Dear forum,

I have a basic doubts of methodology for which many of you may know the answer.

I am using seemingly unrelated regression (sureg) to test the following model:
sureg breadthn2005 c.approp2005##c.approp2005 int_rd2005 grupo2005 size2005 inci12005 market_size2005

As an example of a paper that report results after applying sureg I am following the following article: Laursen, K., & Salter, A. J. (2014). The paradox of openness: Appropriability, external search and collaboration. Research policy, 43(5), 867-878.

In their table of results, they report ML (Cox-Snell) R2. However, when checking the information provided in the manual of Stata about the sureg sintax, I could not find information about which type of pseudo R2 is provided by the program after using sureg.

By searching in the stata forum I found that “fitstat” is a post-estimation command that computes a variety of measures of fit for many kinds of regression models. However, this command does not work after suing sureg so I cannot use it to obtain the ML (Cox-Snell) R2.

My question, is there any command I can use to obtain the ML (Cox-Snell) R2 after using sureg?

Also, I would like to ask, How can I interpret low values of ML (Cox-Snell) R2? Can it be interpreted as one would interpret an OLS R-squared?

Thank you very much in advance for the help .