Mplus Users Guide v6.. - Muthén & Muthén

MODEL Commandthe outcome in a growth model. The variables on the left-hand side ofAT are paired with the variables on the right-hand side of AT.The intercepts of the outcome variables are fixed at zero as the default.The residual variances of the outcome variables are free to be estimatedas the default. The residual covariances of the outcome variables arefixed at zero as the default. The means, variances, and covariances ofthe intercept and slope growth factors are free as the default.XWITHThe XWITH option is used with TYPE=RANDOM to defineinteractions between continuous latent variables or between a continuouslatent variable and an observed variable. XWITH is short for multipliedwith. It is used in conjunction with the | symbol to name and defineinteraction variables in a model. Following is an example of how to useXWITH and the | symbol to name and define an interaction:int | f1 XWITH f2;where int is the name of the interaction between f1 and f2. Interactionvariables can be used only on the right-hand side of ON statements.The XWITH option can be used to create an interaction variable that isthe square of a latent variable. Following is an example of how this isspecified:fsquare | f XWITH f;Latent variable interactions are estimated using maximum likelihood forall regular models as well as mixture models and multilevel models.Interactions are allowed between continuous latent variables andbetween a continuous latent variable and an observed variable. Factorindicators for the continuous latent variables can be continuous,censored, binary, ordered categorical (ordinal), counts, or combinationsof these variable types. Observed variables in the interaction can beindependent or mediating variables and the mediating variables can becensored, binary, ordered categorical (ordinal), counts, or combinationsof these variable types. Dependent observed variables in the interactioncan have missing data. In many cases, numerical integration is requiredin the maximum likelihood estimation of latent variable interactions.611