mxTryHard status codes
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Rachel
Joined: 02/08/2012
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Dear all,
I have been running a model within a loop over several variables, which does not converge well for all variables. Therefore, I applied mxTryHard. There are two things I noticed:
1) for models that run well without calling mxTryHard the best fit does not seem to change using mxTryHard, but the status code changes from 0 to -1
> fit1 <- mxRun(model,intervals =F)
> fit1$output$Minus2LogLikelihood
[1] 4595.342
> fit1$output$status
$code
[1] 0
$status
[1] 0
fit2<-mxTryHard(model,intervals=F)
> fit2$output$Minus2LogLikelihood
[1] 4595.342
fit2$output$status
$code
[1] -1
$status
[1] 0
2) even when I set "intervals=F" (like in the example above) the mxTryHard option computes intervals.
Can you help?
Thanks in advance
Thanks Rachel. The first bug
Thanks Rachel. The first bug you mention should already be resolved in the development version of OpenMx. The second is a good point, I will adjust this. These changes will be available in the next release, or by building OpenMx from source.
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Thank you!
Thank you!
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Expirience same problem
Hi all,
I experience the same status code = -1 problem in case of any model I run with mxTryHard, be it a model that results in "Solution found", or a model that results: "OpenMx status code 1 greater than 0; Not all eigenvalues of hessian are greater than 0; Retry limit reached, "
I'm running OpenMx version: 2.3.1 [GIT v2.3.1], R version: R version 3.2.1 (2015-06-18), Platform: x86_64-w64-mingw32, Default optimiser: NPSOL, installed from the website.
Does this mean both models converged (MxStatus Green)?
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In reply to Expirience same problem by martonandko
Status code = -1 means
Status code = -1 means premature termination of the optimizer, so I don't think any models converged. Based on the information in your post, I'm not sure what's going on, though. Could you copy-paste the messages printed to the screen by
mxTryHard()?Log in or register to post comments
In reply to Status code = -1 means by AdminRobK
Thanks for having a look at
Thanks for having a look at it!
Limiting the extra runs to 1 to supress output (output the same for 10 extra runs), mxTryHard returns:
Begin fit attempt 1 of at maximum 2 tries
Lowest minimum so far: 461.211751950297
Not all eigenvalues of hessian are greater than 0: 559.193020473922, 486.393117628652, 204.302637390566, 187.97870749209, 174.565171935069, 127.448215232486, 34.6394063711714, 4.85183481710131, 1.37182372473253, -0.127544032337779
Begin fit attempt 2 of at maximum 2 tries
Lowest minimum so far: 461.211751950279
OpenMx status code 1 greater than 0
Not all eigenvalues of hessian are greater than 0: 559.192121639248, 486.392579488029, 204.304599125184, 187.979472270581, 174.565930769942, 127.448041794442, 34.6396697751378, 4.8521695638418, 1.37244146991232, -0.126964546464526
Retry limit reached
Estimate confidence intervals for imperfect solution
Start values from best fit:
0.767557125047236,0.169527920231489,0.414497889243009,0.543614188916936,0.728527002372227,0.505322379565154,0.118637216479181,-0.0932594170628762,1,1
@output$status returns:
$code
[1] -1
$status
[1] 0
In case of a model where it says, solution found:
Begin fit attempt 1 of at maximum 11 tries
Lowest minimum so far: 461.211751950294
OpenMx status code 1 greater than 0
Begin fit attempt 2 of at maximum 11 tries
Lowest minimum so far: 461.211751950276
OpenMx status code 1 greater than 0
Begin fit attempt 3 of at maximum 11 tries
Lowest minimum so far: 461.211751950274
Solution found
Estimating confidence intervals
Start values from best fit:
0.767557199351073,0.169527720018016,0.414497827985777,0.543614118267592,0.728526940730898,0.505322361547715,0.11863739923075,-0.0932593099645859,1
But the status is the same as the previuos model:
$code
[1] -1
$status
[1] 0
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In reply to Thanks for having a look at by martonandko
status code is probably spurious
Hmm. OK, it would appear that the optimizer is NOT terminating prematurely. I would guess that the second model in your post converged, but that the first one (with just one extra try) didn't.
I think the status code of -1 is spurious, and due to a bug.
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In reply to status code is probably spurious by AdminRobK
Is there a work around?
Thanks for the information! mxTryHard really seems like a nice tool, hope the bug can be fixed easily. Is there a way to identify mxTryHard runs which terminate with a solution, other than the status code for the time being?
Two other interesting things, which might be bugs is:
-if I rerun a fitted model, which was fitted with mxTryHard with the simple mxRun command, the status code stays -1 for all models.
-if I don't include the "intervals = T" command in the mxTryHard command, and rerun the fitted model with the simple mxRun command with the "intervals = T" command, then it doesn't calculate the confidence intervals.
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In reply to Is there a work around? by martonandko
Thanks for pointing these
Thanks for pointing these out, they all stem from the one issue which needs to be fixed really. For the moment, a work around would be to use omxGetParameters() to extract the estimates from the mxTryhard with intervals=F solution, and omxSetParameters() to assign these values to an unfitted model, then fit this with mxRun and intervals=T. Or just pay attention to whether mxtryhard reports 'solution found' or not - this indicates that the fit prior to estimating confidence intervals was accepted, and confidence interval estimation won't change this. Sorry for the fuss! :)
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In reply to Expirience same problem by martonandko
Any chance you can supply a
*deleted my comment and taking a look*
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