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精選優(yōu)質(zhì)文檔-----傾情為你奉上精選優(yōu)質(zhì)文檔-----傾情為你奉上專心---專注---專業(yè)專心---專注---專業(yè)精選優(yōu)質(zhì)文檔-----傾情為你奉上專心---專注---專業(yè)PartOne:MultipleChoices:1. Theprobabilitythatacontinuousrandomvariabletakesanyspecificvaluea.isequaltozerob.isatleast0.5c.dependsontheprobabilitydensityfunctiond.isverycloseto1.02. Anormaldistributionwithameanof0andastandarddeviationof1iscalleda.aprobabilitydensityfunctionb.anordinarynormalcurvec.astandardnormaldistributiond.noneofthesealternativesiscorrect3. AnegativevalueofZindicatesthata.thenumberofstandarddeviationsofanobservationistotherightofthemeanb.thenumberofstandarddeviationsofanobservationistotheleftofthemeanc.amistakehasbeenmadeincomputations,sinceZcannotbenegatived.thedatahasanegativemean4. Foracontinuousrandomvariablex,theprobabilitydensityfunctionf(x)representsa.theprobabilityatagivenvalueofxb.theareaunderthecurveatxc.theareaunderthecurvetotherightofxd.theheightofthefunctionatx5. Forthestandardnormalprobabilitydistribution,theareatotheleftofthemeanisa.-0.5b.0.5c.anyvaluebetween0to1d.16. Largervaluesofthestandarddeviationresultinanormalcurvethatisa.shiftedtotherightb.shiftedtotheleftc.narrowerandmorepeakedd.widerandflatter7. Acontinuousprobabilitydistributionthatisusefulindescribingthetime,orspace,betweenoccurrencesofaneventisa(n)a.normalprobabilitydistributionb.uniformprobabilitydistributionc.exponentialprobabilitydistributiond.Poissonprobabilitydistribution8. Considerabinomialprobabilityexperimentwithn=3andp=0.1.Then,theprobabilityofx=0isa.0.0000b.0.0001c.0.001d.0.7299. Acontinuousrandomvariablemayassumea.allvaluesinanintervalorcollectionofintervalsb.onlyintegervaluesinanintervalorcollectionofintervalsc.onlyfractionalvaluesinanintervalorcollectionofintervalsd.allthepositiveintegervaluesinaninterval10. Thehighestpointofanormalcurveoccursata.onestandarddeviationtotherightofthemeanb.twostandarddeviationstotherightofthemeanc.approximatelythreestandarddeviationstotherightofthemeand.themeanExhibit1Theassemblytimeforaproductisuniformlydistributedbetween6to10minutes.11. RefertoExhibit1.Theprobabilitydensityfunctionhaswhatvalueintheintervalbetween6and10?a.0.25b.4.00c.5.00d.zero12. RefertoExhibit1.Theprobabilityofassemblingtheproductbetween7to9minutesisa.zerob.0.50c.0.20d.113. RefertoExhibit1.Theprobabilityofassemblingtheproductinlessthan6minutesisa.zerob.0.50c.0.15d.114. RefertoExhibit1.Theprobabilityofassemblingtheproductin7minutesormoreisa.0.25b.0.75c.zerod.115. RefertoExhibit1.Theexpectedassemblytime(inminutes)isa.16b.2c.8d.416. RefertoExhibit1.Thestandarddeviationofassemblytime(inminutes)isapproximatelya.1.3333b.1.1547c.0.1111d.0.577317.a.alwaysequaltozerob.isthemeanofthedistributionc.cannotbenegatived.isthestandarddeviation18. Theuniform,normal,andexponentialdistributionsarea.allcontinuousprobabilitydistributionsb.alldiscreteprobabilitydistributionsc.canbeeithercontinuousordiscrete,dependingonthedatad.allthesamedistributions19. Whichofthefollowingisnotacharacteristicofthenormalprobabilitydistribution?a.Themean,median,andthemodeareequalb.Themeanofthedistributioncanbenegative,zero,orpositivec.Thedistributionissymmetricald.Thestandarddeviationmustbe120. Inastandardnormaldistribution,therangeofvaluesofzisfroma.minusinfinitytoinfinityb.-1to1c.0to1d.-3.09to3.0921. Parametersarea.numericalcharacteristicsofasampleb.numericalcharacteristicsofapopulationc.theaveragestakenfromasampled.numericalcharacteristicsofeitherasampleorapopulation22. Howmanysimplerandomsamplesofsize3canbeselectedfromapopulationofsize7?a.7b.21c.35d.34323. Apopulationconsistsof500elements.Wewanttodrawasimplerandomsampleof50elementsfromthispopulation.Onthefirstselection,theprobabilityofanelementbeingselectedisa.0.100b.0.010c.0.001d.0.00224. Thecloserthesamplemeanistothepopulationmean,a.thelargerthesamplingerrorb.thesmallerthesamplingerrorc.thesamplingerrorequals1d.Noneofthesealternativesiscorrect.25. Sincethesamplesizeisalwayssmallerthanthesizeofthepopulation,thesamplemeana.mustalwaysbesmallerthanthepopulationmeanb.mustbelargerthanthepopulationmeanc.mustbeequaltothepopulationmeand.canbesmaller,larger,orequaltothepopulationmean26. Asthesamplesizeincreases,thea.standarddeviationofthepopulationdecreasesb.populationmeanincreasesc.standarderrorofthemeandecreasesd.standarderrorofthemeanincreases27. Asimplerandomsamplefromaninfinitepopulationisasampleselectedsuchthata.eachelementisselectedindependentlyandfromthesamepopulationb.eachelementhasa0.5probabilityofbeingselectedc.eachelementhasaprobabilityofatleast0.5ofbeingselectedd.theprobabilityofbeingselectedchanges28. Inpointestimationa.datafromthepopulationisusedtoestimatethepopulationparameterb.datafromthesampleisusedtoestimatethepopulationparameterc.datafromthesampleisusedtoestimatethesamplestatisticd.themeanofthepopulationequalsthemeanofthesample29. Thesamplemeanisthepointestimatorofa.b.c.d.30. Theexpectedvalueoftherandomvariableisa.thestandarderrorb.thesamplesizec.thesizeofthepopulationd.Noneofthesealternativesiscorrect.31. Thestandarddeviationofallpossiblevaluesiscalledthea.standarderrorofproportionb.standarderrorofthemeanc.meandeviationd.centralvariation32. Wheneverthepopulationhasanormalprobabilitydistribution,thesamplingdistributionofisanormalprobabilitydistributionfora.onlylargesamplesizesb.onlysmallsamplesizesc.anysamplesized.onlysamplesofsizethirtyorgreater33. Thesamplingerroristhea.sameasthestandarderrorofthemeanb.differencebetweenthevalueofthesamplemeanandthevalueofthepopulationmeanc.errorcausedbyselectingabadsampled.standarddeviationmultipliedbythesamplesize34. Whichofthefollowingis(are)pointestimator(s)?a.b.c.sd.35. Apopulationcharacteristic,suchasapopulationmean,iscalleda.astatisticb.aparameterc.asampled.themeandeviation 36. Asinglenumericalvalueusedasanestimateofapopulationparameterisknownasa.aparameterb.apopulationparameterc.ameanestimatord.apointestimate37. Thepurposeofstatisticalinferenceistoprovideinformationaboutthea.samplebaseduponinformationcontainedinthepopulationb.populationbaseduponinformationcontainedinthesamplec.populationbaseduponinformationcontainedinthepopulationd.meanofthesamplebaseduponthemeanofthepopulation38. Thenumberofrandomsamples(withoutreplacement)ofsize3thatcanbedrawnfromapopulationofsize5isa.15b.10c.20d.12539.Forapopulationwithanydistribution,theformofthesamplingdistributionofthesamplemeanisa.sometimesnormalforallsamplesizesb.sometimesnormalforlargesamplesizesc.alwaysnormalforallsamplesizesd.alwaysnormalforlargesamplesizes40. Asimplerandomsampleof28observationswastakenfromalargepopulation.Thesamplemeanequaled50.Fiftyisaa.populationparameterb.biasedestimateofthepopulationmeanc.sampleparameterd.pointestimate

41. Whensisusedtoestimate,themarginoferroriscomputedbyusinga.normaldistributionb.tdistributionc.themeanofthesampled.themeanofthepopulation42. Fromapopulationwithavarianceof900,asampleof225itemsisselected.At95%confidence,themarginoferrorisa.15b.2c.3.92d.443. Inordertodetermineanintervalforthemeanofapopulationwithunknownstandarddeviationasampleof61itemsisselected.Themeanofthesampleisdeterminedtobe23.Thenumberofdegreesoffreedomforreadingthetvalueisa.22b.23c.60d.6144. Ifwewanttoprovidea95%confidenceintervalforthemeanofapopulation,theconfidencecoefficientisa.0.485b.1.96c.0.95d.1.64545. Asthenumberofdegreesoffreedomforatdistributionincreases,thedifferencebetweenthetdistributionandthestandardnormaldistributiona.becomeslargerb.becomessmallerc.staysthesamed.Noneofthesealternativesiscorrect.46. Fortheintervalestimationofwhenisknownandthesampleislarge,theproperdistributiontouseisa.thenormaldistributionb.thetdistributionwithndegreesoffreedomc.thetdistributionwithn+1degreesoffreedomd.thetdistributionwithn+2degreesoffreedom47. Anestimateofapopulationparameterthatprovidesanintervalofvaluesbelievedtocontainthevalueoftheparameterisknownasthea.confidenceervalestimatec.parametervalued.populationestimate48. Thevalueaddedandsubtractedfromapointestimateinordertodevelopanintervalestimateofthepopulationparameterisknownasthea.confidencelevelb.marginoferrorc.parameterervalestimate49. Ifanintervalestimateissaidtobeconstructedatthe90%confidencelevel,theconfidencecoefficientwouldbea.0.1b.0.95c.0.9d.0.0550. Wheneverthepopulationstandarddeviationisunknownandthepopulationhasanormalornear-normaldistribution,whichdistributionisusedindevelopinganintervalestimation?a.standarddistributionb.zdistributionc.alphadistributiond.tdistribution51. Inintervalestimation,thetdistributionisapplicableonlywhena.thepopulationhasameanoflessthan30b.thesamplestandarddeviationisusedtoestimatethepopulationstandarddeviationc.thevarianceofthepopulationisknownd.thestandarddeviationofthepopulationisknown52. Indevelopinganintervalestimate,ifthepopulationstandarddeviationisunknowna.itisimpossibletodevelopanintervalestimateb.thestandarddeviationisarrivedatusingtherangec.thesamplestandarddeviationcanbeusedd.itisassumedthatthepopulationstandarddeviationis153. Inordertousethenormaldistributionforintervalestimationofwhenisknownandthesampleisverysmall,thepopulationa.mustbeverylargeb.musthaveanormaldistributionc.canhaveanydistributiond.musthaveameanofatleast154. Fromapopulationthatisnotnormallydistributedandwhosestandarddeviationisnotknown,asampleof6itemsisselectedtodevelopanintervalestimateforthemeanofthepopulation().a.Thenormaldistributioncanbeused.b.Thetdistributionwith5degreesoffreedommustbeused.c.Thetdistributionwith6degreesoffreedommustbeused.d.Thesamplesizemustbeincreased. 55. Fromapopulationthatisnormallydistributed,asampleof25elementsisselectedandthestandarddeviationofthesampleiscomputed.Fortheintervalestimationof,theproperdistributiontouseisthea.normaldistributionb.tdistributionwith25degreesoffreedomc.tdistributionwith26degreesoffreedomd.tdistributionwith24degreesoffreedom56. Asthesamplesizeincreases,themarginoferrora.increasesb.decreasesc.staysthesamed.increasesordecreasesdependingonthesizeofthemean57. A95%confidenceintervalforapopulationmeanisdeterminedtobe100to120.Iftheconfidencecoefficientisreducedto0.90,theintervalfora.becomesnarrowerb.becomeswiderc.doesnotchanged.becomes0.158. Theabilityofanintervalestimatetocontainthevalueofthepopulationparameterisdescribedbythea.confidencelevelb.degreesoffreedomc.precisevalueofthepopulationmeand.degreesoffreedomminus159. Anintervalestimateisarangeofvaluesusedtoestimatea.theshapeofthepopulation'sdistributionb.thesamplingdistributionc.asamplestatisticd.apopulationparameter60. Indeterminingthesamplesizenecessarytoestimateapopulationproportion,whichofthefollowinginformationisnotneeded?a.themaximummarginoferrorthatcanbetoleratedb.theconfidencelevelrequiredc.apreliminaryestimateofthetruepopulationproportionPd.themeanofthepopulation61. WhattypeoferroroccursifyoufailtorejectH0when,infact,itisnottrue?a.TypeIIb.TypeIc.eitherTypeIorTypeII,dependingonthelevelofsignificanced.eitherTypeIorTypeII,dependingonwhetherthetestisonetailortwotail62. Anassumptionmadeaboutthevalueofapopulationparameteriscalledaa.hypothesisb.conclusionc.confidenced.significance63. TheprobabilityofcommittingaTypeIerrorwhenthenullhypothesisistrueisa.theconfidencelevelb.c.greaterthan1d.theLevelofSignificance 64. Thep-valueisaprobabilitythatmeasuresthesupport(orlackofsupport)forthea.nullhypothesisb.alternativehypothesisc.eitherthenullorthealternativehypothesisd.samplestatistic65. Thep-valuea.isthesameastheZstatisticb.measuresthenumberofstandarddeviationsfromthemeanc.isadistanced.isaprobability66. Inhypothesistestingifthenullhypothesisisrejected,a.noconclusionscanbedrawnfromthetestb.thealternativehypothesisistruec.thedatamusthavebeenaccumulatedincorrectlyd.thesamplesizehasbeentoosmall67. Thelevelofsignificanceisthea.maximumallowableprobabilityofTypeIIerrorb.maximumallowableprobabilityofTypeIerrorc.sameastheconfidencecoefficientd.sameasthep-value68. ATypeIIerroriscommittedwhena.atruealternativehypothesisismistakenlyrejectedb.atruenullhypothesisismistakenlyrejectedc.thesamplesizehasbeentoosmalld.notenoughinformationhasbeenavailable69. Thelevelofsignificancea.canbeanypositivevalueb.canbeanyvaluec.is(1-confidencelevel)d.canbeanyvaluebetween-1.96to1.9670. WhenthefollowinghypothesesarebeingtestedatalevelofsignificanceofH0:500Ha:<500thenullhypothesiswillberejectedifthep-valueisa.b.>c.>/2d.1-/271. Whenthep-valueisusedforhypothesistesting,thenullhypothesisisrejectedifa.p-valueb.<p-valuec.p-valued.p-value=1-72. InordertotestthefollowinghypothesesatanlevelofsignificanceH0:800Ha:>800thenullhypothesiswillberejectediftheteststatisticZisa.Zb.<Zc.<-Zd.=73. Yourinvestmentexecutiveclaimsthattheaverageyearlyrateofreturnonthestockssherecommendsismorethan10.0%.Youplanontakingasampletotestherclaim.Thecorrectsetofhypothesesisa.H0:<10.0%

Ha:10.0%b.H0:10.0%

Ha:>10.0%c.H0:>10.0%

Ha:10.0%d.H0:10.0%

Ha:<10.0%74. AweathermanstatedthattheaveragetemperatureduringJulyinChattanoogaislessthan80degrees.Asampleof32Julysistaken.Thecorrectsetofhypothesesisa.H0:80

Ha:<80b.H0:80

Ha:>80c.H0:80

Ha:=80d.H0:<80

Ha:>8075. Astudentbelievesthattheaveragegradeonthefinalexaminationinstatisticsisatleast85.Sheplansontakingasampletotestherbelief.Thecorrectsetofhypothesesisa.H0:<85

Ha:85b.H0:85

Ha:>85c.H0:85

Ha:<85d.H0:>85

Ha:85 76. Asoftdrinkfillingmachine,wheninperfectadjustment,fillsthebottleswith12ouncesofsoftdrink.Anyoverfillingorunderfillingresultsintheshutdownandreadjustmentofthemachine.Todeterminewhetherornotthemachineisproperlyadjusted,thecorrectsetofhypothesesisa.H0:<12

Ha:12b.H0:12

Ha:>12c.H0:12

Ha:=12d.H0:=12

Ha:1277. Atwo-tailedtestisperformedat95%confidence.Thep-valueisdeterminedtobe0.09.Thenullhypothesisa.mustberejectedb.shouldnotberejectedc.couldberejected,dependingonthesamplesized.hasbeendesignedincorrectly78. Exhibit2n=49=54.8s=28H0:50Ha:>50RefertoExhibit2.Theteststatisticisa.0.1714b.0.3849c.-1.2d.1.279. RefertoExhibit2.Thep-valueisbetweena.0.01to0.025b.0.025to0.05c..05to0.1d.0.1to0.280. RefertoExhibit2.Ifthetestisdoneatthe5%levelofsignificance,thenullhypothesisshoulda.notberejectedb.berejectedc.Notenoughinformationgiventoanswerthisquestion.d.Noneofthesealternativesiscorrect.81. Ifweareinterestedintestingwhetherthemeanofpopulation1issignificantlylargerthanthemeanofpopulation2,thea.nullhypothesisshouldstate1-2>0b.nullhypothesisshouldstate1-20c.alternativehypothesisshouldstate1-2>0d.alternativehypothesisshouldstate1-2<082. Ifweareinterestedintestingwhetherthemeanofpopulation1issignificantlydifferentfromthemeanofpopulation2,thea.nullhypothesisshouldstate1-2=0b.nullhypothesisshouldstate1-20c.alternativehypothesisshouldstate1-2>0d.alternativehypothesisshouldstate1-2<083. Whendevelopinganintervalestimateforthedifferencebetweentwosamplemeans,withsamplesizesofn1andn2,a.N1mustbeequalton2b.N1mustbesmallerthann2c.N1mustbelargerthann2d.N1andn2canbeofdifferentsizes,84. Independentsimplerandomsamplesaretakentotestthedifferencebetweenthemeansoftwopopulationswhosevariancesarenotknown,butareassumedtobeequal.Thesamplesizesaren1=32andn2=40.Thecorrectdistributiontouseisthea.tdistributionwith73degreesoffreedomb.tdistributionwith72degreesoffreedomc.tdistributionwith71degreesoffreedomd.tdistributionwith70degreesoffreedom85. Iftwoindependentlargesamplesaretakenfromtwopopulations,thesamplingdistributionofthedifferencebetweenthetwosamplemeansa.canbeapproximatedbyaPoissondistributionb.willhaveavarianceofonec.canbeapproximatedbyanormaldistributiond.willhaveameanofone86. Thestandarderrorofisthea.varianceofb.varianceofthesamplingdistributionofc.standarddeviationofthesamplingdistributionofd.differencebetweenthetwomeans87. Intheanalysisofvarianceprocedure(ANOVA),"factor"referstoa.thedependentvariableb.theindependentvariablec.differentlevelsofatreatmentd.thecriticalvalueofF88. TheANOVAprocedureisastatisticalapproachfordeterminingwhetherornota.themeansoftwosamplesareequalb.themeansoftwoormoresamplesareequalc.themeansofmorethantwosamplesareequald.themeansoftwoormorepopulationsareequal89. Anexperimentaldesignwheretheexperimentalunitsarerandomlyassignedtothetreatmentsisknownasa.factorblockdesignb.randomfactorpletelyrandomizeddesignd.Noneofthesealternativesiscorrect.90. Inananalysisofvarianceprobleminvolving3treatmentsand10observationspertreatment,SSE=399.6.TheMSEforthissituationisa.133.2b.199.8c.14.8d.30.091. TheFratioinacompletelyrandomizedANOVAistheratioofa.MSTR/MSEb.MST/MSEc.MSE/MSTRd.MSE/MST92. ThecriticalFvaluewith6numeratorand60denominatordegreesoffreedomat=.05isa.3.74b.2.25c.2.37d.1.9693. AnANOVAprocedureisappliedtodataobtainedfrom6sampleswhereeachsamplecontains20observations.ThedegreesoffreedomforthecriticalvalueofFarea.6numeratorand20denominatordegreesoffreedomb.5numeratorand20denominatordegreesoffreedomc.5numeratorand114denominatordegreesoffreedomd.6numeratorand20denominatordegreesoffreedom94. InananalysisofvarianceproblemifSST=120andSSTR=80,thenSSEisa.200b.40c.80d.12095. AnANOVAprocedureisusedfordatathatwasobtainedfromfoursamplegroupseachcomprisedoffiveobservations.ThedegreesoffreedomforthecriticalvalueofFarea.3and20b.3and16c.4and17d.3and1996. InANOVA,whichofthefollowingisnotaffectedbywhetherornotthepopulationmeansareequal?a.b.between-samplesestimateofc.within-samplesestimateofd.Noneofthesealternativesiscorrect.97. Atermthatmeansthesameastheterm"variable"inanANOVAprocedureisa.factorb.treatmentc.replicationd.variancewithinExhibit3Salaryinformationregardingmaleandfemaleemployeesofalargecompanyisshownbelow.MaleFemaleSampleSize6436SampleMeanSalary(in$1,000)4441PopulationVariance()1287298. RefertoExhibit3.Thepointestimateofthedifferencebetweenthemeansofthetwopopulationsisa.-28b.3c.4d.-499. RefertoExhibit3.Thestandarderrorforthedifferencebetweenthetwomeansisa.4b.7.46c.4.24d.2.0100. RefertoExhibit3.At95%confidence,themarginoferrorisa.1.96b.1.645c.3.920d.2.000101. Thecoefficientofdeterminationa.cannotbenegativeb.isthesquarerootofthecoefficientofcorrelationc.isthesameasthecoefficientofcorrelationd.canbenegativeorpositive102.Ifthecoefficientofdeterminationisapositivevalue,thenthecoefficientofcorrelationa.mustalsobepositiveb.mustbezeroc.canbeeithernegativeorpositived.mustbelargerthan1103. Themathematicalequationrelatingtheindependentvariabletotheexpectedvalueofthedependentvariable;thatis,E(y)=0+1x,isknownasa.regressionequationb.correlationequationc.estimatedregressionequationd.regressionmodel104. Themodeldevelopedfromsampledatathathastheformofisknownasa.regressionequationb.correlationequationc.estimatedregressionequationd.regressionmodel105. Theintervalestimateofthemeanvalueofyforagivenvalueofxisa.predictionintervalestimateb.confidenceintervalestimatec.averageregressiond.xversusycorrelationinterval106. Theintervalestimateofanindividualvalueofyforagivenvalueofxisa.predictionintervalestimateb.confidenceintervalestimatec.averageregressiond.xversusycorrelationinterval107. Inaregressionanalysisthestandarderrorisdeterminedtobe4.InthissituationtheMSEa.is2b.is16c.dependsonthesamplesized.dependsonthedegreesoffreedom108