latent variable correlations - test of hypotheses
latent variable correlations - test of hypotheses
Dear users,
I have got a big problem at the end of my thesis. I would be very thankful if anybody might help me...
I want to verify some hypotheses about correlations of latent variables. In my specific case there are three latent variables. One of them is measured reflective, the others are formative constructs. The output of PLS gives me information about the absolute correlations of the latent variables. 2 question rise up:
a) I'am searching for an information which helps me to verify the hypotheses. Is there any possibility to test them with a statistical proof?
b) Is there a possibility to model correlations in PLS? When I try to model a correlation between to latent constructs, I get a notice "There must be valid path model for calculation".
Thanks a lot for your help!
Michael
I have got a big problem at the end of my thesis. I would be very thankful if anybody might help me...
I want to verify some hypotheses about correlations of latent variables. In my specific case there are three latent variables. One of them is measured reflective, the others are formative constructs. The output of PLS gives me information about the absolute correlations of the latent variables. 2 question rise up:
a) I'am searching for an information which helps me to verify the hypotheses. Is there any possibility to test them with a statistical proof?
b) Is there a possibility to model correlations in PLS? When I try to model a correlation between to latent constructs, I get a notice "There must be valid path model for calculation".
Thanks a lot for your help!
Michael
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Hello Micheal,
did you correctly import your data into PLS? (.csv file, variable names in the first row, only numbers starting with the first column).
You use PLS to test your hypotheses if there are complex relations between the variables. (actually PLS is predicition oriented, Lisrel would be even better suited for complex relations, but it's not a freeware and it needs much bigger sample sizes than a PLS model) If there is only one dependent variable, you can do a simple multiple regression in Spss or Excel.
You have to evaluate the measurement model as well as the structural model (your hypothesized correlations). The path coefficients in PLS are the same as regression coefficients. With the bootstrap method you can calculate t-values for you paths.
See this forum and the working papers by Ringle on the measures that help you determine how well your model fits the data. The site by Prof. W.Chin should also be of good use (just google for "chin pls" )
I hope this helps
Philipp
did you correctly import your data into PLS? (.csv file, variable names in the first row, only numbers starting with the first column).
You use PLS to test your hypotheses if there are complex relations between the variables. (actually PLS is predicition oriented, Lisrel would be even better suited for complex relations, but it's not a freeware and it needs much bigger sample sizes than a PLS model) If there is only one dependent variable, you can do a simple multiple regression in Spss or Excel.
You have to evaluate the measurement model as well as the structural model (your hypothesized correlations). The path coefficients in PLS are the same as regression coefficients. With the bootstrap method you can calculate t-values for you paths.
See this forum and the working papers by Ringle on the measures that help you determine how well your model fits the data. The site by Prof. W.Chin should also be of good use (just google for "chin pls" )
I hope this helps
Philipp
Hello Philipp,
thanks for your answer. Maybe I have´t been detailled enough... ;-)
Mostly I use PLS for my structural model to interprete different paths from some exogenous vaiables to endogenous variables. This is one side of my thesis and this works already well including the interpretation (weights, loadings, t-test, etc.)
In addition to that I want to check some correlations as I described in my first posting. I have to check three of my endogenous variables (formative and reflective) if they are correlated and if the correlation is significant. Maybei anybody has got an idea...
Thanks a lot
Michael
thanks for your answer. Maybe I have´t been detailled enough... ;-)
Mostly I use PLS for my structural model to interprete different paths from some exogenous vaiables to endogenous variables. This is one side of my thesis and this works already well including the interpretation (weights, loadings, t-test, etc.)
In addition to that I want to check some correlations as I described in my first posting. I have to check three of my endogenous variables (formative and reflective) if they are correlated and if the correlation is significant. Maybei anybody has got an idea...
Thanks a lot
Michael
- Diogenes
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Hi Michael,
you could copy/paste the LV scores to SPSS and compute the correlations and significances there.
Or to use a resampling software http://www.uvm.edu/~dhowell/StatPages/R ... pling.html
Best regards.
Bido
you could copy/paste the LV scores to SPSS and compute the correlations and significances there.
Or to use a resampling software http://www.uvm.edu/~dhowell/StatPages/R ... pling.html
Best regards.
Bido
Hello Prof. Diogenes,
thanks for your answer.
Copy and paste doesn't make sense, does it? As I know, it is only possible to test correlations beetween two variables/indicators, either? Also the link, you have pasted, seems to analyse the correlation beetween two indicators.
In my specific case I have to test the correlation beetween two latent constructs (with several indicators) and find an answer, if the correlation is significant or not.
Best wishes
Michael
thanks for your answer.
Copy and paste doesn't make sense, does it? As I know, it is only possible to test correlations beetween two variables/indicators, either? Also the link, you have pasted, seems to analyse the correlation beetween two indicators.
In my specific case I have to test the correlation beetween two latent constructs (with several indicators) and find an answer, if the correlation is significant or not.
Best wishes
Michael
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path correlations
If you want to check correlation significances between constructs, use spss and check out correlation between factor scores of the constructs.
A hypothesis is an arrow in the diagram. Check it out first.
A hypothesis is an arrow in the diagram. Check it out first.
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Hi Vivek,
just one last remembering.
For instance, If we have two LV without arrows between them:
- in LISREL will be imposed during the estimation that the partial correlation be zero between them(a constrain);
- in PLS, all LV are correlated, even without arrows (no constrain). This is not tested, for this reason Michael asked us.
Best regards.
Bido
just one last remembering.
For instance, If we have two LV without arrows between them:
- in LISREL will be imposed during the estimation that the partial correlation be zero between them(a constrain);
- in PLS, all LV are correlated, even without arrows (no constrain). This is not tested, for this reason Michael asked us.
Best regards.
Bido
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- Location: Coimbatore, India
LV correlations
True Prof Bido. We check the discriminant validity in LISREL by seeing the increase in chi square value after imposing a correlation of 1 between the constructs.
By the way thanks for all your timely help. I have submitted my dissertation on supply chains.
Regards
Vivek
By the way thanks for all your timely help. I have submitted my dissertation on supply chains.
Regards
Vivek