Stochastic Models of Implied Volatility Surfaces

We propose a market–based approach to the modelling of implied volatility, in which the implied volatility surface is directly used as the state variable to describe the joint evolution of market prices of options and their underlying asset. We model the evolution of an implied volatility surface by representing it as a randomly fluctuating surface driven by a finite number of orthogonal random factors. Our approach is based on a Karhunen–Loeve decomposition of the daily variations of implied volatilities obtained from market data on SP500 and DAX options.
We illustrate how this approach extends and improves the accuracy of the well–known 'sticky moneyness' rule used by option traders for updating implied volatilities. Our approach gives a justification for the use of 'Vegas' for measuring volatility risk and provides a decomposition of volatility risk as a sum of independent contributions from empirically identifiable factors.
(J.E.L.: G130, C14, C31).     

Differences in exchange rate pass-through in the euro area

This paper focuses on the pass-through of exchange rate changes into the prices of imports made by euro area countries originating outside the area. Using data on import unit values for 13 different product categories for each country, we estimate industry-specific rates of pass-through across and within countries for all euro members. In the short-run, pass-through rates differ across industries and countries and are less than one. In the long-run neither full pass-through nor equality of pass-through rates across industries and countries can be rejected. Differences exist across euro area countries in the degree that a common exchange rate movement gets transmitted into consumer prices and costs of production indices. Most of these differences in transmission rates are due to the distinct degree of openness of each country to non-euro area imports rather than to the heterogeneity in the structure of imports.     

Discrepancies between ex ante and ex post efficiency under identical subjective probabilities

Summary. Starr (1973) showed that, if people have different subjective probabilities, ex ante and ex post efficiency conflict. Conversely, under the simple preferences that he considered, the discrepancy between ex ante and ex post efficiency disappears when subjective probabilities are identical. Here I consider identical subjective probabilities, but more general preferences. First, risk attraction is admitted. Second, I dispense with the double requirement (dubbed IZU) of additive separability and state-independence of the utility of zero-date consumption, an unrealistic requirement when modeling the investment in durable goods. I find that, under IZU, and as long as ex post preferences satisfy the natural assumption of quasiconcavity (and satisfy some technical qualifications), an ex ante efficient allocation is indeed ex post efficient, but the converse is not necessarily true under risk attraction. If, on the other hand, IZU is violated, then one can have ex ante efficient allocations that are not ex post efficient, and vice-versa, even under risk aversion. Received: June 25, 1999; revised version: March 2001     

Testing the significance and the non-linearity of the Phillips trade-off in the Euro Area

This paper tests the significance and the non-linearity of the Phillips trade-off in the aggregate Euro Area, in an unobserved components model of stochastic NAIRU and trend output featuring the Phillips equation and the Okun law as main identifying equations, with quarterly data for 1970:I-2002:III. The Phillips curve turns out to be linear and its trade-off statistically significant, while non-linearity shows up in the Okun relation. The results prove to be robust to alternative lag length structures of the model, and to alternative non-linear functional forms. The trend-cycle decompositions estimated with the model capture the main features of the Euro Area’s recent macroeconomic record.First version received: 1 September 2003 / Final version received: June 2004CEMPRE - Centro de Estudos Macroeconómicos e Previsão - is supported by the Fundação para a Ciência e a Tecnologia, Portugal, through the Programa Operacional Ciência, Tecnologia e Inovação (POCTI) of the Quadro Comunitário de Apoio III, which is financed by FEDER and Portuguese funds.We thank comments on earlier versions by Fabio Canova, Miguel St Aubyn, Alvaro Almeida, Pete Richardson, Kevin Ross, and two anonymous referees. We acknowledge James D. Hamilton’s help with the confidence bands. The usual disclaimer applies.     

Choosing sides in the trilemma: international financial cycles and structural change in developing economies

ABSTRACT

This paper analyzes the impact of international financial cycles on structural change in developing economies. It is argued that the impact of these cycles depends on the specific combination of macroeconomic and industrial policies adopted by the developing economy. The cases of Brazil and Argentina are contrasted with those of Korea and China. In the Asian economies, macroeconomic policy has been a complementary tool along with industrial policy to foster the diversification of production and capabilities. Inversely, in the case of the Latin American countries, long periods of real exchange rate (RER) appreciation, combined with the weaknesses (or absence) of industrial policies, contributed to the loss of capabilities and lagging behind.     

Measuring financial risks with copulas

This paper is concerned with the statistical modeling of the dependence structure of multivariate financial data using the concept of copulas. We select some special copulas and identify the type of dependency captured by each one. We fit copulas to daily returns and simulate from the fitted models. We compare the effect of the choice of copula on risk measures and assess the variability of one-step-ahead predictions of portfolio losses. We analyze extreme scenarios and fit extreme value copulas to the block maxima and minima from daily returns. The stress scenarios constructed are compared to those obtained using models from the extreme value theory. We illustrate the usefulness of the copula approach using two stock market indexes.     

Can teaching social dilemmas make people more prosocial? An experiment

Economics and business students regularly behave less prosocially than others. Can ethics training reverse this tendency? Results from a repeated public goods experiment reveal that it can. Students who attend an interactive lecture on social dilemmas show significantly more cooperation than others. However, the lecture does not appear to increase the incidence of reciprocal behavior. As many current social problems qualify as social dilemmas, this result stresses the importance of ethics training for policy makers and curriculum designers alike in overcoming the incentive structure of social dilemmas.     

Creating sustainable value in the hospitality industry: a (critical) multi-stakeholder study in the Dominican Republic

This paper identifies sustainable initiatives reported by “sustainability-champion” hotels in the Dominican Republic, while contrasting them against the views of key stakeholders. We adapt and apply Hart and Milstein's Sustainable Value Framework, and complement it with a Critical Management Studies approach. Our analysis relies on a mixed-methods approach (non-hierarchical k-means cluster analysis, as well as thematic and content analysis). Findings indicate that most hotels are engaging more actively in present-oriented strategies such as pollution prevention (especially, the international hotels) and in product/service stewardship. However, in the future-oriented strategies, hotels owned by local investors show higher commitment to both clean technology and innovation, and to the sustainability vision (as the firm's growth path). In addition, although the views of multiple stakeholders show a clear acknowledgment of the hospitality industry's sustainability efforts (particularly regarding education and environmental protection), they also offer differing views about the ultimate impact and value of those efforts for them and for the broader society. Our study offers a new theoretical lens to explore multi-stakeholder approaches and offers practical implications for the Dominican Republic's National Strategy for Development 2010–2030, as well as implications that may be of use for other tourism-dependent countries.     

Global financial crisis and dependence risk analysis of sector portfolios: a vine copula approach

We use regular vine (r-vine), canonical vine (c-vine) and drawable vine (d-vine) copulas to examine the dependence risk characteristics of three 20-stock portfolios from the retail, manufacturing and gold-mining equity sectors of the Australian market in periods before, during and after the 2008–2009 global financial crisis (GFC). Our results indicate that the retail portfolio is less risky than the manufacturing counterpart in the crisis period, while the gold-mining portfolio is less risky than both the retail and manufacturing sector portfolios. Both the retail and gold stocks display a higher propensity to yield positively skewed returns in the crisis periods, contrary to the manufacturing stocks. The r-vine is found to best capture the multivariate dependence structure of the stocks in the retail and gold-mining portfolios, while the d-vine does it for the manufacturing stock portfolio. These findings could be used to develop dependence risk- and investment risk-adjusted strategies for investment, rebalancing and hedging which more adequately account for the downside risk in various market conditions.     

Differences Between Short‐ and Long‐Term Risk Aversion: An Optimal Asset Allocation Perspective

This paper studies the long‐term asset allocation problem of an investor with different risk aversion attitudes to the short and the long term. We characterize investor's preferences with a utility function exhibiting a regime shift in risk aversion at some point of the multiperiod investment horizon that is estimated using threshold nonlinearity methods. Our empirical results for a portfolio of cash, bonds and stocks suggest that long‐term risk aversion is higher than short‐term risk aversion and increases with the investment horizon. The exposure of the investment portfolio from stocks to bonds and cash increases with the degree of risk aversion.