Mplus Users Guide v6.. - Muthén & Muthén

Examples: Growth Modeling And Survival Analysisgrowth factor are fixed at one as part of the growth modelparameterization. The residual variances of the outcome variables areestimated and allowed to be different across time and the residuals arenot correlated as the default.In the parameterization of the growth model shown here, the interceptsof the outcome variables at the four time points are fixed at zero as thedefault. The means and variances of the growth factors are estimated asthe default, and the growth factor covariance is estimated as the defaultbecause the growth factors are independent (exogenous) variables. Thedefault estimator for this type of analysis is maximum likelihood. TheESTIMATOR option of the ANALYSIS command can be used to selecta different estimator.EXAMPLE 6.2: LINEAR GROWTH MODEL FOR ACENSORED OUTCOME USING A CENSORED MODELTITLE: this is an example of a linear growthmodel for a censored outcome using acensored modelDATA: FILE IS ex6.2.dat;VARIABLE: NAMES ARE y11-y14 x1 x2 x31-x34;USEVARIABLES ARE y11-y14;CENSORED ARE y11-y14 (b);ANALYSIS: ESTIMATOR = MLR;MODEL: i s | y11@0 y12@1 y13@2 y14@3;OUTPUT: TECH1 TECH8;The difference between this example and Example 6.1 is that theoutcome variable is a censored variable instead of a continuous variable.The CENSORED option is used to specify which dependent variablesare treated as censored variables in the model and its estimation, whetherthey are censored from above or below, and whether a censored orcensored-inflated model will be estimated. In the example above, y11,y12, y13, and y14 are censored variables. They represent the outcomevariable measured at four equidistant occasions. The b in parenthesesfollowing y11-y14 indicates that y11, y12, y13, and y14 are censoredfrom below, that is, have floor effects, and that the model is a censoredregression model. The censoring limit is determined from the data. Theresidual variances of the outcome variables are estimated and allowed to103