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1、Analyzing911responsedatausingRegressionThistutorialdemonstrateshowregressionanalysishasbeenimplementedinArcGIS,andexploressomeofthespecialconsiderationsyou’llwanttothinkaboutwheneveryouuseregressionwithspatialdata.Regressionanalysisallowsyoutomodel,examine,andexplorespat
2、ialrelationships,tobetterunderstandthefactorsbehindobservedspatialpatterns,andtopredictoutcomesbasedonthatunderstanding.OrdinaryLeastSquaresregression(OLS)isaglobalregressionmethod.GeographicallyWeightedRegression(GWR)isalocal,spatial,regressionmethodthatallowstherelatio
3、nshipsyouaremodelingtovaryacrossthestudyarea.BothofthesearelocatedintheSpatialStatisticsTools->ModelingSpatialRelationshipstoolset:Beforeexecutingthetoolsandexaminingtheresults,let’sreviewsometerminology:•Dependentvariable(Y):whatyouaretryingtomodelorpredict(residentialb
4、urglaryincidents,forexample).•Explanatoryvariables(X):variablesyoubelieveinfluenceorhelpexplainthedependentvariable(like:income,thenumberofvandalismincidents,orhouseholds).•Coefficients(β):values,computedbytheregressiontool,reflectingtherelationshipandstrengthofeachexpla
5、natoryvariabletothedependentvariable.•Residuals(ε):theportionofthedependentvariablethatisn’texplainedbythemodel;themodelunderandoverpredictions.Thesign(+/-)associatedwiththecoefficient(oneforeachexplanatoryvariable)tellsyouwhethertherelationshipispositiveornegative.Ifyou
6、weremodelingresidentialburglaryandobtainanegativecoefficientfortheIncomevariable,forexample,itwouldmeanthatasmedianincomesinaneighborhoodgoup,thenumberofresidentialburglariesgoesdown.Outputfromregressionanalysiscanbealittleoverwhelmingatfirst.Itincludesdiagnosticsandmode
7、lperformanceindicators.Allofthesenumbersshouldseemmuchlessdauntingonceyoucompletethetutorialbelow.Importantnotes:1.ThestepsinthistutorialdocumentassumethedataisstoredatC:SpatialStats.Ifadifferentlocationisused,substitute"C:SpatialStats"withthealternatelocationwhenenter
8、ingdataandenvironmentpaths.2.ThistutorialwasdevelopedusingArcGIS10.0.Ifyouareusingadifferentversionofth