true proportion of very satisfied students falls between 85% and 95%.

Question 2 3 / 3 points Answer: 0.54 Hide ques²on 2 feedback Margin of Error - Mean Question 3 4 / 4 points What is the margin of error for the population mean at 90% confidence level for the information in DATA (<--- Click the link to access the data for this problem.) With 80% confidence, for sample proportion 0.42 and sample size 28, what is the upper confidence limit with 2 decimal places? With 80% confidence, for sample proportion p and sample size n, the upper confidence limit is p + NORM.S.INV(1 - (1 - 0.80)/2) x SQRT( p(1-p)/n ) Margin Mean 0.72 0.76 None of the answers match my calculation. 0.75 0.74 0.73 0.71

Question 6 3 / 3 points Match up the following: __ 4__ __ 1__ __ 3__ __ 2__ 1 . 2 . 3 . 4 . Question 7 4 / 4 points Match up the following: __ 2__ __ 1__ 1 . 2 . 3 . 4 . None of the answers match my calculation. The confidence limits (2.77, 4.54) reject the claim of 5 minutes. 5 is greater than the upper confidence limit. Bobo's performance is exemplary. The confidence limits (6.79,8.56) reject the claim of 5 minutes. 5 is less than the lower confidence limit. Audit of Bobo's procedures and employees is recommended. The confidence limits (1.62,3.21) reject the claim of 5 minutes. 5 is greater than the upper confidence limit. Performance at Bobo's is incredible. The risk we are willing to take of a type 1 error, or the type 1 error rate Rejection of H0 when H0 is true Rejection of H0 when H0 is false, or not rejecting H0 when H0 is true Failure to reject H0 when H0 is false Type 1 error Type 2 error Not an error The power of a test = P(rejecting H 0 |H 0 false) The probability of a type 2 error 1 - pvalue < H 0 : μ ≤ 0

__ 4__ __ 6__ __ 5__ __ 3__ 5 . 6 . Question 8 3 / 3 points Match the rules for rejecting H0 at the right to the following tests __ 3__ __ 2__ __ 4__ __ 1__ 1 . 2 . 3 . 4 . Question 9 3 / 3 points Match problems to procedures. Test of this hypothesis requires 1-tailed test with upper reject region Test of this hypothesis requires 2-tailed test with lower reject region bounded by negative critical value and upper reject region bounded by positive critical value Test of this hypothesis requires 1-tailed test with lower reject region bounded by negative critical value Reject H 0 H 0 : μ ≥ 0 H 0 : μ = 0 Two-tail test with lower and upper reject regions One-tail test with lower reject region For any test hypothesis, ANOVA, or Chi Squared, this rule for rejecting H0 always applies. One-tail test with upper reject region test statistic > positive critical value test statistic < negative critical value test statistic outside interval (negative critical value, positive critical value) pvalue <

__ 3__ __ 4__ Question 10 3 / 3 points Match problems to procedures. __ 3__ __ 1__ 1 . 2 . 3 . 4 . at = 0.05 test that the population mean is 35. Test size C battery mean life is at least 25 hours. To test that a gasoline additive increases mileage, we compute mpg with additive minus mpg without additive for each car. If the mean of the differences is positive enough, action will be required to implement the additive. Do 2-way table classification labels matter? Data were gathered in an experiment comparing the effects of three insecticides in controlling a certain species of parasitic beetle. Each observation represents the number of such insects found dead in a certain fixed area treated with an insecticide. ANOVA Chi-square test of homogeneity Chi-square test of independence Chi-square test of goodness of fit

__ 2__ __ 4__ Test H0 - Proportion Question 11 4 / 4 points An Air Quality instrument logs 0 when standards are not met and 1 when standards are met. The log is saved to file DATA. First, compute the proportion meeting standards as the mean of Air Quality values. Second, at alpha = 0.10 (sensitive, exploratory), test the hypothesis that proportion of times that air quality meets standards is at least 90%. A multinomial probability distribution describes the distribution of counts across multiple levels of a variable. For each level of a variable, which is common to multiple populations, are the distributions the same. Does the data validate the normal probability distribution assumption? Proportion None of the answers match my calculation. The pvalue of 0.062 indicates that the data provide weak evidence against H0: π ≥ 0.90. H0 is rejected at = 0.10. The pvalue of 0.006 indicates that the data provide overwhelming evidence against H0: π ≥ 0.90. H0 is rejected at = 0.10. Send out an air quality alert. The pvalue of 0.022 indicates that the data provide strong evidence against H0: π ≥ 0.90. H0 is rejected at = 0.10. The status quo has changed.

Hide ques²on 12 feedback Test H0 - Paired Data Question 13 4 / 4 points The Fast N' Hot food chain wants to test if their "Buy One, Get One Free" program increases customer traffic enough to support the cost of the program. For each of 15 stores, one day is selected at random to record customer traffic with the program in effect, and one day is selected at random to record customer traffic with program not in effect. The results of the experiment are documented in DATA. For each store, compute difference = traffic with program minus traffic without program. At = 0.05, test the hypothesis that the mean difference is at most 0 (at best the program makes no difference, or worse it decreases traffic) against the alternative that the mean difference > 0 (the program increases traffic). The test statistic of 1.908 is greater than the critical value of 1.734, therefore H0 is rejected. It is reasonable to assume that the distance is not 295 yards. None of the answers match my calculation. Detailed feedback available upon request. Test H0 - Paired The pvalue of 0.221 indicates that the data provide insignificant evidence against H0. H0 is not rejected at = 0.05. You decide to conclude the study and not to recommend the program. The pvalue of 0.033 provides strong evidence against H0. H0 is rejected at = 0.05. You decide to recommend further evaluation of the program. None of the answers match my calculation. The pvalue of 0.002 provides overwhelming evidence against H0. H0 is rejected at = 0.05. You decide that the program results in increased

Hide ques²on 13 feedback Test H0 - 2 Means Question 14 4 / 4 points BigDeal Real Estate surveyed prices per square foot in the valley and foothills of Hoke-a-mo, Utah. Based on BD's DATA, are prices per square foot equal at = 0.01 ? customer traffic, overall, and recommend the program be implemented. The pvalue rejects H0: Mean difference > 0. The pvalue of 0.084 provides weak evidence against H0. H0 is not rejected at = 0.05. You decide the evidence is not strong enough to recommend further evaluation of the program. Detailed feedback available upon request. Test H0 2Means The critical value is 2.977 since this is a two-tail scenario. The test statistic is 1.936. Since the test statistic < the critical value, the test statistic does not lie in the area of rejection. Do not reject the null hypothesis. The prices per square foot are equal at alpha = .01 The critical value is 2.977 since this is a two-tail scenario. The test statistic is 1.513. Since the test statistic < the critical value, the test statistic does not lie in the area of rejection. Do not reject the null hypothesis. The prices per square foot are equal at alpha = .01 The critical value is 2.977 since this is a two-tail scenario. The test statistic is 2.239. Since the test statistic < the critical value, the test statistic does not lie in the area of rejection. Do not reject the null hypothesis. The prices per square foot are equal at alpha = .01 The critical value is 2.977 since this is a two-tail scenario. The test statistic is 3.207. Since the test statistic > the critical value, the test

Hide ques²on 15 feedback ANOVA - 2 Question 16 4 / 4 points To test whether the mean time to mix a batch of adhesive is the same for machines produced by four manufacturers, TiteBondMax obtained DATA on the time (minutes) needed to mix the materials. Test whether the machines have equal mean mixing time at = 0.05. Hide ques²on 16 feedback Pivot Table Detailed feedback available upon request. ANOVA - 2 The data provide strong evidence against H0: Equal means at pvalue 0.013. The mixing machines are not all equal. The data provide extreme evidence against H0: Equal means at pvalue 0.001. The mixing machines are not all equal. None of the answers match my calculation. The data provide weak evidence against H0: Equal means at pvalue 0.072. Equality of means remains plausible. The pvalue 0.0001 is extreme evidence that the machines are not all the same. The data provide insignificant evidence against H0: Equal means at pvalue 0.514. The machine are considered equal. Detailed feedback available upon request. Pivot Table

Question 17 4 / 4 points To balance inventory at Otto's Optometry, customer Gender and Eye Condition were collected in DATA. Make a 2x2 pivot table with Gender in rows and Eye Condition in columns. The pivot table is Question 18 3 / 3 points Answer: 7.6 None of the answers match my table Given the following contingency table with category labels A, B, C, X, Y, and Z, what is the expected count with 1 decimal place in the joint category of C and X? X Y Z A 6 10 10 B 15 6 2 C 10 1 5

Hide ques²on 20 feedback ChiSquare - Goodness of Fit Question 21 4 / 4 points A sales region has been divided into five territories, each of which was believed to have equal sales potential. The actual Sales Volume for several sampled days is logged in DATA. At = 0.05, do the territories have equal Sales Volume? Pvalue of 0.008 rejects the assumption of independence of Part Quality and Supplier. Further supplier evaluation is recommended. The assumption of independence of Part Quality and Supplier cannot be rejected. Choose the cheapest Supplier. None of the answers match my calculation. Pvalue of 0.0008 rejects the assumption of independence of Part Quality and Supplier. Further supplier evaluation is recommended. Detailed feedback available upon request. ChiSquare - Goodness of Fit None of the answers match my calculation. H0: Territories have equal Sales Volume is rejected with pvalue 0.041. The counts are not consistent with the model of equal proportions. Territories have unequal Sales Volume. H0: Territories have equal Sales Volume is not rejected with pvalue 0.334. The counts are consistent with the model of equal proportions. H0: Territories have equal Sales Volume is rejected with pvalue 0.012. The counts are not consistent with the model of equal proportions. Territories have unequal Sales Volume. H0: Territories have equal Sales Volume is not rejected with pvalue 0.074. The counts are consistent with the model of equal proportions.

Hide ques²on 21 feedback Correlation - Qualitative Assessment Question 22 4 / 4 points Scatter plots are used to discover relationships between variables. Using the corresponding measurements of variable1 and variable2 in DATA, plot variable1 vs. variable2 and describe the correlation between variable1 and variable2. Hide ques²on 22 feedback Correlation - Quantitative Evaluation Question 23 4 / 4 points Detailed feedback available upon request. Correlation - Qualitative Assessment The strength of the relationship is strong, but it is not linear. None of the answers accurately characterize the data. The relationship is linear, negative, and strong. The relationship is linear, positive, and strong. The strength of the relationship is moderate, linear, and negative. The strength of the relationship is moderate, linear, and positive. There is no relationship, or the strength of the relationship is very weak Detailed feedback available upon request. Correlation - Quantitative Evaluation

5 . 6 . Regression - Assumption Question 25 0 / 4 points You are required to setup a predictive equation involving variable 1 and variable 2. First, you plot the DATA to determine if linear regression applies. You decide Hide ques²on 25 feedback Regression - Interpret slope The strength and direction of the linear relationship between X and Y. Denotes the intercept, or elevation of the regression line at X=0. Regression - Assumptions Linear regression is not applicable because the point pattern is curvilinear (has a curve). Linear regression is not applicable because it appears that there are two linear patterns indicating that the data come from two populations. Linear regression is not useful because the points have no discernible pattern. You need more information before deciding to use linear regression. The linear regression equation will be very useful because the points have a strong linear pattern. Detailed feedback available upon request. Regression - Interpretation

Question 26 4 / 4 points An important application of regression in manufacturing is the estimation of cost of production. Based on DATA from Ajax Widgets relating cost (Y) to volume (X), what is the cost per widget? Hide ques²on 26 feedback Regression - Estimation Question 27 4 / 4 points An important application of regression in manufacturing is the estimation of cost of production. Based on DATA from Ajax Widgets relating cost (Y) to volume (X), what is the cost of producing 600 widgets? Hide ques²on 27 feedback 8.75 7.38 None of the answers match my calculation. 8.21 7.54 Detailed feedback available upon request. Regression - Estimation 6954 None of the answers match my calculation. 5206 5826 6312