Portfolio optimization using dynamic factor and stochastic volatility: evidence on Fat‐tailed errors and leverage

The portfolio optimization problem is investigated using a multivariate stochastic volatility model with factor dynamics, fat‐tailed errors and leverage effects. The efficient Markov chain Monte Carlo method is used to estimate model parameters, and the Rao–Blackwellized auxiliary particle filter is used to compute the likelihood and to predict conditional means and covariances. The proposed models are applied to sector indices of the Tokyo Stock Price Index (TOPIX), which consists of 33 stock market indices classified by industrial sectors. The portfolio is dynamically optimized under several expected utilities and two additional static strategies are considered as benchmarks. An extensive empirical study indicates that our proposed dynamic factor model with leverage or fat‐tailed errors significantly improves the predictions of the conditional mean and covariances, as well as various measures of portfolio performance.     

Modelling European sovereign bond yields with international portfolio effects

This paper proposes a portfolio choice model with two countries to evaluate the specific role of volatility and co-volatility risks in the formation of long-term European interest rates over the crisis and post-crisis periods with an active role of the European Central Bank. Long-term equilibrium rates depend crucially on the covariances between international bond yields anticipated by investors. Positively anticipated covariances amplify the phenomena of fundamental contagions related to the degradations of public finance and solvency of sovereign debt issuer, while negatively anticipated covariances amplify the phenomena of Flight-to-quality. The two-step econometric approach over the period January 2006 to September 2016 analyses 21 European market pairs in a bivariate GARCH framework. Empirical results show that the decline in German and French long-term rates from March 2011 is partially due to the decrease in both risk premium and covariances with periphery countries. These declines actually amplify the mechanisms of Flight-to-quality. Finally, a lower sensitivity of rate to volatility and co-volatility risks during the crisis period gives credit to the hypothesis of a occasional fragmentation of the European sovereign bond markets (De Santis and Stein, 2016, Ehrmann and Fratzscher, 2017).     

A NEW APPROACH TO ASSET INTEGRATION: METHODOLOGY AND MYSTERY

Abstract. This paper develops a new methodology to test financial market integration. Our technique is based on an intertemporal asset‐pricing model, and relies on estimating and comparing expected discount rates across asset markets. Expected discount rates are allowed to vary freely over time, constrained only by the fact that they are equal across assets. Assets are allowed to have very general risk characteristics, and are constrained only by a linear factor model of covariances with the discount rate over short time periods. We provide a variety of domestic and international empirical illustrations of our technique, and find surprisingly little evidence of integration.     

Is the public sector too large in an economy with club goods? A case when consumers differ in both tastes and incomes

In an archetypal economy with a single private good and a single shared good, the latter represents the public sector. With the shared good a club good, we ask if second-best (SB) provision of it is too small, as usually claimed for pure public goods. When consumers differ only in exogenous incomes, if the club good is a superior good in a single-club economy, overprovision in the SB occurs if club good demand is convex in income. We show this can extend to an economy where consumers differ in both tastes and incomes, depending on the covariances between consumers' incomes and their relative strength of preference for the club and private goods, and the covariances between incomes and taste parameters.     

Divisia moments of Australian consumption

Quarterly Australian consumption data, 1959–1978, are used to compute Divisia price and quantity indexes, together with Divisia variances and covariances. The quantity variances tend to exceed the price variances, and the price-quantity covariances are mostly negative. Estimates of the income flexibility are also presented.     

Divisia moments of U.S. consumption, 1929–1982

Using U.S. consumption data for 1929 to 1982, Divisia price and volume indexes are computed as well as Divisia variances and covariances. The quantity variances tend to be larger than the price variances, and the majority of the price-quantity covariances is negative.     

A cross-country consumption comparison based on divisia variances and covariances

A preliminary analysis of price and quantity data of the consumption in 16 countries, based on Divisia variances and covariances, indicates that poor countries are pairwise much more different than affluent countries are.     

Sticky information and inflation persistence: evidence from the U.S. data

This paper analyzes the relationship between sticky information and inflation persistence by implementing a novel approach to estimate the Sticky Information Phillips Curve (SIPC). The degree of sticky information is estimated using a GMM estimator that matches the covariance between inflation and the shocks that affect firms’ pricing decisions. Although the SIPC contains an infinite number of terms, the theoretical covariances derived from the model have finite dimensions, thus allowing the estimation of the structural parameters without any truncation of the original model. This work shows that sticky information is significantly different if the model is estimated by matching inflation persistence or inflation variance. Previous empirical literature found that the SIPC model does not provide an accurate representation of the US postwar inflation. This paper qualifies such a finding by demonstrating that the SIPC is able to match the inflation persistence only at the cost of mismatching the inflation variance.     

Some properties of the simple disequilibrium model with covariance

This paper investigates two difficulties that arise in disequilibrium models with non-zero covariances between demand and supply errors. The nature of these difficulties is demonstrated analytically and some preliminary observations are made about their practical, computational significance.     

Herding,anti-herding behaviour in metal commodities futures: a novel portfolio-based approach

The purpose of this article is twofold. Motivated by the heated debate on the financialization of commodities, we examine the existence of herding behaviour in metal commodities futures. In order to identify any time-dependent properties reflected in time-varying parameters, we employ the overlapping rolling window regression technique. The empirical evidence confirms a time-varying anti-herding behaviour before the global financial crisis and the absence of herding or anti-herding behaviour during the crisis. Next we attempt to formally establish the link between the documented anti-herding behaviour and portfolio management with the use of dynamic conditional correlations via the DCC-GARCH family multivariate modelling. After specifying the correlations, an in-sample recursive dynamic Markowitz portfolio is constructed and monitored. By doing so, we attribute the anti-herding behaviour to different portfolio positioning and rebalancing. On the other hand, in the absence of herding or anti-herding behaviour, we document a shift in the correlations and covariances of the commodity futures especially during the crisis, resulting in a decrease of the portfolio weights together with a substantial cash flow towards the risk-free asset.     

The time–covariance function: Properties and application

This note establishes the relationship between the time interval over which changes in two random variables are measured and the covariances between these changes for various intervals. It then shows that the properties of this relationship can be used to detect the presence of intertemporal cross serial correlations between time series data.     

Production and savings under uncertainty

This paper studies an integrated model of production and savings under uncertainty in which production inputs and the amount of savings are jointly chosen. The analysis shows that if the agent's risk preferences exhibit constant absolute risk aversion, then all results from nonintegrated or separate models of savings and production extend to the integrated framework. Under decreasing absolute risk aversion, the comparative static properties of optimal production decisions with respect to mean preserving spread and spread preserving mean parameters extend from the non-integrated to the integrated framework. However, extension of the savings model results for the same parameters requires a restriction on production technology.     

An analysis of some aspects of regulatory risk and the required rate of return for public utilities

This paper uses a modification of the continuous time asset pricing model of Cox, Ingersoll, and Ross to analyze the effect of regulatory risk on the cost of capital. Analysis shows that random errors in setting the allowed rate of return can either increase or decrease the cost of capital depending on other regulatory parameters. However, the analysis suggests that regulatory risk is not material.     

An empirical approach to ecosystem-based fishery management

Marine scientists and policymakers are encouraging ecosystem-based fishery management (EBFM), but there is limited guidance on how to operationalize the concept. We adapt financial portfolio theory as a method for EBFM that accounts for species interdependencies, uncertainty, and sustainability constraints. Illustrating our method with routinely collected data available from the Chesapeake Bay, we demonstrate the gains from taking into account variances and covariances of gross fishing revenues in setting species total allowable catches. We find over the period from 1962-2003 that managers could have increased the revenues from fishing and reduced the variance by employing EBFM frontiers in setting catch levels.     

Unit versus Ad Valorem Taxes in Multiproduct Cournot Oligopoly

The welfare dominance of ad valorem taxes over unit taxes in a single‐market Cournot oligopoly is well known. This article extends the analysis to multimarket oligopoly. Provided all ad valorem taxes are equal and positive, unit costs are constant, firms are active in all considered markets, and a representative consumer has convex preferences, ad valorem taxes are shown to dominate in multiproduct equilibrium. Conditions exist, however, under which economic efficiency declines upon replacing specific taxes with ad valorem taxes that preserve output levels. We discuss the roles of unit cost covariances across multiproduct firms, and also of complementarity in demand, in determining the extent of cost efficiencies arising under ad valorem taxation. For goods that are complementary or independent in demand, conditions are found such that industry profits decline upon use of ad valorem taxes.     

Changes in the second-moment properties of disaggregated capital flows

Using formal statistical tests, we detect (i) significant volatility increases for various types of capital flows for a period of changes in business cycle comovement among the G7 countries, and (ii) mixed evidence of changes in covariances and correlations with a set of macroeconomic variables.     

Consistent estimation of the value of statistical life

Conventional estimators of the value of statistical life are biased. People differ in risk from each of many health threats, ability to reduce these risks, willingness to pay to reduce risk, and other utility parameters—creating a problem of multi-dimensional heterogeneity existing single-equation methods cannot handle. Herein we propose a general method of moments (GMM) approach that uses functional relationships between underlying parameters and observed data to estimate a person's willingness to pay for mortality risk reduction. This approach yields a consistent estimate of the value of statistical life. We use simulations to show that the GMM estimate of the value of statistical life performs well even when combining data from different sources that are sampled at different, low frequencies.     

基于不同专利战略的科技银行信贷动态决策与风险管理研究

高新技术企业既可先获取专利保护,再进行商业化;也可在研发成功、技术保密状态下直接进行商业化。从科技银行角度出发,建立了基于不同专利战略的科技银行信贷动态决策模型。模型全面、客观地对高新技术项目价值进行了评估,并对科技银行的信贷决策进行了指导。给出了模型参数的确定方法,并分析了各参数对信贷决策的影响,结合案例验证了此模型在科技银行信贷决策问题上的分析结果,提出了改进科技银行信贷决策评价方法以及进行信贷风险有效管理的政策建议。     

项目主体抗风险努力水平改善研究

本文基于风险能量理论分析了项目风险的发生和传递机理,相对于项目风险发生的客观性而言,项目主体的抗风险能力和抗风险努力是决定风险形成的重要参数,也是现代项目风险管理中所忽略的内容.其中抗风险努力水平是项目风险的主观参数,有效的对其利用可以缓解项目风险的恶性传递现象,作为主观性参数,对于该参数的提升有赖于有效的监控机制.因此,本文基于委托-代理理论分别针对单阶段和两阶段对项目主体的抗风险努力水平的管理和提升效果进行了分析和对比.结果表明,引入多阶段的监控机制可以有效的弥补项目一次性带来的不合作行为.因此将多阶段的激励机制引入项目风险管理体系可以作为改善项目主体抗风险行为的途径之一,为项目风险管理提供借鉴.