OpenMx - Dynamical Systems and Differential Equations Models
http://openmx.ssri.psu.edu/taxonomy/term/22
Discussions dynamic factor analysis and continuous and discrete time dynamical systems models.
enDerivative Estimation Methods for 3 time occasions?
http://openmx.ssri.psu.edu/thread/3946
<div class="field field-name-taxonomy-forums field-type-taxonomy-term-reference field-label-above"><div class="field-label">Forums: </div><div class="field-items"><div class="field-item even"><a href="/forums/opensem-forums/dynamical-systems-and-differential-equations-models">Dynamical Systems and Differential Equations Models</a></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><div class="tex2jax">
<p>I am planning on using on using multivariate latent differential equation modeling for my MA thesis. I will have the opportunity to plan for the parameters, methods, and measurements required to do so. But currently, I am attempting to utilize one of these derivative estimation methods on some data I currently have. Specifically, I have 3 measurements of PTSD, Cortisol, and Coping Self-Efficacy. The downside is that there are 50 participants and the occasions are not equally spaced (e.g., Time 1 is 1 week after traumatic event, Time 2 is 1 month, and Time 3 is 3 months). Is there a way I can still use this data to create a dynamic (DiffEq) multivariate model to better understand the process of this system of variables?</p>
<p>If not, I understand. From my understanding of reading Boker's and Deboeck's articles and book chapters, this should not work. I just felt like it could not hurt to ask. Any help is appreciated :)</p>
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</div></div></div>Thu, 29 Jan 2015 01:22:23 +0000amullings093946 at http://openmx.ssri.psu.eduhttp://openmx.ssri.psu.edu/thread/3946#commentsExample Script for LDE estimation
http://openmx.ssri.psu.edu/thread/144
<div class="field field-name-upload field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><table class="sticky-enabled">
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<tr class="odd"><td><span class="file"><img class="file-icon" alt="Plain text icon" title="text/plain" src="/modules/file/icons/text-plain.png" /> <a href="http://openmx.ssri.psu.edu/sites/default/files/demoOscillator.txt" type="text/plain; length=1058" title="demoOscillator.txt">demoOscillator.txt</a></span></td><td>1.03 KB</td> </tr>
<tr class="even"><td><span class="file"><img class="file-icon" alt="Binary Data" title="application/octet-stream" src="/modules/file/icons/application-octet-stream.png" /> <a href="http://openmx.ssri.psu.edu/sites/default/files/LDE_2ndOrder_OneIndicator.R" type="application/octet-stream; length=3609" title="LDE_2ndOrder_OneIndicator.R">LDE_2ndOrder_OneIndicator.R</a></span></td><td>3.52 KB</td> </tr>
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</div></div></div><div class="field field-name-taxonomy-forums field-type-taxonomy-term-reference field-label-above"><div class="field-label">Forums: </div><div class="field-items"><div class="field-item even"><a href="/forums/opensem-forums/dynamical-systems-and-differential-equations-models">Dynamical Systems and Differential Equations Models</a></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><div class="tex2jax">
<p>Here is a very basic script for a univariate second order differential equation that Pascal Deboeck and I wrote yesterday. This is the infamous damped linear oscillator.</p>
<p>In order to give you some sample data to run it on, I have attached a data file and used a read.table file that accesses the data file in this post using its URL.</p>
<p>If you have comments, I'd like to hear them!</p>
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</div></div></div>Sun, 06 Sep 2009 20:21:32 +0000Steve144 at http://openmx.ssri.psu.eduhttp://openmx.ssri.psu.edu/thread/144#comments