The primary concern of this article is the provision of definitions and tests for exogeneity appropriate for models defined through sets of conditional moment restrictions. These forms of exogeneity are expressed as additional conditional moment constraints and may be equivalently formulated as...

We develop a new specification test for the IV estimators adopting a particular second order approximation of Bekker (1994). The new specification test compares the difference of the forward (conventional) 2SLS estimator of the coefficient of the right hand side endogenous variable with the...

We develop a new specification test for IV estimators adopting a particular second order approximation of Bekker. The new specification test compares the difference of the forward (conventional) 2SLS estimator of the coefficient of the right-hand side endogenous variable with the reverse 2SLS...