This post is on robust RMSEA, a follow-up to a previous post on robust CFI:
To my understanding, how the robust RMSEA, if printed, is computed depends on several factors, just like robust CFI. There are not one, but several, versions of robust RMSEA in the printout of lavaan output.
In teaching, I would like to provide the reference for a measure whenever possible. Therefore, I am trying to summarize my understanding, based on
the version history and posts I located here, and the source code, to find the correct reference for each version of robust RMSEA.
This is what I recovered so far. (I used a format similar to the one I used in the previous post.)
First, if any of these is in `test` (see lavOptions), robust RMSEA will be printed
- "satorra.bentler", "yuan.bentler.mplus", "yuan.bentler", "scaled.shifted". (This part is not important because this is usually determined by the estimator users used. Users rarely set this option directly.)
How robust RMSEA is computed will then be determined by these steps:
1) If all variables are categorical, the formula proposed by Savalei (2021) will be used. (Equation 6a).
2) If not all variables are categorical but FIML is used for missing data, then Zhang and Savalei (2022) will be used.
2a) If scaled test statistics are requested for nonnormal data, V3 (version 3) is used
2b) If scaled test statistics are not requested, V6 (Version 6) is used.
3) If not all variables are categorical and FIML is not used, then
3a) If "scaled.shifted" is in test, then Savalei (2018) will be used. (Eq 7?)
3b)
If "scaled.shifted" is not in test, then
Brosseau-Liard and Savalei (2012) is used. (Eq. 9?)
I did not use MLM, MLMV, etc. because they are shorthand to set other options. It is more precise, to me, to use the factors above.
I am not 100% certain about my understanding and so I share the summary here. Please correct any mistakes I made. Please also feel free to suggest any better ways to present how robust RMSEA is computed in lavaan.
Thanks.
-- Shu Fai
Brosseau-Liard, P. E., Savalei, V., & Li, L. (2012). An investigation of the sample performance of two nonnormality corrections for RMSEA.
Multivariate Behavioral Research, 47(6), 904–930.
https://doi.org/10.1080/00273171.2012.715252
Savalei, V. (2018). On the computation of the RMSEA and CFI from
the mean-and-variance corrected test statistic with nonnormal data in
SEM.
Multivariate Behavioral Research,
53(3), 419–429.
https://doi.org/10.1080/00273171.2018.1455142
Zhang, X., & Savalei, V. (2022). New computations for RMSEA and CFI following FIML and TS estimation with missing data.
Psychological Methods.
https://doi.org/10.1037/met0000445