Market concentration and the likelihood of financial crises

According to theory, market concentration affects the likelihood of a financial crisis in different ways. The “concentration-stability” and the “concentration-fragility” hypotheses suggest opposing effects operating through specific channels. Using data of 160 countries for the period 1970–2009, this paper empirically tests these indirect effects of financial market structure. We set up a simultaneous system in order to jointly estimate financial stability and the relevant channel variables as endogenous variables. Our findings provide support for the assumption of channel effects in general and both the concentration-stability and the concentration-fragility hypothesis in particular. The effects are found to vary between high and low income countries.     

A note on the consistency of maximum likelihood estimators

Abstract

A sequence of maximum likelihood estimators based on a sequence of independent but not necessarily identically distributed random variables is shown to be consistent under certain assumptions. Some examples are given to show that these assumptions are easy to verify and not very restrictive.     

The distribution of earnings relative to targets in the European Union

This paper provides evidence on the distribution of reported earnings relative to targets in the Member States of the European Union (EU). For a large sample of over 60,000 firm-years between 1986 and 2001, we find that more firms than expected (i) report small positive earnings, (ii) report small positive earnings changes and (iii) have zero or small positive forecast errors. These discontinuities are much more pronounced in the EU compared to the US, and the distributions of reported earnings and earnings changes are characterised by lower dispersion and more clustering around zero, consistent with higher income smoothing in Europe. Across the EU, we find that the avoidance of a loss or an earnings decrease is more common in those Member States which do not have a long history of accounting standard setting, and particularly in those which, until recently, were almost entirely law-based. The earnings distributions and earnings change distributions of UK firms resemble more those of their counterparts in the US. and differ from the rest of the EU. despite the various EU harmonisation efforts that have taken place.     

The likelihood ratio test statistic of mean-variance efficiency without a riskless asset

The question whether a given porfolio is mean-variance efficient is a basic problem of investment analysis. Mean-variance efficiency is also the basis of the Capital Asset Pricing Model. This paper presents the explicit form of the likelihood ratio test of the hypothesis that a given portfolio, or a particular market index, is ex-ante mean-variance efficient in the case where there is no riskless asset. Geometric relations are illustrated to provide intuition about the constrained maximum likelihood estimators and the test statistic, and two simple economic interpretations of the test are given.     

The search for relative value in bonds

Comparing asset swap spreads across bonds is a widely used tool for measuring relative value. This approach leads portfolio managers to increase their risk exposure in ways that are not transparent. Credit default swaps are utilized to demonstrate that viewing wide asset swaps as an indicator of relative value is a mirage. The paper documents the empirical regularities in the term structure of credit spreads and spread volatilities that make this result possible. In addition, we present empirical evidence of the imprint made on corporate bond returns by the widespread use of the asset swaps data.     

Maximum likelihood estimation of stochastic volatility models

We develop and implement a method for maximum likelihood estimation in closed-form of stochastic volatility models. Using Monte Carlo simulations, we compare a full likelihood procedure, where an option price is inverted into the unobservable volatility state, to an approximate likelihood procedure where the volatility state is replaced by proxies based on the implied volatility of a short-dated at-the-money option. The approximation results in a small loss of accuracy relative to the standard errors due to sampling noise. We apply this method to market prices of index options for several stochastic volatility models, and compare the characteristics of the estimated models. The evidence for a general CEV model, which nests both the affine Heston model and a GARCH model, suggests that the elasticity of variance of volatility lies between that assumed by the two nested models.     

The great increase in relative wage volatility in the United States

Over the past 25 years, real average hourly wages in the United States have become substantially more volatile relative to output. Microdata from the Current Population Survey (CPS) is used to show that this increase in relative volatility is predominantly due to increases in the relative volatility of hourly wages across different groups of workers. Compositional changes of the workforce, by contrast, account for only a small fraction of the increase in relative wage volatility. Simulations with a Dynamic Stochastic General Equilibrium (DSGE) model illustrate that the observed increase in relative wage volatility is unlikely to come from changes outside of the labor market (e.g. smaller exogenous shocks or more aggressive monetary policy). By contrast, greater flexibility in wage setting due to deunionization and a shift towards performance-pay contracts as experienced by the U.S. labor market is capable of accounting for a substantial fraction of the observed increase in relative wage volatility. Greater wage flexibility also decreases the magnitude of business cycle fluctuations, suggesting an interesting new explanation for the Great Moderation.     

Maximum likelihood estimation of non-affine volatility processes

In this paper we develop a new estimation method for extracting non-affine latent stochastic volatility and risk premia from measures of model-free realized and risk-neutral integrated volatility. We estimate non-affine models with nonlinear drift and constant elasticity of variance and we compare them to the popular square-root stochastic volatility model. Our empirical findings are: (1) the square-root model is misspecified; (2) the inclusion of constant elasticity of variance and nonlinear drift captures stylized facts of volatility dynamics and (3) the square-root stochastic volatility model is explosive under the risk-neutral probability measure.     

The asymptotic relative efficiencies of tests and the derivatives of their power functions

Abstract

For comparing two consistent tests of a simple null hypothesis H ₀ : θ = θ₀ against a given alternative hypothesis H ₀ : θ = θ₁, the measure most frequently used is the asymptotic relative efficiency (ARE), due to Pitman (1948). The ARE is defined as the limit of the reciprocal of the ratio of sample sizes required to attain the same power. The limit is taken as sample sizes tend to infinity and simultaneously θ₁ → θ₀, this being necessary to keep the powers of the tests bounded away from 1.     

在劳动竞赛中确立劳模品牌的地位与作用

劳动竞赛是基层支行为冲刺某项任务目标常用的一种激励手法。通常意义上，组织者看重的是有形竞赛的阶段性效应，很少有从劳模品牌的角度去开拓无形竞赛的长效机制，因而，时有劳动竞赛流于形式的现象发生。在当前新的形势下，我们有必要抓住劳模品牌在劳动竞赛中的核心作用，锤炼和升华伟大的劳模精神，以高度的主人翁精神，博大的全局胸怀，强烈的开拓意识和忘我的劳动热情，创造和开发出平凡而又震撼人心的劳模品牌。     

An examination of the relative economic efficiency of mutual vs. stock savings institutions

This article employs a nonlinear system of Cobb-Douglas profit and input demand equations to analyze price and technical efficiency in a sample of presumably not-for-profit mutual and presumably profit-maximizing stock savings institutions. Theories of property rights and agency are reviewed to provide predictions of price efficiency (i.e., profit maximization and cost minimization behavior), and technical efficiency. The study makes several contributions to the literature. First, it examines the effect of ownership form on both price and technical efficiency. Second, it separately examines the effect of regulatory form on both price and technical efficiency. The model enables us to analyze the separate effects of ownership and regulatory form across a heterogeneous sample of firms. We also analyze the effects of risk in the form of two separate regulatory variables and the effect of market share on economic efficiency.