Admissible Invariant Similar Tests for Instrumental Variables Regression
21 Pages Posted: 3 Apr 2007
Date Written: March 12, 2007
This paper studies a model widely used in the weak instruments literature and establishes admissibility of the weighted average power likelihood ratio tests recently derived by Andrews, Moreira, and Stock (2004). The class of tests covered by this admissibility result contains the Anderson and Rubin (1949) test. Thus, there is no conventional statistical sense in which the Anderson and Rubin (1949) test "wastes degrees of freedom". In addition, it is shown that the test proposed by Moreira (2003) belongs to the closure of (i.e., can be interpreted as a limiting case of) the class of tests covered by our admissibility result.
Keywords: Instrumental Variables, Regression, Inference
JEL Classification: C13, C14, C30, C51, D4, J24, J31
Suggested Citation: Suggested Citation