Review-Problems

11.Theprocessofusingsamplestatisticstodrawconclusionsabouttruepopulationparametersiscalled()A.statisticalinference.B.thescientificmethod.C.sampling.D.descriptivestatistics.2.Thecollectionandsummarizationofthesocioeconomicandphysicalcharacteristicsoftheemployeesofaparticularfirmisanexampleof()A.inferentialstatistics.B.descriptivestatistics.C.aparameter.D.astatistic.3.Theuniverseortotalityofitemsorthingsunderconsiderationiscalled()A.asample.B.apopulation.C.aparameter.D.astatistic.4.Whichofthefollowingstatisticsisnotameasureofcentraltendency?()A.Arithmeticmean.B.Median.C.Mode.D.Q3.5.WhichoneofthefollowingisNOTanexampleofdiscretedata?()A.NumberofhouseholdswatchingtheHomeShoppingNetwork.B.Numberofemployeesreportinginsick.C.NumberofmilesbetweenNewYorkCityandChicago.D.NumberofmembersoftheDenverLionsClub.6.Inaright-skeweddistribution()A.themedianequalsthearithmeticmean.B.themedianislessthanthearithmeticmean.C.themedianislargerthanthearithmeticmean.D.noneoftheabove.7.Thecoefficientofvariationforasetofannualincomesis18%;thecoefficientofvariationforthelengthofservicewiththecompanyis29%.Whatdoesthisindicate?()A.MoredispersioninthedistributionoftheincomescomparedwiththedispersionoftheirlengthofserviceB.MoredispersioninthelengthsofservicecomparedwithincomesC.Dispersioninthetwodistributions(incomeandservice)cannotbecomparedusingpercentsD.Dispersionsareequal28.Selectthemeasureofcentrallocationwiththefollowingcharacteristic:thesumofthedeviationsofeachvaluefromthemeanwillalwaysbezero.()A.ModeB.MeanC.MedianD.Geometricmean9.Initsstandardizedform,thenormaldistribution()A.hasameanof0andastandarddeviationof1.B.hasameanof1andavarianceof0.C.hasanareaequalto0.5.D.mayhavetwomodes.10.TheCentralLimitTheoremstatesthatforlargesamples,thesamplemeanXwillhave()A.anexactnormaldistributionB.atdistributionwhenthepopulationstandarddeviationisunknownC.anapproximatenormaldistributionD.astandardnormaldistribution.11.Theeveninghostofadinnerdancereachedintoabowl,mixedalltheticketsaround,andselectedthetickettoawardthegranddoorprize.Whatsamplingmethodwasused()A.SimplerandomsampleB.SystematicsampleC.StratifiedsampleD.Clustersample12.WhichofthefollowingisNOTnecessarytodeterminehowlargeasampletoselectfromapopulation?()A.LevelofconfidenceinestimatingthepopulationparameterB.SizeofthepopulationC.MaximumallowableerrorinestimatingthepopulationparameterD.Estimateofthepopulationvariation13.Aconfidenceinterval()A.Alwaysincludesthepopulationparameter.B.Decreasesinwidthasthesamplesizeisincreased.C.Cannotincludeavalueof0.D.Noneoftheabove.14.ATypeIIerroroccurswhen()A.Wedonotrejectafalsenullhypothesis.B.Werejectatruenullhypothesis.C.Werejectafalsenullhypothesis.D.Noneoftheabove.315.Ifahypothesisisnotrejectedatthe0.01and0.05levelofsignificance,butrejectedatthe0.10level,then()A.p-value0.01B.p-value0.10C.0.01p-value0.05D.0.05p-value0.10.16.Inregressionanalysis,theresidualsrepresentthe()A.differencebetweentheactualxvaluesandtheirpredictedvaluesB.differencebetweentheactualyvaluesandtheirpredictedvaluesC.squarerootofthecoefficientofdeterminationD.changeinyperunitchangeinx.TABLE2-1Aninsurancecompanyevaluatesmanynumericalvariablesaboutapersonbeforedecidingonanappropriaterateforautomobileinsurance.Arepresentativefromalocalinsuranceagencyselectedarandomsampleofinsureddriversandrecorded,X,thenumberofclaimseachmadeinthelast3years,withthefollowingresults.Xf114218312455117.ReferringtoTable2-1,howmanydriversarerepresentedinthesample?a)5b)15c)18d)50ANSWER:dKEYWORDS:frequencydistribution18.ReferringtoTable2-1,howmanytotalclaimsarerepresentedinthesample?a)15b)50c)111d)250ANSWER:cKEYWORDS:interpretation,frequencydistribution4TABLE9-4Adrugcompanyisconsideringmarketinganewlocalanesthetic.Theeffectivetimeoftheanestheticthedrugcompanyiscurrentlyproducinghasanormaldistributionwithanaverageof7.4minuteswithastandarddeviationof1.2minutes.Thechemistryofthenewanestheticissuchthattheeffectivetimeshouldbenormalwiththesamestandarddeviation,butthemeaneffectivetimemaybelower.Ifitislower,thedrugcompanywillmarketthenewanesthetic;otherwise,theywillcontinuetoproducetheolderone.Asampleofsize36resultsinasamplemeanof7.1.Ahypothesistestwillbedonetohelpmakethedecision.1.ReferringtoTable9-4,theappropriatehypothesesare:a)4.7:versus4.7:10HHb)4.7:versus4.7:10HHc)4.7:versus4.7:10HHd)4.7:versus4.7:10HHANSWER:cKEYWORDS:one-tailedtest,mean,Ztest,formofhypothesis,formofhypothesis2.ReferringtoTable9-4,foratestwithalevelofsignificanceof0.10,thecriticalvaluewouldbe________.ANSWER:-1.28KEYWORDS:one-tailedtest,mean,Ztest,criticalvalue3.ReferringtoTable9-4,thevalueoftheteststatisticis________.ANSWER:-1.50KEYWORDS:one-tailedtest,mean,Ztest,teststatistic4.ReferringtoTable9-4,thep-valueofthetestis________.ANSWER:0.0668KEYWORDS:one-tailedtest,mean,Ztest,p-value5.TrueorFalse:ReferringtoTable9-4,thenullhypothesiswillberejectedwithalevelofsignificanceof0.10.ANSWER:TrueKEYWORDS:one-tailedtest,mean,Ztest,decision6.TrueorFalse:ReferringtoTable9-4,ifthelevelofsignificancehadbeenchosenas0.05,thenullhypothesiswould