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GEE和QIF用于含有缺失数据的AsthmaData数据分析 Introduction Asthmaisachronicrespiratorydiseasethataffectspeopleofallagesworldwide.Itischaracterizedbyinflammationinthebronchialtubes,whichleadstowheezing,difficultybreathing,andcoughing.Themanagementofasthmarequiresroutinemonitoringandassessmentofpatients'symptomseverityandmedicationusage.However,asthmadataanalysiscanbechallengingduetothepresenceofmissingdata.Missingdatamayariseduetovariousreasons,includingpatientnon-compliance,incompletedatacollection,ormeasurementerrors. Thispaperexplorestheuseoftwostatisticalmethods,namelyGeneralizedEstimatingEquations(GEE)andQuadraticInferenceFunctions(QIF),inanalyzingasthmadatawithmissingobservations.Thepaperwillalsodiscusshowthesemethodscanbeappliedtoestimateparameters,identifytheeffectsofpotentialriskfactors,andderiveaccurateconclusionsfromincompletedata. GeneralizedEstimatingEquations(GEE) GEEisapopularmethodforhandlingmissingdatainasthmaresearch.Itisaregression-basedapproachthatestimatesthepopulationaverageofaresponsevariablewhileaccountingforthecorrelationamongrepeatedmeasurementsonthesamesubject.GEEisparticularlyusefulwhenthedataaremissingatrandom(MAR),meaningthattheprobabilityofmissingnessisnotassociatedwiththeunobservedvalueitself,butotherobservedvariables. Inthecontextofasthmadataanalysis,GEEcanbeusedtomodeltherelationshipbetweenapatient'sasthmaseverityandpotentialriskfactorssuchasage,sex,race,smokingstatus,andmedicationusage.GEEhastheadvantageofhandlingmissingdatawithouttheneedtoimputethemissingvalues.Instead,itusesallavailabledatatoestimatethemodelparametersandderiveunbiasedresults.GEEalsoallowsfortheinclusionofcovariatesthatmayaffectthemissingnesspatternandprovidesestimatesthatarerobusttonon-normalityandheteroscedasticity. QuadraticInferenceFunctions(QIF) QIFisanalternativemethodforhandlingmissingdatathatisbasedonthemaximumlikelihoodestimation(MLE)framework.QIFusesaquadraticinferencefunctiontoestimatethemodelparametersbymaximizingthelikelihoodoftheobserveddataandimputingthemissingvalu