如何做spm8第二阶段

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1、GroupAnalysis(RandomEffectsAnalysis)Inordertorunthegroupstatisticalanalysis,allimagesmustbethesamesize,havethesamevoxelsizesandthesameorigins.If.matfilesarepresent(notethattheyoftenarenotfortheswrimages),thentheymustallcontainidenticalinformation.Thismeansnotonlythattheyshouldbeginasimagesofequiv

2、alentsizeanddimensions,butthattheyshouldbenormalizedandsmoothedtothesamesizes.Presumably,youshouldworkwithastatisticallysignificantnumberofsubjects(perhaps6?)Whatyoushoulddo:Groupanalysisisconsiderablyeasierifalldataispreprocessedandanalyzedthesamewayandcontrastswereallenteredinthesameorderforeac

3、hsubject.Makeadirectoryforthegroupanalysis,soyoudon’toverwritefiles(SPM.matandalltheimagesresultingfromEstimation)inyoursubjectdirectories.MakesureyouareinyournewgroupdirectoryinMatlab,thenstartSPM.SelectDesignType->OneSamplet-test?OneSampleT-Test:Isthemeansignalvaluedifferentthan0??

4、TwoSampleT-Test:IsthemeansignalvalueofGroup1differentthanGroup2??PairedT-Test:IsthemeansignalvalueofCondition1differentthanCondition2(foronegroup)??OneWayAnova:Isthemeansignalvalueof3ormoregroups/conditionsdifferent??SimpleRegression(Correlation):Doesthevariable'a'inalinearregressionequal0?y=ax+b

5、(yisthevalueofthecontrastandxthepredictivefactor)?MultipleRegression:Doesthevariable'a'inalinearregressionequal0foreachpredictor?y=a1x1+anxn+b(yisthevalueofthecontrastandx1…nthepredictivefactors)?Ancova:Doesthemeansignalvalueofagroup/condition1differfromoneormoreothergroups/conditionswhentheeffec

6、tofapredictivefactorxiscontrolled?”SelectImages”(Navigatethrougheachsubjectdirectoryandchoosethecorrectcon*.imgbyclickingit.DoNOThit“Done”untilyouhaveselectedalltheindividualimagesthatwillcontributetothatgroupanalysis.GMsca:GrandMeanScaling:explicitlymaskimages:NoGlobalCalcula

7、tions:OmitAnewSPM.matiscreatedEstimate:(SelectthenewlycreatedSPM.mat)Allofthefilesthatestimationusuallycreatesarecreatedforthegroupanalysis:betaimgandhdr;maskimgandhdr,ResMSimgandhdr,RPVimgandhdr)Whenitruns(whichshould