cross section independence tests- error

[shewali gupta]

Hi total no. of observations are 525 and groups 35, while performing pesaran and freidman test for cross section dependence, i am getting errors like xtcsd, pesaran

Pesaran's test of cross sectional independence = ., Pr = . and xtcsd, friedman

Friedman's test of cross sectional independence = ., Pr = .
Kindly help, there are no missing values.