Invariant tests in an instrumental variables model with unknown data generating process

• Ano de defesa: 2015
• Autor(a) principal: Castro, Gustavo Rabello de
• Orientador(a): Moreira, Marcelo Jovita
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Palavras-chave em Português: Regressão com variáveis instrumentais; Testes invariantes; Testes ótimos; Testes similares; Testes não viesados; Instrumentos fracos
• Palavras-chave em Inglês: Instrumental variable regression; Invariant tests; Optimal tests; Similar tests; Unbiased tests; Weighted average power tests; Weak instruments
• Link de acesso: https://hdl.handle.net/10438/15228

In this work we focus on tests for the parameter of an endogenous variable in a weakly identi ed instrumental variable regressionmodel. We propose a new unbiasedness restriction for weighted average power (WAP) tests introduced by Moreira and Moreira (2013). This new boundary condition is motivated by the score e ciency under strong identi cation. It allows reducing computational costs of WAP tests by replacing the strongly unbiased condition. This latter restriction imposes, under the null hypothesis, the test to be uncorrelated to a given statistic with dimension given by the number of instruments. The new proposed boundary condition only imposes the test to be uncorrelated to a linear combination of the statistic. WAP tests under both restrictions to perform similarly numerically. We apply the di erent tests discussed to an empirical example. Using data from Yogo (2004), we assess the e ect of weak instruments on the estimation of the elasticity of inter-temporal substitution of a CCAPM model.