MATLAB: Using aoctool for a 1-way ANCOVA (+plot)

MATLAB: Using aoctool for a 1-way ANCOVA (+plot). plotstatistics. I have two groups of subjects, each with scores on a memory task and on an IQ test. Skiptocontent plotstatistics Ihavetwogroupsofsubjects,eachwithscoresonamemorytaskandonanIQtest.Iwouldliketocheckwhetherthere'sasignificantgroupdifferenceinthememorymeasurewhilecontrollingforIQ. Ireckonedthatforthat,Ineeda1-waybetween-subjectsANCOVA,withDV=memoryscore,predictor=group,andcovariate=IQ.TheMatlabcommandtoachievethisappearstobeaoctool. Followingtheexampleinits(ratherincomplete)documentation,andhavingcodedgroupasacategoricalvariable,Ityped: [h,a,c,s]=aoctool(PIQ,mem,group,0.05,'PIQ','mem','group','off','separatelines'); However,thatjustgivesmetheslopes&interceptsforthegroups,whichdoesnothelpme.WhatIneedisacategoricalcomparisonbetweenthegroups,ratherthanaregressionbetweenxvsy,astheaoctoolexampleseemstoputit. HowcanIuseaoctoolto: obtainap-valueforthebetween-subjectseffectofthegroupfactor? scatter-plotthememoryscoreasafunctionofIQ,withgroupscolor-codedasinthedocumentationexample?Theabovecommanddoesreturnafigurehandleh,butit'sanemptymatrix(eveninthecaseoftheexampledataset!),andIdon'tthinkitcanbeusedtobaseaplotonit. Thanksforanyhelp! BestAnswer Hey,Unfortunately,Ialsodonotknowhowtogetwhatyouwantusingaoctool.However,giventhatnooneelsehasrepliedsofar,Ithoughtyoumightbeinterestedinalternativeways...AsIjusttriedtosolveasimilarproblem,Icameacrossthesetwosolution,whichbothworkfineforcarryingoutanACOVAasyoudescribed:1.Thereisatoolonmatlabcentralfileexchange,whichIfoundveryusefulandeasytouse:https://de.mathworks.com/matlabcentral/fileexchange/27014-mancovan2.BraniVidakovicgivescodeexamplesinthebook"EngineeringBiostatistics:AnIntroductionusingMATLABandWinBUGS".Ithink,Example14.8.describesalmostexactlywhatyouwant,soyoucanjustre-programwhatisshowninthebook.Best,Matthias RelatedSolutionsMATLAB:ComparetheMeansbetweenindividualgroupsinanova Seeifthemultcompare(link)functionwilldowhatyouwant. MATLAB:CurveFittingDiscrepanc​ies–Expon​entialversusLog-Transformed Haveyouseenthis?http://www.mathworks.com/products/statistics/demos.html?file=/products/demos/shipping/stats/xform2lineardemo.html RelatedQuestion3-wayRepeatedMeasuresANOVApairwisecomparisonsusingmultcompareANCOVA(aoctool)with2ormorecovariatesDelimitatextfilebasedoncolumnsofcellsHowtomakeallpossiblepairwisecomparisonsforthethree-wayrepeatedmeasuresANOVA