Usage of Rho_A reliability coefficient

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Brusset_X
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Usage of Rho_A reliability coefficient

Post by Brusset_X » Wed Feb 24, 2016 7:33 pm

Hi everyone,
I would like to use the rho_A coefficient as defined in Dijkstra and Henseler(2015) and implemented in PLS3.2.
In a small model with 4 reflexive constructs, I have both rho_A and sqrt(rho_A) in the tables as implemented by PLS3.2. The above reference does not give an idea of the threshold under which a rho_A indicates that a LV is not reliable. And what use does sqrt(Rho_A) have?

One key LV which is causing me headaches has 8 items, a Cronbach alpha of .705, a composite reliability of 0=.403 and a rho_A of .647. How do I analyze such results? Pruning the items only makes things worse (at least regarding the alpha).

All path coefficients leading from it are t-statistics <1.96, meaning that it does not have any effect on the other LV.
BTW, all the other LV have nice and healthy reliability and discriminating coefficients.

Any help appreciated.
Thanks.
Xavier Brusset
Professor
Logistics and supply chain management
Toulouse Business School

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Hengkov
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Re: Usage of Rho_A reliability coefficient

Post by Hengkov » Sat Feb 27, 2016 9:18 am

Hi Xavier,

That I remember the cut-off value of coefficient Dijkstra-Henseler Rho_A must be > 0.7 as Composite Reliability.
If you do not want to remove the item, you may have to give a little justification there.

You also need to see the value GoF with SRMR and NFI, I think you are a bit of a bad fit model.

Best regards,

jmbecker
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Re: Usage of Rho_A reliability coefficient

Post by jmbecker » Thu Mar 03, 2016 9:15 pm

Hi Latan,
can you provide a reference that explains how to calculate the NFI for PLS models?
Dr. Jan-Michael Becker, University of Cologne, SmartPLS Developer
Researchgate: https://www.researchgate.net/profile/Ja ... v=hdr_xprf
GoogleScholar: http://scholar.google.de/citations?user ... AAAJ&hl=de

Brusset_X
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Re: Usage of Rho_A reliability coefficient

Post by Brusset_X » Tue Mar 22, 2016 1:52 pm

Hi Latan,
Thank you for the reply. I have looked at the Dijkstra Henseler reference and they don't mention a cut-off value for Rho_A. If I look at the SRMR given by SmartPLS3.2.3, I get a SRMR for common factor of 0.079 and SRMR for the composite model of 0.053. Are these good values?

Would you mind giving a reference on how to evaluate these criteria for model fit? Also, you speak of NFI. I thought that NFI was purely for SEM-ML models, ie, LISREL AMOS type models.

Can you please substantiate how such an index can be calculated in PLS?

Thank you for your time and patience.

Regards.
Xavier
Xavier Brusset
Professor
Logistics and supply chain management
Toulouse Business School

lpfeil
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Re: Usage of Rho_A reliability coefficient

Post by lpfeil » Wed Jul 04, 2018 10:56 am

Hi everyone,

Does anybody know what a Rho_A value above 1 means and how to interpret it?

Best regards,

Lisa

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