Yes, in the manuscript (Jankovic et al, 2014) they do not give a reference when they mentioned "RRR requires a reasonable sample size for an appropriate examination". I saw some researchers discussed the topic "Small sample size in PLS - any thoughts?" in a post (https://www.researchgate.net/post/Small_sample_size_in_PLS-any_thoughts). So I have this question.   As both PLS and RRR could explain the relationship between X (X1 to Xn) with Y (Y1 to Yn'). For example, in RRR, the X1 to X20 are set as continuous variables rather than classific variables, and the Y1 to Y6 are also set as continuous variables. So the X1 to X20 will be explained by the dietary pattern (less than the 6 types).  According to your suggestion, is the number of effects 20? or 26? ——and If according to the “Mansour Zarra-Nezhad” who give a formula in the post above, |10 multiplied by the maximum number of indicators of a latent variable", is it ok? ... View more

I think your words for a long time. I still have a few puzzles. For example, I want to do the same thing as the linked paper which used the RRR method. It has big samples. https://doi.org/10.3390/nu14050980 I saw another paper that also used the RRR method but with smaller samples ( https://doi.org/10.1186/1475-2891-13-30 ). Well, my sample is smaller than that. ... View more

I want to use a previous dietary data to build a dietary mode firstly. For example, X are 20 kind groups of food intake. Y are the target nutrients intake, energy density and so on. After geting the xloading then applying this xloading into a new dietary data (which divided their food in same 20 kind group). You know the process to connect the xloading with intake of food group in new data to get dietary factor scores. Then to divide the dietary factor scores based on quintile and set them as independent variables to bulid regression models. In these examples, disease situation also be set as outcome variable. We want to explore the relationship between the dietary mode (dietary factor scores quintile group) with the disease. (the relationship could also be used to predict in some situation) ... View more

Thank you very much for your examples and link! ... View more

@PaigeMiller Thank you very much! I want to use the RRR in Proc Pls to build dietary model. That might be a better choice to use RRR if want to get a better scores of dependent variables. Am I right? While, I know the the SAS give an example of cross validation when use method=PLS. Does it work when I use method=RRR? ... View more

@Rick_SAS Thank you very much! I will think about this! ... View more

Thank you for your reply! I will try! Thank you! ... View more

Thank you very much! I will learn about what you suggest and try. ... View more

Is anyone could help me? ... View more

Yes, the Relative risk in table 6 were calculated by logistic model (a new model) not from RRR. This paper might use the scores as a independent variable in the new logistic model. I figured out my problems. Thank you so much for your help! ... View more

Thank you very much, Paige! First, I think the author use the  "factor scores"  as  a new dependent variablesIs，and a new health outcome as dependent variable to build a new regression model. This regression is not the previous regression by RRR method as the dependent variable changed, so the previous "Parameter Estimates" of response variables was not matching. It is a new exploring.   Back to the original problem: (1) I know each extracted factor (Factor 1……) in RRR have one fixed parameter of every independent variable (eg. "ab1……"，also like the different food in table 8） or dependent variable (eg. "b c d e" in my code) .  so it could be create a "scores", such as "xscore"、“yscore” we have output.     So my question is whether the "factor scores"  here in the table 6 is the output column of  "xscore" or the "yscore"?   （2）If it is "xscore"——could we calculate the "xscore" through multiply-accumulate of independent variables and their "model Effect Loadings" (name was according to the RRR results) ?   for example:     ab1 * “model effect Loadings of ab1” + ab2 * “model Effect Loadings of ab2” +…… ... View more

Thank you for your reply at this time! it is night, you are so kind! I compared the yweights, it is the "Dependent Variable Weights" if I add the "details" option. it that the Response score coefficients? ... View more

I have the same problems in using RRR. I have read the a published paper（https://doi.org/10.1093/aje/kwh134） which used RRR to find a dietary mode. In that paper, the author gave many results obtained by RRR （as follows）. 1、In table 5, it gave the “Response score coefficient”  2、in table 8, it gave the "Standardized score parameter 、Correlation with score"   but I have no idea how to obtain them or what are their names  in the RRR results if using the following code. Could you help me? proc pls data=abc method=RRR nfac=4 varss details; model b c d e = ab1-ab10/SOLUTION ; output out=pattern xscore=scorex yscore=scorey; run;   In the results, it will show "Model Effect Loadings"、"Model Effect Weights"、"Dependent Variable Weights"、"Coded Regression Coefficients for 4 Extracted Factors" and "Parameter Estimates".   Which one is the “Response score coefficient”  in table 5 (the picture above)? Which one is the "Standardized score parameter 、Correlation with score" in the table 8 (the picture above)?   3、in this paper in table 6, the factor scores from RRR were used as the independent variable to build a new regression. I thought is was ok. Is the "factor scores" in the table 6 means the output values of  "xscore" column (as in my sas code)? Why I asked this, because I saw your doubt about in another reply. Some one want to use the factor scores to build a regression. Are they same things? Could we?  Sorry for ask the questions here instead of starting a new post! Just I hope you could see it or some one who know the answers could help me! Thank you so much! ... View more