RES 342 Final Exam Click here for the Answers1) What are the critical z-values for a two-tailed hypothesis test if the significant level = 0.01?A. ± 1.96B. ± 2.33C. ± 2.58D. ± 1.652) In classical hypothesis testing, the test statistic is to the critical value what the __________.A. ‘p-value’ is to alphaB. critical value is to alphaC. test statistic is to the ‘p-value’D. level of significance is to the test statistic3) For a hypothesis test of a single population mean at 95% confidence level, a calculated Zscore of 1.7 supports the conclusion thatA. the population mean is greater than the hypothesized valueB. the null hypothesis cannot be rejectedC. the sample is biasedD. the population mean is less than expected
4) If the paired differences are normal in a test of mean differences, then the distribution used fortesting is theA. normal distributionB. chi-squareC. student distributionD. F distribution5) One hundred women were polled and 60 reported successfully communicating an automobileproblem to an auto repairman. A sample of 150 men had 95 reporting the same success. Thevalue of the test statistic for a test of the equality of proportions isA. -0.5319B. 0.7293C. -0.419D. 0.27026) Weekly sales of iPods® at 20 Best Buy® stores are compared before and after installing anew eye-catching display. To determine if the display is effective in increasing sales, what typeof statistical test would you perform?A. Comparison of means using independent samples using a t-testB. Comparison of proportions using independent samples using a z-testC. Comparison of means using a paired z-testD. Comparison of means using a paired t-test7) When is it appropriate to use the paired difference t-test?A. Four samples are compared at once.B. Any two samples are compared.
C. Two independent samples are compared.D. Two dependent samples are compared.8) A survey of hotels found that the average hotel room rate in New Orleans is $88.42 and theaverage room rate in Phoenix is $80.61. The survey sampled 50 hotels in each city. The standarddeviations were $5.62 and $4.83, respectively. At alpha=.05, it can be concluded that there is asignificant different in the rates?A. 7.45B. -1.96C. 1.96D. -7.459) If the paired differences are normal in a test of mean differences, the distribution used fortesting is theA. normal distributionB. chi-squareC. student distributionD. F distribution10) The accountant for Thomas’s Furniture Store is concerned regarding the outstandingreceivable owed the company. There has been a cash flow problem and it is believed that theslow collection of accounts receivable is partially the blame. The accountant believes that 40%of the present accounts are more than 4 months behind in making payments. To be able to makea decision regarding this belief, a random sample of 100 accounts was taken. It was found that 37accounts were more than 4 months late. Did the sample data confirm the accountant’s belief?Use the .05 significant level for the statistical test.A. There is not enough evidence to confirm or deny the belief.B. The accountants belief is not confirmed.
C. The accountants belief is confirmed.D. The accountant needed to take a larger sample.11) New college business graduates are finding it difficult to get a job. A business journal hasreported that only one in five graduates is able to find a job within 6 months of their graduation.A report by University of Phoenix indicated that out of a survey of 300 recent businessgraduates, 75 had jobs. You are a business major at University of Phoenix and have a concernabout getting a job. Based on this data, will a graduate of University of Phoenix have a betterchance of getting a job in the first 6 months after graduation? Use the .05 significant level for thetest.A. No, there is not a significant difference.B. It cannot be predicted based on this data.C. Yes, there is a significant difference.D. The business journal information is incorrect.12) Analysis of variance (ANOVA) is used toA. compare nominal dataB. compute t- testC. compare population proportionD. simultaneously compare several population means13) Mr. Thomas owns three different restaurants in Cincinnati, Ohio. He is concerned about theprofitability of the restaurants. There are monthly differences between the restaurants and hewants to determine if the differences in profit are significant. Mr. Thomas wants to do astatistical test to see if he should be concerned. The best test to address this problem would beA. a paired t- testB. two different t testsC. an ANOVA test
D. a two sample test14) Sound engineers studied factors that might affect the output, in decibels, of a rock concert’sspeaker system. The desired level of significance was a = .05. The results of their ANOVA testsare shown:Source of Variation SS df MS F P-valueAmplifier 99.02344 99.02344 0.005718Position 93.98698 31.32899 3.215807 0.051003Interaction 10.15365 3 3.384549 0.347412 0.791505Error 155.875 16 9.742188Total 359.0391 23The interaction between the Position and Amplifier treatments wasA. very significantB. slightly significantC. insignificantD. highly correlated15) Totto, an automobile manufacturer, has designed a radically new engine and wants torecommend the grade of gasoline that will have the best fuel economy. The four grades areregular, below regular, premium, and super premium. The test car made three trial runs on thetest track using each of the grades and the miles per gallon were recorded. At the 0.05 level, whatis the critical value of F used to test the hypothesis that the miles per gallon for each fuel are thesame?A. 1.96B. 4.07C. 2.33D. 12.00
16) If an ANOVA test is conducted and the null hypothesis is rejected, what does this indicate?A. Too many degrees of freedomB. A difference between at least one pair of population meansC. No difference between the population meansD. The variances are the same17) Nonparametric statistics are used whenA. you have qualitative data, with your variables being measured at the nominal or interval levelB. you have qualitative data, with your variables being measured at the ordinal or ratio levelC. you have qualitative data, with your variables being measured at the nominal or ordinal levelD. you have qualitative data, with your variables being measured at the ordinal or interval level18) The nonparametric test most commonly used for testing the statistical independence betweentwo variables isA. the Kruskal- Wallis testB. the Chi- Square testC. the Mann Whitney testD. the Sign test19) What nonparametric test is used when the assumptions for the parametric ANOVA cannot bemet? Its purpose is to test whether three or more populations are equal. The data must be at leastordinal scaled.A. Students’ tB. Kruskal- Wallis
C. Mann-WhitneyD. ANOVA20) Rachael Smith is the personnel manager at Johnson and Johnston, an accounting firm. She isconcerned about absenteeism, which seems to be an increasing problem, especially after days offwork. She decided to sample the records to determine if absenteeism was distributed evenlythroughout the 6-day work week. The null hypothesis to be tested was: Absenteeism isdistributed evenly throughout the week. The sample results were:Day of Week Number AbsentMonday 12Tuesday 9Wednesday 11Thursday 10Friday 9Saturday 9What is the critical value of chi-square with a significant level of = 0.05?A. 11.070B. 12.592C. 13.388D. 15.03321) A public opinion poll surveyed a simple random sample of voters. Respondents wereclassified by gender and by voting preference—Republican, Democrat, or Independent. Theresults follow.Voting Preferences Republican Democrat Independent Row totalMale 200 150 50 400
Female 250 300 50 600Column total 450 450 100 1000If you conduct a chi-square test of independence, what is the expected frequency count of maleIndependents?A. 50B. 60C. 40D. 3022) What parametric test is equivalent to the nonparametric Spearmans rank test?A. T-test of correlation coefficientB. T-test of two sample meansC. T-test of one sample mean.D. T-test of two sample proportions23) What is the variable used to predict another variable called?A. Independent variableB. Dependent variableC. Moderating variableD. Intervening variable24) Michelle used a sample of 50 U.S. cities to estimate the relationship between crime, orannual property crimes per 100,000 persons, and income, or median income per capita. Herestimated regression equation was crime = 428 - .01 income. Assuming her model is statisticallysignificant, if income decreases by $1,000, we would predict that crime will
A. decrease by 1B. increase by 10C. decrease by 10D. increase by 100RES 342 Final Exam25) In the least squares equation, Y = 12 + 25X the value of 25 indicatesA. the y- interceptB. for each unit increase in x, y increases by 25C. for each unit increase in y, x increases by 25D. the residual of x factor26) A test is conducted in eight cities to see if giving away free transit system maps will increasebus ridership. In a regression analysis, the dependent variable is the increase in bus ridership inthousands of persons from the start of the test until its conclusion. The independent variables areX1 = the number in thousands of free maps distributed and X2 = a binary equal to 1, if the cityhas free downtown parking and 0 otherwise. The estimated regression equation is Y =1.32+.0345X1-1.45X2. If the Y value for city 3 is 7.3, X1 = 140, and X2 = 0 the residual for city3 in thousands is:A. 6.34B. 1.15C. .57D. 2.01RES342 Final Exam27) The following linear trend equation was developed for the annual sales of the TractorManufacturing Company. Y = 355 + 50t in thousands of dollars. How much are sales increasingby?A. $50,000 per year
B. $5,00 per monthC. $500,000 per yearD. $6,000 per year28) The time series component that reflects variability over short, repetitive time periods that lastless than one year is calledA. long-term trendB. cyclical variationC. seasonal variationD. irregular variation29) A research company has been hired by a realty company to do an analysis of heating cost ofhomes in the region. The realty company wanted to be able to predict the heating cost of atypical single-family home. The realty company was constantly being asked questions regardingheating costs by potential home buyers. It was believed that these variables would impact heatingcosts (Y): mean daily outdoor temperature (X1), the number of inches of insulation (X2), andthe age in years of the furnace (X3). The multiple regression analysis produced the followingregression equation: Y = 427.2 – 4.58X1 – 14.83X2 + 6.10X3. Which statement is correct basedon this analysis?A. The age of the furnace has an indirect relationship with heating costs.B. There is an inverse relationship between outdoor temperature and heating costs.C. There is no real clear relationship between these variables.D. There exists a direct relationship between inches of insulation and heating costs.30) If we fit a linear trend to data that are growing exponentially,A. the fitted trend will be too high at the endB. the forecasts, if extrapolated, will be too low
C. the forecasts, if extrapolated, will be too highD. the fitted trend will be too low in the middle