Mplus Discussion >> Negative chi | chi square difference
Message/AuthorHiBengtandLinda,Imtestingforgenderdifferencesanautoregressivecross-laggedmodelusingamultiplegroupmodel(boysvs.girls).FirstIlettheparametersfreeforboysandgirls.ThenIrerunthemodelwiththeparameterestimatesequalbetweenboysandgirls.Asaresult,thechi-squareofthemodelwithfreeestimateshasahigherchi-square(andofcoursefewerDf)thantheonewiththefixedparameters,resultinginanegativechi-squaredifferencevalue.Isanegativechi-squaredifferenceacceptable?Andifyes,shallIreportthevaluewiththenegative...
Message/Author Hi Bengt and Linda,Im testing for gender differences an autoregressive cross-lagged model using a multiple group model (boys vs. girls). First I let the parameters free for boys and girls. Then I rerun the model with the parameter estimates equal between boys and girls. As a result, the chi-square of the model with free estimates has a higher chi-square (and of course fewer Df) than the one with the fixed parameters, resulting in a negative chi-square difference value.
Is a negative chi-square difference acceptable? And if yes, shall I report the value with the negative sign?
Thanks.
If you are using MLM or MLR, this can happen and the results are not meaningful. Hi Linda,thank you for the fast reply.
Could you please clarify me something?
What did you mean by "the results are not meaningful"? Does it mean that the chi-square test is not valid? Or that the differences Ive found between boys and girls in the free ...