near singular

[startz]

The command

Code: Select all

ls grade_num @expand(course_dept_code)

works for an unstructured file. When I turn the file into a panel with a different variable for the id, I get nonsingular matrix.

Uh, what's going on?

[EViews Gareth]

Can you provide the file?

[startz]

I can't, as it's confidential. Is there something you want me to do to shed light on the issue?

[EViews Gareth]

Without seeing it is hard to be certain, but at a guess it is knifeedge singular. Panel LS goes through a slightly different calculation routine, and I’d guess they differ in triggering singular

[startz]

Without seeing it is hard to be certain, but at a guess it is knifeedge singular. Panel LS goes through a slightly different calculation routine, and I’d guess they differ in triggering singular

I would understand that if it weren't @expand. What can be multicollinear with a set of dummy variables?