Efficient Calibration of Trinomial Trees for One-Factor Short Rate Models

In this paper we propose a computationally efficient implementation of general one factor short rate models with a trinomial tree. We improve the Hull–Whites procedure to calibrate the tree to bond prices by circumventing the forward rate induction and numerical root search algorithms. Our calibration procedure is based on forward measure changes and is as general as the Hull–White procedure, but it offers a more efficient and flexible method of constructing a trinomial term structure model. It can be easily implemented and calibrated to both prices and volatilities. JEL classification G13, C6     

Short horizons, time inconsistency, and optimal social security

We study the optimal provision of social security in a dynamically efficient economy using a continuous-time overlapping-generations model in which consumers have short planning horizons. The short-horizon mechanism leads to dynamic optimization that is time-inconsistent over the life cycle. Our calibrated general-equilibrium results are generally supportive of social security for a wide array of social welfare functions. Thus, the basic life-cycle model can be augmented with only this slight twist in order to rationalize a social security program with the current U.S. tax rate.     

On the robustness of short–term interest rate models

This paper investigates the robustness of a range of short–term interest rate models. We examine the robustness of these models over different data sets, time periods, sampling frequencies, and estimation techniques. We examine a range of popular one–factor models that allow the conditional mean (drift) and conditional variance (diffusion) to be functions of the current short rate. We find that parameter estimates are highly sensitive to all of these factors in the eight countries that we examine. Since parameter estimates are not robust, these models should be used with caution in practice.     

¿Influyen las Normas Internacionales de Información Financiera en el riesgo de las acciones?

The present research has two objectives. First, we study the determinants of stock risk. Second, we analyze whether International Financial Reporting Standard (IFRS) implemented in the Spanish market in 2005 has affected these determinants. It is quite important for both entrepreneurs and management professionals to understand the accounting information and macroeconomic factors that explain stock risk, since it suggests which factors can be used to estimate this risk, and hence, to analyze the evolution of cost of capital or discount rate. The discount rate plays an important role in wide range of financial decisions; whose value depends on the risk among other factors. Therefore, it is significant to obtain an objective estimation of discount rate, which is difficult to handle specifically in the context of small and medium sized enterprises (SMEs). Effective management involves the ability to forecast future changes, capture positive effects, and minimize negative ones. Once we find out the variables that can be utilized to explain the risk, we can observe and analyze their evolution to anticipate future changes in the discount rate.     

Pre‐Issuance Hedging of Fixed‐Rate Debt

This article analyzes several corporate hedging strategies to manage interest rate risk on fixed‐rate debt prior to issuance. The authors start by considering these strategies using a highly stylized model: a binomial forward interest rate tree that, while simple in design, illustrates derivative pricing methodologies that are used in practice. Under a given rate volatility assumption, they demonstrate expected outcomes when entering a forward bond contract, a forward‐starting pay‐fixed interest swap, and a purchased option on that swap, as well as the “default” alternative of doing nothing. In principle, the decision of whether or not to hedge, as well as how to do so, depends on management's view of future interest rate volatility and degree of comfort with possible outcomes. The authors then assess the pros and cons of hedging strategies, with considerable emphasis on practical considerations. For example, while their theoretical model would allow an issuer to “lock” a specific debt issuance, in practice one can hedge only “benchmark” interest rate risk. The authors describe the use of both Treasury locks and forward‐starting swaps to address unexpected benchmark yield changes, and discuss how factors such as the time to issuance affect an issuer's choice of instrument. For instance, Treasury locks are typically used when the time to issuance is relatively short, while interest rate swaps are more common for longer times to issuance. The article also discusses circumstances in which a “do nothing” strategy may be preferable to other alternatives, as well as the disadvantages of issuing in advance. Finally, the authors describe the impact of financial accounting on different hedge strategies.     

Interest Rates as Options

Since people can hold currency at a zero nominal interest rate, the nominal short rate cannot be negative. The real interest rate can be and has been negative, since low risk real investment opportunities like filling in the Mississippi delta do not guarantee positive returns. The inflation rate can be and has been negative, most recently (in the United States) during the Great Depression. The nominal short rate is the “shadow real interest rate” (as defined by the investment opportunity set) plus the inflation rate, or zero, whichever is greater. Thus the nominal short rate is an option. Longer term interest rates are always positive, since the future short rate may be positive even when the current short rate is zero. We can easily build this option element into our interest rate trees for backward induction or Monte Carlo simulation: just create a distribution that allows negative nominal rates, and then replace each negative rate with zero.     

A Note of Caution on Shadow Rate Estimates

Shadow short rate (SSR) estimates are generated regressors proposed as a proxy for policy interest rates during unconventional monetary policy (UMP) periods. However, using the Wu and Xia (2016) shadow/lower-bound model, I show that SSR estimates can be sensitive to minor choices in their estimation. Used subsequently in a small macroeconomic model, those sensitivities lead to wide variations in the inferred effects of UMP on inflation and unemployment outcomes. Therefore, it should not be presumed that any SSR series will necessarily be quantitatively useful. Vetting SSR series allows appropriate SSR series to be retained within the suite of UMP indicators.     

Trust and accountability in UK charities: Exploring the virtuous circle

Public trust and confidence in charities is essential for the achievement of their missions. However, recent evidence suggests that trust in UK charities has been damaged, potentially affecting charities' and the charity sector's sustainability and effectiveness. This paper constructs accountability as an important means of developing, maintaining and restoring trust in charities. Through a series of interviews with charity managers, it investigates the public and private mechanisms used in discharging accountability to, and building trust with, charities' main stakeholder groups. The paper identifies the use of a wide range of mechanisms, often highly tailored to particular stakeholders' perceived information needs, which are seen as critical in this process. It is argued that the use and interplay of these can create a ‘virtuous circle’ of accountability and trust, where each reinforces the other. It is argued that where this is achieved, trust in individual charities, and the sector as a whole, can be enhanced.     

世界储备货币变化趋势及其控制

世界储备货币规模过度增长和欧元逐渐替换美元、英镑赶超日元的结构变化是1999—2007期间世界储备货币变化的两大特征。世界经济一体化程度和国际经济交易规模的不断上升导致国际储备货币规模的上升,储备货币发行国的经济增长、货币政策和汇率水平决定其在世界储备货币中的结构变化。世界储备货币过度增长带来诸多负面后果,短期内控制储备货币发行国经常项目逆差和货币发行规模、非储备货币国家适度持有和合理利用储备货币,长期内构建与经济实力结构相适应的国际货币体系可以有效控制储备货币的过度增长。     

Survivor Derivatives: A Consistent Pricing Framework

Survivorship risk is a significant factor in the provision of retirement income. Survivor derivatives are in their early stages and offer potentially significant welfare benefits to society. This article applies the approach developed by Dowd et al. (2006) , Olivier and Jeffery (2004) , Smith (2005) , and Cairns (2007) to derive a consistent framework for pricing a wide range of linear survivor derivatives, such as forwards, basis swaps, forward swaps, and futures. It then shows how a recent option pricing model set out by Dawson et al. (2009) can be used to price nonlinear survivor derivatives, such as survivor swaptions, caps, floors, and combined option products. It concludes by considering applications of these products to a pension fund that wishes to hedge its survivorship risks.     

On user costs of risky monetary assets

Summary. We extend the monetary-asset user-cost risk adjustment of Barnett, Liu and Jensen (1997) and their risk-adjusted Divisia monetary aggregates to the case of multiple non-monetary assets and intertemporal non-separability. Our model can generate potentially larger and more accurate CCAPM user-cost risk adjustments than those found in Barnett, Liu and Jensen (1997). We show that the risk adjustment to a monetary assets user cost can be measured easily by its beta. We show that any risky non-monetary asset can be used as the benchmark asset, if its rate of return is adjusted in accordance with our formula. These extensions could be especially useful, when own rates of return are subject to exchange rate risk, as in Barnett (2003).We thank participants at the 11^th Global Finance Annual Conference, Yuqing Huang, and an anonymous referee for helpful comments and suggestions.     

Efficient willow tree method for European-style and American-style moving average barrier options pricing

Moving average options are widely traded in financial markets, but exiting methods for pricing this type of option are too slow. This paper proposes two efficient willow tree methods for pricing European-style and American-style moving average barrier options (MABOs). We first solve the finite-dimensional partial differential equation model for discretely monitored MABOs by willow tree methods, and then compute the value of continuously monitored MABOs by Richardson’s two-point extrapolation. Our new willow tree method employs the interpolation error minimization technique to reduce complexity. The corresponding convergence rate and error bounds are also analyzed. It shows that our proposed methods can provide the same accuracy as the binomial tree approach and Monte Carlo simulation, but require much less computing time. The numerical experiments support our claims.     

A quantitative analysis of unemployment benefit extensions

Extensions of unemployment insurance (UI) benefits have been implemented in response to the Great Recession. This paper measures the effect of these extensions on the unemployment rate using a calibrated structural model featuring job search and consumption-saving decisions, skill depreciation, and UI eligibility. The ongoing UI benefit extensions are found to have raised the unemployment rate by 1.4 percentage points, which is about 30% of the observed increase since 2007. Moreover, the contribution of the UI benefit extensions to the elevated unemployment rate increased during 2009–2011; while the number of vacancies recovered, the successive extensions kept search intensity down.     

Bayesian comparison of several continuous time models of the Australian short rate

This paper provides an empirical analysis of a range of alternative single‐factor continuous time models for the Australian short‐term interest rate. The models are nested in a general single‐factor diffusion process for the short rate, with each alternative model indexed by the level effect parameter for the volatility. The inferential approach adopted is Bayesian, with estimation of the models proceeding through a Markov chain Monte Carlo simulation scheme. Discrimination between the alternative models is based on Bayes factors. A data augmentation approach is used to improve the accuracy of the discrete time approximation of the continuous time models. An empirical investigation is conducted using weekly observations on the Australian 90 day interest rate from January 1990 to July 2000. The Bayes factors indicate that the square root diffusion model has the highest posterior probability of all models considered.     

Capital structure,credit risk,and macroeconomic conditions

This paper develops a framework for analyzing the impact of macroeconomic conditions on credit risk and dynamic capital structure choice. We begin by observing that when cash flows depend on current economic conditions, there will be a benefit for firms to adapt their default and financing policies to the position of the economy in the business cycle phase. We then demonstrate that this simple observation has a wide range of empirical implications for corporations. Notably, we show that our model can replicate observed debt levels and the countercyclicality of leverage ratios. We also demonstrate that it can reproduce the observed term structure of credit spreads and generate strictly positive credit spreads for debt contracts with very short maturities. Finally, we characterize the impact of macroeconomic conditions on the pace and size of capital structure changes, and debt capacity.     

The Accuracy of Decision Tree Induction in a Noisy Domain for Expert Systems Construction

Many studies have shown that decision tree induction methods could be used to determine rules for expert systems. Pruning techniques are often used to increase the accuracy of an induced decision tree over the instance space. While recent results of decision tree induction show that large samples may be required to induce a decision tree of small error, recent expository studies have used very small sample sizes. In such cases it is of value to obtain a posterior evaluation of the error of the induced concept. In this paper we give three methods to estimate the accuracy of a pruned decision tree. The first method assumes uniform prior distribution. For those cases where uniform prior is not appropriate, we develop a method to obtain appropriate prior using a beta distribution. Finally, we provide a general bound which requires no assumption over the instance space. These results can be used when a pruned decision tree is used to classify the original domain or another close domain.     

The Advantage of Flexible Targeting Rules

This paper investigates the consequences of debt stabilization for inflation targeting. If the fiscal authority holds constant the real value of debt at maturity under strict inflation targeting, the equilibrium dynamics are indeterminate for a wide range of parameters and steady‐state fiscal stances. “Flexible” targeting rules that include a concern for stabilization of the output gap can restore determinacy of the equilibrium. Flexible inflation targeting appears to be more robust than flexible debt targeting to alternative parameterizations. The fiscal authority can prevent indeterminacy under strict targeting rules by committing to hold constant debt net of interest rate spending.     

On the Class of Erlang Mixtures with Risk Theoretic Applications

Abstract

A wide variety of distributions are shown to be of mixed-Erlang type. Useful computational formulas result for many quantities of interest in a risk-theoretic context when the claim size distribution is an Erlang mixture. In particular, the aggregate claims distribution and related quantities such as stop-loss moments are discussed, as well as ruin-theoretic quantities including infinitetime ruin probabilities and the distribution of the deficit at ruin. A very useful application of the results is the computation of finite-time ruin probabilities, with numerical examples given. Finally, extensions of the results to more general gamma mixtures are briefly examined.     

How good can heuristic-based forecasts be? A comparative performance of econometric and heuristic models for UK and US asset returns

This paper systematically investigates the sources of differential out-of-sample predictive accuracy of heuristic frameworks based on internet search frequencies and a large set of econometric models. The volume of internet searches helps gauge the degree of investors’ time-varying interest in specific assets. We use a wide range of state-of-the-art models, both of linear and nonlinear type (regime-switching predictive regressions, threshold autoregressive, smooth transition autoregressive), extended to capture conditional heteroskedasticity through GARCH models. The predictor variables investigated are those typical of the literature featuring a range of macroeconomic and market leading indicators. Our out-of-sample forecasting exercises are conducted with reference to US, UK, French and German data, both stocks and bonds, and for 1- and 12-months-ahead horizons. We employ several forecast performance metrics and predictive accuracy tests. Internet-search-based models are found to perform better than the average of all of the alternative models. For several country-asset-horizon combinations, particularly for UK bond returns, our heuristic models compare favourably with sophisticated econometric methods. The heuristic models are also shown to perform well in forecasting realized volatility. The baseline results are supported by several extensions and robustness checks, such as using alternative search keywords, controlling for Fama–French and Cochrane–Piazzesi factors, and implementing heuristic-based trading strategies.