One-way ANOVA - Laerd Statistics

The one-way analysis of variance (ANOVA) is used to determine whether there are any statistically significant differences between the means of three or more ... TaketheTourPlans&PricingSIGNUP One-wayANOVA Whatisthistestfor? Theone-wayanalysisofvariance(ANOVA)isusedtodeterminewhetherthereareanystatisticallysignificantdifferencesbetweenthemeansofthreeormoreindependent(unrelated)groups.Thisguidewillprovideabriefintroductiontotheone-wayANOVA,includingtheassumptionsofthetestandwhenyoushouldusethistest.Ifyouarefamiliarwiththeone-wayANOVA,butwouldliketocarryoutaone-wayANOVAanalysis,gotoourguide:One-wayANOVAinSPSSStatistics. Whatdoesthistestdo? Theone-wayANOVAcomparesthemeansbetweenthegroupsyouareinterestedinanddetermineswhetheranyofthosemeansarestatisticallysignificantlydifferentfromeachother.Specifically,itteststhenullhypothesis: whereµ=groupmeanandk=numberofgroups.If,however,theone-wayANOVAreturnsastatisticallysignificantresult,weacceptthealternativehypothesis(HA),whichisthatthereareatleasttwogroupmeansthatarestatisticallysignificantlydifferentfromeachother. Atthispoint,itisimportanttorealizethattheone-wayANOVAisanomnibusteststatisticandcannottellyouwhichspecificgroupswerestatisticallysignificantlydifferentfromeachother,onlythatatleasttwogroupswere.Todeterminewhichspecificgroupsdifferedfromeachother,youneedtouseaposthoctest.Posthoctestsaredescribedlaterinthisguide. Jointhe10,000sofstudents,academicsandprofessionalswhorelyonLaerdStatistics.TAKETHETOURPLANS&PRICING Whenmightyouneedtousethistest? Ifyouaredealingwithindividuals,youarelikelytoencounterthissituationusingtwodifferenttypesofstudydesign: Onestudydesignistorecruitagroupofindividualsandthenrandomlysplitthisgroupintothreeormoresmallergroups(i.e.,eachparticipantisallocatedtoone,andonlyone,group).Youthengeteachgrouptoundertakedifferenttasks(orputthemunderdifferentconditions)andmeasuretheoutcome/responseonthesamedependentvariable.Forexample,aresearcherwishestoknowwhetherdifferentpacingstrategiesaffectthetimetocompleteamarathon.Theresearcherrandomlyassignsagroupofvolunteerstoeitheragroupthat(a)startsslowandthenincreasestheirspeed,(b)startsfastandslowsdownor(c)runsatasteadypacethroughout.Thetimetocompletethemarathonistheoutcome(dependent)variable.Thisstudydesignisillustratedschematicallyinthediagrambelow: Whenyoumightusethistestiscontinuedonthenextpage. «prev1234next»