Spmatrix: variable does not uniquely identify observations in the master data

[Jason Liang]

just typed a command below to create spacial matrix

spmatrix create contiguity bW

and it turned out that variable _ID does not uniquely identify observations in the master data.
I wonder how this situation occurred? Thanks to anyone reaching out..

[Andrew Musau]

Do you have panel data? If so, see #5 of https://www.statalist.org/forums/for...ate-contiguity and the referenced documentation.