Bluman A.G. Elementary Statistics- A Step By Step Approach

714 Chapter 13 Nonparametric StatisticsChapter QuizDetermine whether each statement is true or false. If thestatement is false, explain why.1. Nonparametric statistics cannot be used to test thedifference between two means. False2. Nonparametric statistics are more sensitive than theirparametric counterparts. False3. Nonparametric statistics can be used to test hypothesesabout parameters other than means, proportions, andstandard deviations. True4. Parametric tests are preferred over their nonparametriccounterparts, if the assumptions can be met. TrueSelect the best answer.5. The test is used to test means when samplesare dependent and the normality assumption cannot bemet.a. Wilcoxon signed-rank c. Signb. Wilcoxon rank sum d. Kruskal-Wallis6. The Kruskal-Wallis test uses the distribution.a. z c. Chi-squareb. t d. F7. The nonparametric counterpart of ANOVA is the.a. Wilcoxon signed-rank testb. Sign testc. Runs testd. None of the above8. To see if two rankings are related, you can use the.a. Runs testb. Spearman correlation coefficientc. Sign testd. Kruskal-Wallis testComplete the following statements with the best answer.9. When the assumption of normality cannot be met, youcan use tests. Nonparametric10. When data are or in nature,nonparametric methods are used. Nominal, ordinal11. To test to see whether a median was equal to a specificvalue, you would use the test. Sign12. Nonparametric tests are less than theirparametric counterparts. SensitiveFor the following exercises, use the traditional method ofhypothesis testing unless otherwise specified.13. Home Prices The median price for an existinghome in 2009 was $177,500. A random sample ofhomes for sale listed by a local realtor indicated homesavailable for the following prices. Test the claim that themedian is not $177,500. Use a 0.05.184,500 174,900 155,000 210,000 235,500 399,900355,900 182,500 229,900 199,900 169,900 219,900Source: World Almanac.14. Lifetimes of Batteries A battery manufacturer claimsthat the median lifetime of a certain brand of heavy-dutybattery is 1200 hours. A sample of 25 batteries showsthat 15 lasted longer than 1200 hours. Test the claim ata 0.05. Use the sign test.15. Weights of Turkeys A special diet is fed to adultturkeys to see if they will gain weight. The before andafter weights (in pounds) are given here. Use the pairedsamplesign test at a 0.05 to see if there is weightgain.Before 28 24 29 30 32 33 25 26 28After 30 29 31 32 32 35 29 25 3116. Charity Donations Two teams of 10 memberseach solicited donations for their participation in acharity walk for blood cancer research. The teamsreceived the following amounts. At a 0.05 can it beconcluded that there is a difference in amounts?Team A 100 50 65 50 60 75 100 150 108 120Team B 135 90 80 140 155 60 200 58 70 7217. Textbook Costs Samples of students majoring inlaw and nursing are selected, and the amount eachspent on textbooks for the spring semester is recordedhere, in dollars. Using the Wilcoxon rank sum test ata 0.10, is there a difference in the amount spent byeach group?Law 167 158 162 106 98 206 112 121Nursing 98 198 209 168 157 126 104 122Law 133 145 151 199Nursing 111 138 116 20118. Student Grade Point Averages The grade pointaverage of a group of students was recorded for onemonth. During the next nine-week grading period, thestudents attended a workshop on study skills. TheirGPAs were recorded at the end of the grading period,and the data appear here. Using the Wilcoxon signedranktest at a 0.05, can it be concluded that the GPAincreased?Before 3.0 2.9 2.7 2.5 2.1 2.6 1.9 2.0After 3.2 3.4 2.9 2.5 3.0 3.1 2.4 2.813–44