Template-Type: ReDIF-Paper 1.0 Author-Name: Gary Koop Author-Name-First: Gary Author-Name-Last: Koop Author-Email: gary.koop@strath.ac.uk Author-Workplace-Name: Department of Economics, University of Strathclyde Author-Name: Roberto Leon-Gonzalez Author-Name-First: Roberto Author-Name-Last: Leon-Gonzalez Author-Email: rlg@grips.ac.jp. Author-Workplace-Name: National Graduate Institute for Policy Studies Author-Name: Rodney Strachan Author-Name-First: Rodney Author-Name-Last: Strachan Author-Email: rodney.strachan@anu.edu.au Author-Workplace-Name: The Australian National University Title: Bayesian Model Averaging in the Instrumental Variable Regression Model* Abstract: This paper considers the instrumental variable regression model when there is uncertainty about the set of instruments, exogeneity restrictions, the validity of identifying restrictions and the set of exogenous regressors. This uncertainty can result in a huge number of models. To avoid statistical problems associated with standard model selection procedures, we develop a reversible jump Markov chain Monte Carlo algorithm that allows us to do Bayesian model averaging. The algorithm is very ?exible and can be easily adapted to analyze any of the di¤erent priors that have been proposed in the Bayesian instrumental variables literature. We show how to calculate the probability of any relevant restriction (e.g. the posterior probability that over-identifying restrictions hold) and discuss diagnostic checking using the posterior distribution of discrepancy vectors. We illustrate our methods in a returns-to-schooling application. Length: 49 pages Creation-Date: 2011-04 Revision-Date: Publication-Status: File-URL: http://www.strath.ac.uk/media/1newwebsite/departmentsubject/economics/research/researchdiscussionpapers/2011/11-12_Final.pdf File-Format: Application/pdf Number: 1112 Classification-JEL: FC11, C30 Keywords: Bayesian, endogeneity, simultaneous equations, reversible jump Markov chain Monte Carlo. Handle: RePEc:str:wpaper:1112