Flexible Threshold Models for Modelling Interest Rate Volatility

This paper focuses on interest rate models with regime switching and extends previous nonlinear threshold models by relaxing the assumption of a fixed number of regimes. Instead we suggest automatic model determination through Bayesian inference via the reversible jump Markov Chain Monte Carlo (MCMC) algorithm. Moreover, we allow the thresholds in the volatility to be driven not only by the interest rate but also by other economic factors. We illustrate our methodology by applying it to interest rates and other economic factors of the American economy.     

中国国债回购利率波动率预测

利率风险是金融中最受人们关注的热点之一,通常是用方差或标准差来衡量利率风险。为了更好地探讨利率风险,必须对利率的动态行为进行研究,一般是通过利率模型来反映其动态特征。文章把常见单因子利率模型同GARCH模型相结合,通过对波动性的预测达到对未来风险的一种直观认识。     

宏观经济因素对房地产价格的长短期影响

本文将购房者、房产商与中央银行纳入统一的模型当中,对房价的影响因素进行理论建模,然后拓展了传统的向量自回归模型长短期分解技术,研究了利率、通货膨胀率、汇率、土地价格以及经济增长率对房价的长期和短期影响。研究表明,利率上升对房价具有长期的负向效应,短期内会加剧房价的波动;通胀预期在长期内促使资金流入房地产行业,对房价会产生推动作用,短期内,通胀促使房地产企业加快投资速度,房屋供给增加预期引起房价下降的冲击;人民币升值在长短期内均与房价上涨存在正向作用;在当前的经济和房地产发展阶段,经济增速提高时,对房地产业的投资和投机具有一定的抑制作用;土地价格长期来看推动房价上涨,短期内对房价影响的传导较慢。     

Discussion of “Nonparametric Bayesian Inference in Applications”: Bayesian nonparametric methods in econometrics

The use of Bayesian nonparametrics models has increased rapidly over the last few decades driven by increasing computational power and the development of efficient Markov chain Monte Carlo algorithms. We review some applications of these models in economic applications including: volatility modelling (using both stochastic volatility models and GARCH-type models) with Dirichlet process mixture models, uses in portfolio allocation problems, long memory models with flexible forms of time-dependence, flexible extension of the dynamic Nelson-Siegel model for interest rate yields and multivariate time series models used in macroeconometrics.     

Unspanned Macroeconomic Factors in the Yield Curve

In this article, we extract common factors from a cross-section of U.S. macro-variables and Treasury zero-coupon yields. We find that two macroeconomic factors have an important predictive content for government bond yields and excess returns. These factors are not spanned by the cross-section of yields and are well proxied by economic growth and real interest rates.     

Out-of-Sample Performance of Discrete-Time Spot Interest Rate Models

We provide a comprehensive analysis of the out-of-sample performance of a wide variety of spot rate models in forecasting the probability density of future interest rates. Although the most parsimonious models perform best in forecasting the conditional mean of many financial time series, we find that the spot rate models that incorporate conditional heteroscedasticity and excess kurtosis or heavy tails have better density forecasts. Generalized autoregressive conditional heteroscedasticity significantly improves the modeling of the conditional variance and kurtosis, whereas regime switching and jumps improve the modeling of the marginal density of interest rates. Our analysis shows that the sophisticated spot rate models in the existing literature are important for applications involving density forecasts of interest rates.     

Valuation of contingent claims with stochastic interest rate and mortality driven by Lévy processes

Abstract

In this paper, we consider a model with stochastic interest rate and stochastic mortality, which is driven by a Lévy process. Under the assumption that the stochastic mortality and interest rate are dependent, we discuss the valuation of life insurance contracts. Employing the method of change of measure together with the Bayes’ rule, we present the pricing formulas in closed form for the survival and death benefit models. Finally, numerical experiments illustrate the effects of some parameters.     

信心、货币政策与中国经济波动关系的统计检验

文章基于时变视角,依据行为经济学理论,构建了一个包含企业家信心、投资者信心、利率、货币增长率、经济增长率和通货膨胀率六变量的TVP-VAR模型,研究信心、货币政策与经济波动之间的时变特征。结果表明:企业家信心和投资者信心能够影响利率和货币增长率,即信心可以通过影响货币政策进而作用于宏观经济。货币增长率和利率能够影响投资者信心和企业家信心,进而可以通过信心影响宏观经济。从时变角度看,企业家信心一单位的正向冲击在整个样本区间内均会促进经济的增长;在短期内投资者信心和货币增长率对经济增长具有促进作用,但是在长期内货币增长率的提高会阻碍经济的增长。     

COM–Poisson cure rate survival models and an application to a cutaneous melanoma data

In this paper, we develop a flexible cure rate survival model by assuming the number of competing causes of the event of interest to follow the Conway–Maxwell Poisson distribution. This model includes as special cases some of the well-known cure rate models discussed in the literature. Next, we discuss the maximum likelihood estimation of the parameters of this cure rate survival model. Finally, we illustrate the usefulness of this model by applying it to a real cutaneous melanoma data.     

An EM-type algorithm for multivariate mixture models

This paper introduces a new approach, based on dependent univariate GLMs, for fitting multivariate mixture models. This approach is a multivariate generalization of the method for univariate mixtures presented by Hinde (1982). Its accuracy and efficiency are compared with direct maximization of the log-likelihood. Using a simulation study, we also compare the efficiency of Monte Carlo and Gaussian quadrature methods for approximating the mixture distribution. The new approach with Gaussian quadrature outperforms the alternative methods considered. The work is motivated by the multivariate mixture models which have been proposed for modelling changes of employment states at an individual level. Similar formulations are of interest for modelling movement between other social and economic states and multivariate mixture models also occur in biostatistics and epidemiology.     

The relation between unemployment and interest rate:

In bierens (1987) a granger casual relation was found between unemployment and the interest rate for the netherlands. In the present paper we will investigate whether there exists a similar granger casual relation between unemployment and interest rate for a number of other countries. It appears that, with our ARMAX modeling approach, this relationship is not confined to the netherlands, but also holds for the USA, Canada, Japan, Germany, the UK and France. For these countries the interest rate is the main explanatory variable, together with industrial production (the latter with one exception), whereas for most countries the wage rate is of minor or no importance as a determinant of unemployment. A number of economic theories can explain these phenomena of which the revenue maximization theory of baumol (1959) augmented with a flexible labor effort rate seems quite realistic     

Affine LIBOR models driven by real-valued affine processes

The class of affine LIBOR models is appealing since it satisfies three central requirements of interest rate modeling. It is arbitrage-free, interest rates are nonnegative, and caplet and swaption prices can be calculated analytically. In order to guarantee nonnegative interest rates affine LIBOR models are driven by nonnegative affine processes, a restriction that makes it hard to produce volatility smiles. We modify the affine LIBOR models in such a way that real-valued affine processes can be used without destroying the nonnegativity of interest rates. Numerical examples show that in this class of models, pronounced volatility smiles are possible.     

A model with long-term survivors: negative binomial Birnbaum-Saunders

Abstract

We propose a cure rate survival model by assuming that the number of competing causes of the event of interest follows the negative binomial distribution and the time to the event of interest has the Birnbaum-Saunders distribution. Further, the new model includes as special cases some well-known cure rate models published recently. We consider a frequentist analysis for parameter estimation of the negative binomial Birnbaum-Saunders model with cure rate. Then, we derive the appropriate matrices for assessing local influence on the parameter estimates under different perturbation schemes. We illustrate the usefulness of the proposed model in the analysis of a real data set from the medical area.     

人民币汇率应对美国非对称冲击的缓冲机制及效应分析

 本文依据汇率决定理论,构建包含人民币汇率、中美两国GDP、通货膨胀率和利率的向量自回归模型,并基于结构向量误差修正模型（SVECM）方法,识别了包含巴拉萨——萨缪尔森效应的人民币汇率决定方程及人民币汇率传递效应方程,进一步应用方差分解判断了中短期内人民币汇率应对源自美国的非对称冲击的缓冲机制。结果表明,人民币汇率长期升值趋势的根本动因是中国产出及通胀水平相对美国的提高,而汇率传递效应则是不完全的。在1-2年内,人民币汇率的波动来源主要受源自美国的需求冲击(实际冲击)影响,而在3-5年内则主要受美国货币政策扰动（名义冲击）影响。因此,央行重启人民币“汇改”将增强人民币汇率应对外部冲击的缓冲作用。     

Heterogeneity,Aggregate Uncertainty,and the Short-Term Interest Rate

This article analyzes the relationship between the short-term interest rate and diversity (i.e., the number of types) in models with heterogeneous agents and incomplete markets. The number of types needed to approximate a continuum varies across examples. In all cases, however, the number of types has little effect on the average interest rate and consumption variability. In these models, the set of state variables is large because the equilibrium law of motion depends on the cross-sectional wealth distribution. The article shows how to solve these models numerically by approximating the distribution using moments or percentiles.     

Optimal Strategies for a Long-Term Static Investor

The optimal strategies for a long-term static investor are studied. Given a portfolio of a stock and a bond, we derive the optimal allocation of the capitals to maximize the expected long-term growth rate of a utility function of the wealth. When the bond has a constant interest rate, three models for the underlying stock price processes are studied: Heston model, 3/2 model, and jump diffusion model. We also study the optimal strategies for a portfolio in which the stock price process follows a Black-Scholes model and the bond process has a Vasicek interest rate that is correlated to the stock price.     

Using the dependent wild bootstrap for the nonparametric goodness-of-fit test for density functions

In this paper, we consider the well-known nonparametric consistent model-specification test for the stationary density function (see [Aït-Sahalia Y. Testing continuous-time models of the spot interest rate. Rev Financ Stud. 1996;9:385–426; Li Q. Nonparametric testing of closeness between two unknown distribution functions. Econ Rev. 1996;15:261–274; Fan Y, Ullah A. On goodness-of-fit tests for weakly dependent processes using kernel method. J Nonparametric Stat. 2000;11:337–360]) and reinvestigate it carefully using asymptotics and simulation. Our work reveals that the test is subject to power and size distortions, which are mainly caused by dependence or convergence rate changes under the null and alternative hypothesis. A dependent wild bootstrap is newly suggested as a feasible remedy to such distortions. Our result provides a complete explanation as well as a solution to the problem that experienced by Aït-Sahalia [Testing continuous-time models of the spot interest rate. Rev Financ Stud. 1996;9:385–426], that is, that the test rejects true models too often when independent and identically distributed asymptotic critical values are used.     

我国货币替代决定因素的实证分析

本文在分析中国的货币替代程度衡量指标基础上,讨论了影响我国货币替代的因素,并基于协整检验和误差修正模型分析了各因素的影响方向和程度。结果表明贸易占GDP比例指标和中美实际利率差指标对货币替代的影响都是负向的,并且是显著的。     

Destructive weighted Poisson cure rate models

In this paper, we develop a flexible cure rate survival model by assuming the number of competing causes of the event of interest to follow a compound weighted Poisson distribution. This model is more flexible in terms of dispersion than the promotion time cure model. Moreover, it gives an interesting and realistic interpretation of the biological mechanism of the occurrence of event of interest as it includes a destructive process of the initial risk factors in a competitive scenario. In other words, what is recorded is only from the undamaged portion of the original number of risk factors.     

On bootstrap testing inference in cure rate models

Survival models deal with the time until the occurrence of an event of interest. However, in some situations the event may not occur in part of the studied population. The fraction of the population that will never experience the event of interest is generally called cure rate. Models that consider this fact (cure rate models) have been extensively studied in the literature. Hypothesis testing on the parameters of these models can be performed based on likelihood ratio, gradient, score or Wald statistics. Critical values of these tests are obtained through approximations that are valid in large samples and may result in size distortion in small or moderate sample sizes. In this sense, this paper proposes bootstrap corrections to the four mentioned tests and bootstrap Bartlett correction for the likelihood ratio statistic in the Weibull promotion time model. Besides, we present an algorithm for bootstrap resampling when the data presents cure fraction and right censoring time (random and non-informative). Simulation studies are conducted to compare the finite sample performances of the corrected tests. The numerical evidence favours the corrected tests we propose. We also present an application in an actual data set.