How to test the significant difference between measured value ...

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You could either shift your data to have zero mean (ie subtract the expected mean from your data points) or in MATLAB use ttest(x,m) where x ... Home Public Questions Tags Users Companies Collectives ExploreCollectives Teams StackOverflowforTeams –Startcollaboratingandsharingorganizationalknowledge. CreateafreeTeam WhyTeams? Teams CreatefreeTeam Collectives™onStackOverflow Findcentralized,trustedcontentandcollaboratearoundthetechnologiesyouusemost. LearnmoreaboutCollectives Teams Q&Aforwork Connectandshareknowledgewithinasinglelocationthatisstructuredandeasytosearch. LearnmoreaboutTeams Howtotestthesignificantdifferencebetweenmeasuredvaluematlab? AskQuestion Asked 1year,1monthago Modified 1year,1monthago Viewed 243times 0 New!Savequestionsoranswersandorganizeyourfavoritecontent.Learnmore. IhaveanOutputsampleforelectroniccomponentsandIwouldliketoknowthep-valueforrobustmysystemis.Ideally,Iwouldliketogetap-value(P<0.05)toprovethatmysystemcanconstantlyproducethesameresults.Noting,mydatasamplesaresmall. MyOutput: sample=[2.180213,2.178298,2.310851,2.114255,3.012553,2.69234,2.079787]; Itriedusing: [h,p]=chi2gof(sample,'CDF',pd) [h,p,ci,stats]=ttest(x) [h,p,stats]=fishertest(x) [h,p,ksstat,cv]=kstest(___) Iamlost!whatkindoftestdoIperformonMATLABtotrulytesthowclosemyoutputsarefromeachotherandhowconsistentmysystemoutputis(usingp-value)? Edit: Itriedthis: sample=[2.180213,2.178298,2.310851,2.114255,3.012553,2.69234,2.079787]; n=numel(sample); xobs=mean(sample);%Samplemean s=std(sample);%Samplestandarddeviation [h,p]=ttest(sample,xobs) Theresultis: h= 0 p= 1 Mynumbersarekindofclosetoeachotherbuttheresultsdonotmakesense.h=0meansthatthemeanistrueandnotrejected,butthep-valueis1!Whyisithigh! matlabp-valueconsistencyhypothesis-test Share Improvethisquestion Follow editedSep15,2021at23:10 AnwarElhadad askedSep15,2021at20:21 AnwarElhadadAnwarElhadad 111bronzebadge 8 1 Unlessyouarecomparingtwosamples(setofobservations).Inyourquestionyouhaveonesampleconsistingof7observations.Youcouldcomputestandard-deviation(std)orstandard-error(togetasenseofvariability).However,withasinglesampleyoucouldtestthehypothesisthatthesamplemeanusinga1-samplet-test. – AzimJ Sep15,2021at21:22 Ithoughtthe1-samplet-testisforwhenthedatainxcomesfromanormaldistributionwithameanequaltozero.however,mymeanisnotzero@AzimJ – AnwarElhadad Sep15,2021at21:58 yesthegeneric1-samplet-testassumesameanofzero.Youcouldeithershiftyourdatatohavezeromean(iesubtracttheexpectedmeanfromyourdatapoints)orinMATLABusettest(x,m)wherexisyoursampleandmtheexpectedmean(mathworks.com/help/stats/ttest.html-seettest(x,m)fortestingnon-zeromean).Thedatastillneedstocomefromanormallydistributedpopulation. – AzimJ Sep15,2021at22:51 Youaretestingwhetheryourdatacomesfromanormaldistributionwithmeanxobs,whichitlookslikebecauseyoudeterminedxobsfromyoursamples.Thatistosay,yourtestmakesnosense.Ihighlysuggestyoustudystatisticsbeforeyourandomlyapplystatisticaltestswithoutknowingwhattheymean.Notethatapplyingatestandgettingap<0.05provesnothing.Thetesttellsyouwhetheryoucanorcannotdiscardyourhypothesis.It’snotaproof,it’sevidence. – CrisLuengo Sep15,2021at23:22 1 Theonlythingyoucandowithyourdataiscomputeameanandastandarddeviation,anddetermineifyourmeaniscloseenoughtotheexpectedmean,andyourstandarddeviationissmallenoughforyourrequirements.Oryoucanseeifthere’satrendinthedata(meanvaluechangesovertime).Ifyoumustapplyastatisticaltest,youcancompareyourdatatoanexpecteddistribution.Butitlookslikeyoudon’thaveoneofthose,youdon’tevenknowwhatmeanyouexpect? – CrisLuengo Sep15,2021at23:26  |  Show3morecomments 1Answer 1 Sortedby: Resettodefault Highestscore(default) Trending(recentvotescountmore) Datemodified(newestfirst) Datecreated(oldestfirst) 0 IbelieveIfiguredItout.IselectedanarbitrarymeanwhichismydesiredvaluetooutputtedIdeallyanduseitasthehypothesiscondition. sample=[2.180213,2.178298,2.310851,2.114255,3.012553,2.69234,2.079787]; n=numel(sample); xobs=mean(sample);%Samplemean s=std(sample);%Samplestandarddeviation [h,p]=ttest(sample,3) Share Improvethisanswer Follow answeredSep16,2021at0:22 AnwarElhadadAnwarElhadad 111bronzebadge Addacomment  |  YourAnswer ThanksforcontributingananswertoStackOverflow!Pleasebesuretoanswerthequestion.Providedetailsandshareyourresearch!Butavoid…Askingforhelp,clarification,orrespondingtootheranswers.Makingstatementsbasedonopinion;backthemupwithreferencesorpersonalexperience.Tolearnmore,seeourtipsonwritinggreatanswers. Draftsaved Draftdiscarded Signuporlogin SignupusingGoogle SignupusingFacebook SignupusingEmailandPassword Submit Postasaguest Name Email Required,butnevershown PostYourAnswer Discard Byclicking“PostYourAnswer”,youagreetoourtermsofservice,privacypolicyandcookiepolicy Nottheansweryou'relookingfor?Browseotherquestionstaggedmatlabp-valueconsistencyhypothesis-testoraskyourownquestion. TheOverflowBlog Privacy-friendlymachinelearningdatasets:syntheticdata  Bewarethescammersposingastechrecruiters(Ep.497) FeaturedonMeta BookmarkshaveevolvedintoSaves Inboximprovements:markingnotificationsasread/unread,andafiltered... 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