A multivariate Lévy process model with linear correlation

In this paper, we develop a multivariate risk-neutral Lévy process model and discuss its applicability in the context of the volatility smile of multiple assets. Our formulation is based upon a linear combination of independent univariate Lévy processes and can easily be calibrated to a set of one-dimensional marginal distributions and a given linear correlation matrix. We derive conditions for our formulation and the associated calibration procedure to be well-defined and provide some examples associated with particular Lévy processes permitting a closed-form characteristic function. Numerical results of the option premiums on three currencies are presented to illustrate the effectiveness of our formulation with different linear correlation structures.     

Gram–Charlier densities: a multivariate approach

This paper introduces a new family of multivariate distributions based on Gram–Charlier and Edgeworth expansions. This family encompasses many of the univariate semi-non-parametric densities proposed in financial econometrics as marginal of its different formulations. Within this family, we focus on the analysis of the specifications that guarantee positivity to obtain well-defined multivariate semi-non-parametric densities. We compare two different multivariate distributions of the family with the multivariate Edgeworth–Sargan, Normal, Student's t and skewed Student's t in an in- and out-of-sample framework for financial returns data. Our results show that the proposed specifications provide a reasonably good performance, and would therefore be of interest for applications involving the modelling and forecasting of heavy-tailed distributions.     

The αVG model for multivariate asset pricing: calibration and extension

Luciano and Semeraro proposed a class of multivariate asset pricing models where the asset log-returns are modeled by a multivariate Brownian motion time-changed by a multivariate subordinator which consists of the weighted sum of a common and an idiosyncratic subordinator. In the original setting, Luciano and Semeraro imposed some constraints on the subordinator parameters such that the multivariate subordinator is of the same subordinator sub-class as its components, leading to asset log-returns of a particular Lévy type. This restriction leads to marginal characteristic functions which are independent on the common subordinator setting. In this paper, we propose to extend the original model by relaxing the constraints on the subordinator parameters, leading to marginal characteristic functions which become a function of the whole parameter set. Under this generalized version, the volatility of the log-returns depends on both the common and idiosyncratic subordinator settings, and not only on the idiosyncratic one, which makes the generalized model more in line with the empirical evidence of the presence of both an idiosyncratic and a common component in the business clock. For the numerical study, we compare the calibration fit of both univariate option surfaces and market implied correlations for a period extending from the 2nd of June 2008 until the 30th of October 2009 under the two model settings and assess the calibration risk arising from different calibration procedures by pricing traditional multivariate exotic options. In particular we show that the decoupling calibration procedure fails to accurately replicate the market dependence structure under the original model for highly correlated asset returns and we propose an alternative methodology which rests on a joint calibration of the univariate and the dependence structure and which leads to an accurate fit of the market reality under both the generalized and original models.     

Is Germany a model for managers?

Most American managers have a hard time making sense of Germany. The country has a fraction of the resources and less than one-third the population of the United States. Labor costs are substantially higher, paid vacations are at least three times as long, and strong unions are deeply involved at all levels of business, from the local plant to the corporate boardroom. Yet German companies manage to produce internationally competitive products in key manufacturing sectors, making Germany the greatest competitive threat to the United States after Japan. The seemingly paradoxical nature of the German economy typically evokes one of two diametrically opposed responses. The first is to celebrate the German economy as a "model" worth emulating--indeed, as the answer to declining U.S. competitiveness. The alternative, more skeptical response is to question Germany's staying power in a new, more competitive global economy. According to Kirsten Wever and Christopher Allen, the problem with both points of view is that they miss the forest for the trees. Observers are so preoccupied with praising--or blaming--individual components of the German economy that they fail to see the dynamic logic that ties these components together into a coherent system. In their review of recent research on the German business system, Wever and Allen argue that managers can learn an important lesson from Germany. In the global economy, competition isn't just between companies but between entire socioeconomic systems. Germany's ability to design a cohesive economic and social system that adapts continuously to changing requirements goes a long way toward explaining that country's competitive success.     

What good is a volatility model?

A volatility model must be able to forecast volatility; this is the central requirement in almost all financial applications. In this paper we outline some stylized facts about volatility that should be incorporated in a model: pronounced persistence and mean-reversion, asymmetry such that the sign of an innovation also affects volatility and the possibility of exogenous or pre-determined variables influencing volatility. We use data on the Dow Jones Industrial Index to illustrate these stylized facts, and the ability of GARCH-type models to capture these features. We conclude with some challenges for future research in this area.     

Mean–variance and mean–semivariance portfolio selection: a multivariate nonparametric approach

While univariate nonparametric estimation methods have been developed for estimating returns in mean-downside risk portfolio optimization, the problem of handling possible cross-correlations in a vector of asset returns has not been addressed in portfolio selection. We present a novel multivariate nonparametric portfolio optimization procedure using kernel-based estimators of the conditional mean and the conditional median. The method accounts for the covariance structure information from the full set of returns. We also provide two computational algorithms to implement the estimators. Via the analysis of 24 French stock market returns, we evaluate the in-sample and out-of-sample performance of both portfolio selection algorithms against optimal portfolios selected by classical and univariate nonparametric methods for three highly different time periods and different levels of expected return. By allowing for cross-correlations among returns, our results suggest that the proposed multivariate nonparametric method is a useful extension of standard univariate nonparametric portfolio selection approaches.     

Social imaginaries and Big History: Towards a new planetary consciousness?

A sustainable global future depends on a fundamental shift from the currently dominant national imaginary to a global imaginary. Most of human reasoning is based on prototypes, framings and metaphors that are seldom explicit; although they can be forged, usually they are merely presupposed in everyday reasoning and debates. The background social imaginary offers explanations of how ‘we’ fit together, how things go on between us, the expectations we have of each other and outsiders, and the deeper normative notions and images that underlie those expectations. We argue that although the 17th and 18th century scientific and social revolutions generated prototypes, metaphors, framings and related conceptions of time and space that pointed towards a global imaginary, there were deep-seated structural reasons for the ‘nation’ to become, at least temporarily, the central category of human existence and belonging. By the early 21st century, there are already widespread metaphors that envisage the human world as a whole—from the ‘global shopping mall’ or ‘global village’ to the ‘spaceship Earth’. Yet, compared to the rich poetics of national imaginaries, the proposed prototypes, metaphors and framings are often thin. Evoking innovative myths about shared human existence and destiny, Big History helps to articulate the rising global imaginary in terms that motivate transformative and progressive politics in the 21st century.     

Pricing vulnerable claims in a Lévy-driven model

We obtain an explicit expression for the price of a vulnerable claim written on a stock whose predefault dynamics follows a Lévy-driven SDE. The stock jumps to zero at default with a hazard rate given by a negative power of the stock price. We recover the characteristic function of the terminal log price as the solution of an infinite-dimensional system of complex-valued first-order ordinary differential equations. We provide an explicit eigenfunction expansion representation of the characteristic function in a suitably chosen Banach space and use it to price defaultable bonds and stock options. We present numerical results to demonstrate the accuracy and efficiency of the method.     

Towards a fair degrowth-society: Justice and the right to a ‘good life’ beyond growth

A critical scrutiny is presented of the ethical assumptions of growth and degrowth theories with respect to distributive justice and the normative conditions for a ‘good human life’. An argument is made in favor of Sen's and Nussbaum's ‘capabilities approach’ as the most suitable theoretical framework for addressing these questions. Since industrialization economic growth has played a key-role as an attraction pole, around which issues of social justice, political stability, and welfare protection seemed to gravitate. Accordingly, it is considered as a necessary condition for both intragenerational and intragenerational justice. These assumptions have been subjected to substantial critique by degrowth-thinkers, according to which economic growth is rather a threat than a condition for intragenerational and intergenerational justice. However, a theoretical underpinning of these assumptions is missing so far. In the paper I analyze the ethical and moral assumptions in both approaches by focusing on the theories of justice that are implicitly laid down as a background for their arguments (welfarism, resourcism, and the capabilities-approach). In a detailed analysis of the main critical points formulated by degrowth advocates I take the capabilities approach perspective and show why it can offer a more adequate normative underpinning for the conceptualization of a degrowth society.     

Latin American stock markets’ volatility spillovers during the financial crises: a multivariate FIAPARCH-DCC framework

The main purpose of this paper is to analyse the volatility spillovers in Latin American emerging stock markets. A multivariate Fractionally Integrated Asymmetric Power ARCH model with dynamic conditional correlations of Engle (1982 Engle, R. F. 1982. Autoregressive conditional heteroscedasticity with estimates of the variance of United Kingdom inflation. Econometrica, 50: 987–1007. [Crossref], [Web of Science ®] , [Google Scholar]) with a Student-t distribution is employed. We examine whether considering for long memory and asymmetry in emerging stock markets behaviour may provide more insights into the volatility spillovers phenomenon. In this paper we select daily frequency stock indexes covering four emerging countries in Latin America for the period (January 1995–September 2009). Our results point out the importance of volatility spillovers in these countries. Moreover, long memory and asymmetry in emerging stock market dynamics seem to provide more insights into the transmission of volatility shocks. More interestingly, the analysis of the DCCEs behaviour over time via multivariate cointegration, vector error correction model and the Cholesky variance decomposition shows shifts behaviour around major Latin American financial crisis and recent subprime crisis. On the practical side, these results may be useful for international portfolio managers and Latin American stock market authorities.     

Extending the Lee–Carter model: a three-way decomposition

In this paper, we focus on a Multi-dimensional Data Analysis approach to the Lee–Carter (LC) model of mortality trends. In particular, we extend the bilinear LC model and specify a new model based on a three-way structure, which incorporates a further component in the decomposition of the log-mortality rates. A multi-way component analysis is performed using the Tucker3 model. The suggested methodology allows us to obtain combined estimates for the three modes: (1) time, (2) age groups and (3) different populations. From the results obtained by the Tucker3 decomposition, we can jointly compare, in both a numerical and graphical way, the relationships among all three modes and obtain a time-series component as a leading indicator of the mortality trend for a group of populations. Further, we carry out a correlation analysis of the estimated trends in order to assess the reliability of the results of the three-way decomposition. The model's goodness of fit is assessed using an analysis of the residuals. Finally, we discuss how the synthesised mortality index can be used to build concise projected life tables for a group of populations. An application which compares 10 European countries is used to illustrate the approach and provide a deeper insight into the model and its implementation.     

Conditional risk–return relationship in a time-varying beta model

We investigate the asymmetric risk–return relationship in a time-varying beta CAPM. A state space model is established and estimated by the Adaptive Least Squares with Kalman foundations proposed by McCulloch. Using S&P 500 daily data from 1987:11–2003:12, we find a positive risk–return relationship in the up market (positive market excess returns) and a negative relationship in the down market (negative market excess returns). This supports the argument of Pettengill et al., who use a constant beta model. However, our model outperforms theirs by eliminating the unexplained returns and improving the accuracy of the estimated risk price.     

On a Sparre Andersen risk model perturbed by a spectrally negative Lévy process

In this paper, we consider a Sparre Andersen risk model perturbed by a spectrally negative Lévy process (SNLP). Assuming that the interclaim times follow a Coxian distribution, we show that the Laplace transforms and defective renewal equations for the Gerber–Shiu functions can be obtained by employing the roots of a generalized Lundberg equation. When the SNLP is a combination of a Brownian motion and a compound Poisson process with exponential jumps, explicit expressions and asymptotic formulas for the Gerber–Shiu functions are obtained for exponential claim size distribution and heavy-tailed claim size distribution, respectively.     

Foresight education in Australia—Time for a hybrid model?

This paper revisits the original design parameters of what was a ‘new’ Masters in Strategic Foresight that commenced at Swinburne University in 2001. It explores which of the original purposes and assumptions have stood the test of time over the course of a decade and analyses how the course has evolved, partly through design and partly through necessity. The paper reflects on the primary contribution of the Masters teaching experience and proposes that encouraging the students to develop philosophical ‘literacy’ operated to develop both the practicality of their use of methods and the capacity of their leadership and critical thinking. A secondary contribution reiterates the importance of ‘place’ and the necessity of ‘sufficient time’ for adult development to occur.     

The Tourinho model: neglected nugget or a receding relic?

This article evaluates Tourinho's (1979b Tourinho, O. A.F. 1979b. “The valuation of reserves of natural resources: an option pricing approach”. Berkeley: University of California. PhD thesis [Google Scholar]) work as one of the earliest contributors to the real options literature. His model pioneered the application of risk neutrality to uncertain investments, but his originality of introducing an option-holding cost albeit to overcome the extraction paradox is rarely imitated. We claim that the combination of a convenience yield and an option-holding cost produces a more satisfying representation. Moreover, variations in the holding cost give rise to a host of investment decisions ranging from the standard real option solution for a zero-holding cost to a net present value solution for an infinite-holding cost. Not only does the holding cost mediate between these two poles, but it provides the option seller (usually a landowner or a government) with a policy instrument for influencing the extraction timing and thus the extraction profit of the option buyer. We derive the holding cost that optimizes the landowner's combined value of the option premium, holding costs and eventual royalties.     

Bubbles and crashes in a Black�CScholes model with delay

This paper studies the asymptotic behaviour of an affine stochastic functional differential equation modelling the evolution of the cumulative return of a risky security. In the model, the traders of the security determine their investment strategy by comparing short- and long-run moving averages of the security??s returns. We show that the cumulative returns either obey the law of the iterated logarithm, but have dependent increments, or exhibit asymptotic behaviour that can be interpreted as a runaway bubble or crash.     

Pricing discrete path-dependent options under a double exponential jump–diffusion model

We provide methodologies to price discretely monitored exotic options when the underlying evolves according to a double exponential jump diffusion process. We show that discrete barrier or lookback options can be approximately priced by their continuous counterparts’ pricing formulae with a simple continuity correction. The correction is justified theoretically via extending the corrected diffusion method of Siegmund (1985). We also discuss the jump effects on the performance of this continuity correction method. Numerical results show that this continuity correction performs very well especially when the proportion of jump volatility to total volatility is small. Therefore, our method is sufficiently of use for most of time.