I'm learning SEM with the OpenMx documentation. First of all thanks for this I would agree your effort and attention.

I'm a beginner in SEM and I'm not sure about this question. I see a possible bug in documentation http://openmx.psyc.virginia.edu/docs/OpenMx/latest/Regression_Path.html. The specification of a multiple regression and multivariate regression talk about the covariance between x and z in a y equation (resp. z equation). This relation is specified in scripts like:

# covariance of x and z

mxPath(

from="x",

to="y",

arrows=2,

free=TRUE,

values=0.5,

labels="covxz"

),

Is this correct or have to be:

# covariance of x and z

mxPath(

from="x",

to="z",

arrows=2,

free=TRUE,

values=0.5,

labels="covxz"

),

I see the same thing in the graph specification (with sigmaxy).

thanks in advance,

Ferran Carrascosa