Problem with dimnames and thresholds
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summary(fooModel) should return S3 or S4 object
"mySummary <- summary(fooModel)" prints the whole summary, but should be silent and print nothing.
Alternative estimate of the Hessian
The attached R script, when run, shows that NPSOL's Hessian* is incorrect when the model is underidentified (more free parameters than statistics). As a result a user could be misled into thinking that a model is identified when it is not. A better picture emerges when numDeriv is used.
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Need Mx1's mnor() and allint function
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OpenMx 0.2.3-1006 includes mixture distributions!
The biggest news is that mixture distribution models are now supported. We have tested using some models with known outcomes for continuous variables and for ordinal variables. Documentation on mixture distributions is not ready yet, so if you are interested in fitting this type of model, please go to the Mixture Distribution and Latent Class Models forum page for discussion.
Getting df right
Let's try to get df correct in OpenMx. We thought this was a priority at the meeting yesterday. There are one or two things to consider, however, when it comes to raw data input because the statistics are not counted the same way in every software package.
In general, df = nstats - nparameters
Suppose there are i=1...ng groups (submodels) in the model. Let the number of variables in submodel i be m_i. Let the number of nonlinear equality constraints be nk. Then, for only covariance matrix input we have:
nstats(cov)= sum_i {m_i*(m_i + 1)/2} + nk
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Note that we have additional version of...
http://openmx.psyc.virginia.edu/docs/OpenMx/latest/TwoModelStylesTwoDataStyles.html#univariate-saturated-model
This sentence
Note that we have additional version of the matrix-style examples which use a Cholesky decomposition to estimate the expected covariance matrices, which is preferred to directly estimation the symmetric matrices.
should read
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mxData: cov to take lower, upper, and full?
i.e., that this would work:
data = read.moments(file = "", diag = T)
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.3 1
.4 .35 1
mxData(data, type="cov",numObs=100)
without first requiring
data[upper.tri(data)] = data[lower.tri(data)]
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value labels on path diagrams
anyhow, the working functions are here
trunk/models/failing/addValue.R
if you paste them into R you can use
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