Structural equation modeling (SEM) in JASP allows you to estimate SEM models for multiple groups. To write the syntax for a multigroup SEM model in JASP, you will need to specify which paths are constrained to be equal across the groups.

You can do this by indicating the equality constraints in the path diagram by adding the same label to the path in the different groups. You can use the constrain button in JASP to equalize the path in different groups.

Here is an example of how to write the syntax for a multigroup SEM model with a constrained path:

# Measurement Model

group = {group1, group2}

model {

for (i in 1:2) {

y1 by A1@1;

y2 by A2@1;

}

}

# Structural Model

model {

for (i in 1:2) {

A1 -> y1;

A2 -> y2;

}

# Constrain path A1->y1 to be equal across groups

A1@1 = A1@2;

# Constrain path A2->y2 to be equal across groups

A2@1 = A2@2;

}

Thank you for your answer. I was not able to understand very well the syntax you wrote. So, I have tried to explain my research and what I have done. I have three latent variables and I have aimed to examine a basic mediation model in two groups. First, I followed the recommendation in this web site to test measurement invariance : https://jasp-stats.org/2022/01/25/measurement-invariance-testing-using-the-structural-equation-modeling-sem-module-in-jasp/

So, I wrote the syntax for measurement model as below:

# factor loadings

im =~ mot2 + mot11 + mot12

dp =~ dp1 + dp2 + dp3 + dp4 + dp5

cm =~ cm1 + cm2 + cm3 + cm4 + cm5 + cm6 + cm7 + cm8

Second, I tested scalar invariance:

# factor loadings (labeled equal)

im =~ m1*mot2 + m2*mot11 + m3*mot12

dp =~ d1*dp1 + d2*dp2 + d3*dp3 + d4*dp4 + d5*dp5

cm =~ c1*cm1 + c2*cm2 + c3*cm3 + c4*cm4 + c5*cm5 + c6*cm6 + c7*cm7 + c8*cm8

Third, I wanted to test multigroup model. When I selected the multigroup buttom, JASP gave me the results but I can not understand how I can comment these results. As you said I must need to specify which paths are constrained to be equal across the groups. But I dont know how ı can do this by writing syntax. The syntax you wrote did not totaly match I wrote (You esed { or @ symbols). So I confused, if you have any recommendation, I would be happy.