Longitudinal and multi group studies

Frequently asked questions about PLS path modeling.
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shamilaj
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Real name and title: Mrs. Shamila J

Longitudinal and multi group studies

Post by shamilaj »

Hi,

Please refer me to longitudinal studies that also used multi groups. I am trying to do a study using 2 groups and collected data during 2 different time points. I am looking for example studies to make sure what I am doing is correct.

Any help will be much appreciated.

Thank you.
jmbecker
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Re: Longitudinal and multi group studies

Post by jmbecker »

I'm not aware of longitudinal studies that use PLS-MGA. The problem is that PLS-MGA assumes independence of the groups. However, in a longitudinal setting groups are not independent, just like in a paired t-test.

If you have strictly paired data, I would rather model both time points in the same model (maybe even including autoregressive effects).
Dr. Jan-Michael Becker, University of Cologne, SmartPLS Developer
Researchgate: https://www.researchgate.net/profile/Jan_Michael_Becker
GoogleScholar: http://scholar.google.de/citations?user ... AAAJ&hl=de
shamilaj
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Real name and title: Mrs. Shamila J

Re: Longitudinal and multi group studies

Post by shamilaj »

Thank you very much Dr. Becker.

What you said makes sense. I did as you said and put both time points within the same model. To test difference between the 2 groups do I just look at p-value (condition 1 Vs condition 2) in the PLS-MGA or parametric test?

-Shamila
jmbecker
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Re: Longitudinal and multi group studies

Post by jmbecker »

If you have everything in one model you can test parameters in t1 vs. t2 with the following approach
Rodríguez-Entrena, M., Schuberth, F., & Gelhard, C. (2018). Assessing statistical differences between parameters estimates in Partial Least Squares path modeling. Quality & quantity, 52(1), 57-69.
Dr. Jan-Michael Becker, University of Cologne, SmartPLS Developer
Researchgate: https://www.researchgate.net/profile/Jan_Michael_Becker
GoogleScholar: http://scholar.google.de/citations?user ... AAAJ&hl=de
shamilaj
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Joined: Mon Aug 26, 2019 11:57 am
Real name and title: Mrs. Shamila J

Re: Longitudinal and multi group studies

Post by shamilaj »

Thank you very much Dr. Becker.

In this paper they talk about using MS Excel "in order to manually calculate the parameter difference for
every bootstrap sample" (p.63). I used SmartPLS 3.0 hence I think this operation is completed by the software itself. Correct me if I am wrong.

-Shamila
meldarien
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Real name and title: Melvin Prince

Re: Longitudinal and multi group studies

Post by meldarien »

What about running the same model independently for t1 and t2? Then use the latent variable scores (or the unstandardized ones from IPMA) for partial least squares regressions in the structural model. Is this ok? Is there a literature that provides support or context?

Melvin Prince
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