What does it mean if running xtreg but resulting missing Wald chi2?

[Phuc Nguyen]

I have a regression using xtreg with the results like that

I am wondering what do Wald chi2(10) and Prob>chi2 missing above mean? Can the regression results can be used?

[Carlo Lazzaro]

Phuc:
did you invoke non-default standard errors?

[Phuc Nguyen]

Phuc:
did you invoke non-default standard errors?

Sorry, I did nt get your point, Carlo Lazzaro , I just run a normal xtreg with controlling time fixed effect and clustering by units

[Carlo Lazzaro]

Phuc:
if you used clustered-robust standard errors, you may want to take a look at -help j_robustsingular-.
Please consider that my reply is conditional on the (deprecated on this list for technical reasons) screenshot that you posted and that, as per FAQ, should be replaced by your code and Stata results embedded within CODE delimiters. Thanks.