商务统计学（英文版第7版）教学课件BSFC7e_CH13.ppt

IntroductiontoMultipleRegressionChapter13

ObjectivesInthischapter,youlearn:HowtodevelopamultipleregressionmodelHowtointerprettheregressioncoefficientsHowtodeterminewhichindependentvariablestoincludeintheregressionmodelHowtousecategoricalindependentvariablesinaregressionmodel

TheMultipleRegressionModelIdea:Examinethelinearrelationshipbetween1dependent(Y)2ormoreindependentvariables(Xi)MultipleRegressionModelwithkIndependentVariables:Y-interceptPopulationslopesRandomErrorDCOVA

MultipleRegressionEquationThecoefficientsofthemultipleregressionmodelareestimatedusingsampledataEstimated(orpredicted)valueofYEstimatedslopecoefficientsMultipleregressionequationwithkindependentvariables:EstimatedinterceptInthischapterwewilluseExcelandMinitabtoobtaintheregressionslopecoefficientsandotherregressionsummarymeasures.DCOVA

TwovariablemodelYX1X2SlopeforvariableX1SlopeforvariableX2MultipleRegressionEquation(continued)DCOVA

AdistributoroffrozendessertpieswantstoevaluatefactorsthoughttoinfluencedemandDependentvariable:Piesales(unitsperweek)Independentvariables:Price(in$) Advertising($100’s)Dataarecollectedfor15weeksExample:

2IndependentVariablesDCOVA

PieSalesExampleSales=b0+b1(Price) +b2(Advertising)WeekPieSalesPrice($)Advertising($100s)13505.503.324607.503.333508.003.044308.004.553506.803.063807.504.074304.503.084706.403.794507.003.5104905.004.0113407.203.5123007.903.2134405.904.0144505.003.5153007.002.7Multipleregressionequation:DCOVA

ExcelMultipleRegressionOutputRegressionStatisticsMultipleR0.72213RSquare0.52148AdjustedRSquare0.44172StandardError47.46341Observations15ANOVA?dfSSMSFSignificanceFRegression2294600136.538610.01201Residual1227033.3062252.776Total1456493.333????CoefficientsStandardErrortStatP-valueLower95%Upper95%Intercept306253892.682850.0199357.58835