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My question involves a MIMIC model where I intend to compare a baseline LGM to an LGM nested within it (wherein intercept and slope paths are freed) using the traditional Chisquare difference test. My (abbreviated) syntax is included below: BASELINE MODEL: GROUPING IS PRCATO15_2cat (1 = secure 2 = insecure); MODEL: I S  STANXX1F@0 STANXXG3@.25 STANXXG5@.5 STANXXG6@.6 STANXXX5@1; I S on L08X5MEAN_R; STANXX1F STANXXG3 STANXXG5 STANXXG6 STANXXX5(1); OUTPUT: SAMPSTAT; STANDARDIZED; NESTED MODEL: GROUPING IS PRCATO15_2cat (1 = secure 2 = insecure); MODEL: I S  STANXX1F@0 STANXXG3@.25 STANXXG5@.5 STANXXG6@.6 STANXXX5@1; I S on L08X5MEAN_R; STANXX1F STANXXG3 STANXXG5 STANXXG6 STANXXX5(1); MODEL secure: I S on L08X5MEAN_R; OUTPUT: SAMPSTAT; STANDARDIZED; When I run this syntax, the degrees of freedom between the baseline and nested models are identical. How is this possible if I'm specifying the freeing of I S on L08X5MEAN_R; for the secure group? I appreciate any help you can provide. 


There is no difference between the two models. The ON statement you mention in the groupspecific MODEL command is not constrained to be equal as the default. 


To make the statement "I S on L08X5MEAN_R" equal between groups the default in the baseline model, would this work: BASELINE MODEL: GROUPING IS PRCATO15_2cat (1 = secure 2 = insecure); MODEL: I S  STANXX1F@0 STANXXG3@.25 STANXXG5@.5 STANXXG6@.6 STANXXX5@1; I S on L08X5MEAN_R; STANXX1F STANXXG3 STANXXG5 STANXXG6 STANXXX5(1); MODEL secure: I S  STANXX1F@0 STANXXG3@.25 STANXXG5@.5 STANXXG6@.6 STANXXX5@1(p1); I S on L08X5MEAN_R(p2); STANXX1F STANXXG3 STANXXG5 STANXXG6 STANXXX5(1); MODEL insecure: I S  STANXX1F@0 STANXXG3@.25 STANXXG5@.5 STANXXG6@.6 STANXXX5@1(p3); I S on L08X5MEAN_R(p4); STANXX1F STANXXG3 STANXXG5 STANXXG6 STANXXX5(1); MODEL CONSTRAINT: 0 = p1  p3 0 = p2  p4 OUTPUT: SAMPSTAT; STANDARDIZED; Thanks again for your help! 


You should place the equality in the general MODEL command: MODEL: I S  STANXX1F@0 STANXXG3@.25 STANXXG5@.5 STANXXG6@.6 STANXXX5@1; I on L08X5MEAN_R (10); S on L08X5MEAN_R (11); 


So, just to be clear, the syntax would read: BASELINE MODEL: GROUPING IS PRCATO15_2cat (1 = secure 2 = insecure); MODEL: I S  STANXX1F@0 STANXXG3@.25 STANXXG5@.5 STANXXG6@.6 STANXXX5@1; I on L08X5MEAN_R (10); s on L08X5MEAN_R (11); STANXX1F STANXXG3 STANXXG5 STANXXG6 STANXXX5(1); MODEL secure: I S  STANXX1F@0 STANXXG3@.25 STANXXG5@.5 STANXXG6@.6 STANXXX5@1; I on L08X5MEAN_R (10); s on L08X5MEAN_R (11); STANXX1F STANXXG3 STANXXG5 STANXXG6 STANXXX5(1); MODEL insecure: I S  STANXX1F@0 STANXXG3@.25 STANXXG5@.5 STANXXG6@.6 STANXXX5@1; I on L08X5MEAN_R (10); s on L08X5MEAN_R (11); STANXX1F STANXXG3 STANXXG5 STANXXG6 STANXXX5(1); OUTPUT: SAMPSTAT; STANDARDIZED; Thanks again! 


You don't need the groupspecific MODEL commands. They are redundant. There is a section in Chapter 14 of the user's guide that discusses multiple group analysis. 

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