Dear all,
Do the Sargan and Hansen J tests only apply if one has more IVs than endogenous regressors? These are overidentification tests, right?
How can I check if the IV violates the exclusion restriction is violated if there is only one IV and one endogenous regressor? No way I can show this is the case, right?
If I have doubts about whether my IV meets the exclusion restriction AND I have concerns about endogeneity...shall I "believe" the OLS estimates or shall I "believe" the 2SLS ones...Or probably none?
thanks
Happy holidays to all.
Carola
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