Mplus Users Guide v6.. - Muthén & Muthén

CHAPTER 3• Wald chi-square test of parameter equalitiesFor continuous, censored with weighted least squares estimation, binary,and ordered categorical (ordinal) outcomes, multiple group analysis isspecified by using the GROUPING option of the VARIABLE commandfor individual data or the NGROUPS option of the DATA command forsummary data. For censored with maximum likelihood estimation,unordered categorical (nominal), and count outcomes, multiple groupanalysis is specified using the KNOWNCLASS option of theVARIABLE command in conjunction with the TYPE=MIXTUREoption of the ANALYSIS command. The default is to estimate themodel under missing data theory using all available data. TheLISTWISE option of the DATA command can be used to delete allobservations from the analysis that have missing values on one or moreof the analysis variables. Corrections to the standard errors and chisquaretest of model fit that take into account stratification, nonindependenceof observations, and unequal probability of selection areobtained by using the TYPE=COMPLEX option of the ANALYSIScommand in conjunction with the STRATIFICATION, CLUSTER, andWEIGHT options of the VARIABLE command. TheSUBPOPULATION option is used to select observations for an analysiswhen a subpopulation (domain) is analyzed. Random slopes arespecified by using the | symbol of the MODEL command in conjunctionwith the ON option of the MODEL command. Linear and non-linearparameter constraints are specified by using the MODELCONSTRAINT command. Indirect effects are specified by using theMODEL INDIRECT command. Maximum likelihood estimation isspecified by using the ESTIMATOR option of the ANALYSIScommand. Bootstrap standard errors are obtained by using theBOOTSTRAP option of the ANALYSIS command. Bootstrapconfidence intervals are obtained by using the BOOTSTRAP option ofthe ANALYSIS command in conjunction with the CINTERVAL optionof the OUTPUT command. The MODEL TEST command is used to testlinear restrictions on the parameters in the MODEL and MODELCONSTRAINT commands using the Wald chi-square test.Graphical displays of observed data and analysis results can be obtainedusing the PLOT command in conjunction with a post-processinggraphics module. The PLOT command provides histograms,scatterplots, plots of individual observed and estimated values, and plotsof sample and estimated means and proportions/probabilities. These are20