Inference in Structural Vector Autoregressions when the Identifying Assumptions are not Fully Believed: Re-evaluating the Role of Monetary Policy in Economic Fluctuations
Journal of Monetary Economics,
Point estimates and error bands for SVARs that are set identified are only justified if the researcher is persuaded that some parameter values are a priori more plausible than others. When such prior information exists, traditional approaches can be generalized to allow for doubts about the identifying assumptions. We use information about both structural coefficients and impacts of shocks and propose a new asymmetric t-distribution for incorporating information about signs in a nondogmatic way. We apply these methods to a three-variable macroeconomic model and conclude that monetary policy shocks are not the major driver of output, inflation, or interest rates.
Banks Fearing the Drought? Liquidity Hoarding as a Response to Idiosyncratic Interbank Funding Dry-ups
IWH Discussion Papers,
Since the global financial crisis, economic literature has highlighted banks’ inclination to bolster up their liquid asset positions once the aggregate interbank funding market experiences a dry-up. To this regard, we show that liquidity hoarding and its detrimental effects on credit can also be triggered by idiosyncratic, i.e. bankspecific, interbank funding shocks with implications for monetary policy. Combining a unique data set of the Brazilian banking sector with a novel identification strategy enables us to overcome previous limitations for studying this phenomenon as a bankspecific event. This strategy further helps us to analyse how disruptions in the bank headquarters’ interbank market can lead to liquidity and lending adjustments at the regional bank branch level. From the perspective of the policy maker, understanding this market-to-market spillover effect is important as local bank branch markets are characterised by market concentration and relationship lending.
Skills, Earnings, and Employment: Exploring Causality in the Estimation of Returns to Skills
Large-scale Assessments in Education,
Ample evidence indicates that a person’s human capital is important for success on the labor market in terms of both wages and employment prospects. However, unlike the efforts to identify the impact of school attainment on labor-market outcomes, the literature on returns to cognitive skills has not yet provided convincing evidence that the estimated returns can be causally interpreted. Using the PIAAC Survey of Adult Skills, this paper explores several approaches that aim to address potential threats to causal identification of returns to skills, in terms of both higher wages and better employment chances. We address measurement error by exploiting the fact that PIAAC measures skills in several domains. Furthermore, we estimate instrumental-variable models that use skill variation stemming from school attainment and parental education to circumvent reverse causation. Results show a strikingly similar pattern across the diverse set of countries in our sample. In fact, the instrumental-variable estimates are consistently larger than those found in standard least-squares estimations. The same is true in two “natural experiments,” one of which exploits variation in skills from changes in compulsory-schooling laws across U.S. states. The other one identifies technologically induced variation in broadband Internet availability that gives rise to variation in ICT skills across German municipalities. Together, the results suggest that least-squares estimates may provide a lower bound of the true returns to skills in the labor market.
Sign Restrictions, Structural Vector Autoregressions, and Useful Prior Information
This paper makes the following original contributions to the literature. (i) We develop a simpler analytical characterization and numerical algorithm for Bayesian inference in structural vector autoregressions (VARs) that can be used for models that are overidentified, just‐identified, or underidentified. (ii) We analyze the asymptotic properties of Bayesian inference and show that in the underidentified case, the asymptotic posterior distribution of contemporaneous coefficients in an n‐variable VAR is confined to the set of values that orthogonalize the population variance–covariance matrix of ordinary least squares residuals, with the height of the posterior proportional to the height of the prior at any point within that set. For example, in a bivariate VAR for supply and demand identified solely by sign restrictions, if the population correlation between the VAR residuals is positive, then even if one has available an infinite sample of data, any inference about the demand elasticity is coming exclusively from the prior distribution. (iii) We provide analytical characterizations of the informative prior distributions for impulse‐response functions that are implicit in the traditional sign‐restriction approach to VARs, and we note, as a special case of result (ii), that the influence of these priors does not vanish asymptotically. (iv) We illustrate how Bayesian inference with informative priors can be both a strict generalization and an unambiguous improvement over frequentist inference in just‐identified models. (v) We propose that researchers need to explicitly acknowledge and defend the role of prior beliefs in influencing structural conclusions and we illustrate how this could be done using a simple model of the U.S. labor market.
The Causal Effect of Watching TV on Material Aspirations: Evidence from the “Valley of the Innocent”
Journal of Economic Behavior and Organization,
The paper addresses the question of whether TV consumption has an impact on material aspirations. We exploit a natural experiment that took place during the period in which Germany was divided. Owing to geographical reasons TV programs from the Federal Republic of Germany could not be received in all parts of the German Democratic Republic. Therefore a natural variation occurred in exposure to West German television. We find robust evidence that watching TV is positively correlated with aspirations. Our identification strategy implies a causal relationship running from TV to aspirations. This conclusion resists various sets of alternative specifications and samples.
Cartel Identification in Spatial Markets: An Analysis of the East German Cement Market
Jahrbuch für Regionalwissenschaft,
In 2003, the German cement industry was fined more than six hundred million Euros for, allegedly, having fixed prices and quantities in the four regional German cement markets. When this case was finally resolved by the courts in 2009, the fine was reduced by a large amount as the German Antitrust Commission (GAC) was unable to provide sufficient evidence on the level excessive pricing by the cartelists.
This paper takes up again the case of the East German cement cartel that ended in early 2002 and shows that the quota agreement which was established in the mid 1990s was economically inactive. From the perspective of the individual players, the rationale of preserving the cartel can only be explained by limited knowledge of the true market forces. Based on a spatial approach for the years 1997 to 2002, the regional price-setting behavior and its changes can be analyzed against the situation. Econometric analysis suggests that competition was already rather strong in the cartel years as transport costs and rebate systems were used to fine-tune offers. Strategic imports from post-communist countries into the East German market as well as supply from medium-sized enterprises not included in the cartel exerted pressure on the markets.