When the overidentifying restrictions of the constant-effect linear instrumental variables model fail, common IV estimators converge to different probability limits. I characterize the estimands of two stage least squares, two step GMM, and limited information maximum likelihood as functions of the single-instrument estimands from the just-identified IV regressions which consider each instrumen...

In this paper we test for the inclusion of the bid-ask spread in the consumption CAPM, in the UK stock market over the time period of 1980-2000. Two econometric models are used; first, Fisher’s (1994) asset pricing model is estimated by GMM, and secondly, the VAR approach proposed by Campbell and Shiller is extended to include the bid-ask spread. Overall the statistical tests are unable to reje...

This paper derives a model of maintenance and repair expenses from an analytical framework based on rational economic behavior in which maintenance, utilization and service life are appropriately integrated and estimates it with the help of data from 433 automobiles imported into Greece from various countries. On the theoretical plain it is shown that the model allows endogenously for most of t...

1 This paper provides a first order asymptotic theory for generalized method of moments (GMM) estimators when the number of moment conditions is allowed to increase with the sample size and the moment conditions may be weak. Examples in which these asymptotics are relevant include instrumental variable (IV) estimation with many (possibly weak or uninformed) instruments and some panel data model...

We analyze the limiting distribution of Rivers and Vuong’s (2002) statistic for choosing between two competing dynamic models based on a comparison of GMM minimands. It is shown that: (i) if both models are misspecified then the statistic has a standard normal distribution under the null hypothesis of equal fit but the ranking could be determined by the choice of the weighting matrix; (ii) if b...

This paper tests whether consumption pattern in Korea exhibits a time-inconsistent discounting behavior using a quasi-hyperbolic Euler equation estimated by the generalized method of moments (GMM). In particular, we examine whether consumers change their discounting behavior during financial crises in 1997 and 2008. The estimation results show that Korean consumers exhibit a time-inconsistent q...

Measurement error causes a downward bias when estimating a panel data linear regression model. The panel data context offers various opportunities to derive moment conditions that result in consistent GMM estimators. We consider three sources of moment conditions: (i) restrictions on the intertemporal covariance matrix of the errors in the equations, (ii) heteroskedasticity and nonlinearity in ...

Following the present atmosphere of budgetary cuts we analyze the effects of fiscal consolidation on the composition of government expenditures by functions. Using a dynamic voter group decision model and exploiting the panel structure of the dataset – 26 OECD countries over the period 1970-1997by GMM estimation we find that fiscal adjustments protect social expenditure. Nevertheless, we find t...

In models with potential weak identification researchers often decide whether to report a robust confidence set based on an initial assessment of model identification. Two-step procedures of this sort can generate large coverage distortions for reported confidence sets, and existing procedures for controlling these distortions are quite limited. This paper introduces a generally-applicable appr...

Social sanctions may be a strong deterrent of crime. This paper presents a formal model that relates crime and social sanction to social interaction density. We empirically test the theoretical predictions using a provincial level panel dataset on different crimes in Italy between 1996 and 2003. We exploit detailed demographic and geo-morphological information to develop exogenous measures of s...