Turning values concrete: the role and ways of business selection in local currency schemes

Alternative consumption schemes require the selection of producers and traders according to criteria and through processes that should make alternative values concrete. The way values turn concrete is crucial for the effectiveness of such projects. This paper investigates the ways criteria and processes are defined and their real meanings and uses through the case of associative local currencies. Drawing on the framework of proximities, it analyses local currency schemes as combining proximities (geographical and non-geographical) and selection processes set up for providers wishing to join. Selection processes may be based on a charter, an approval committee and screening criteria. The objectives of the selection, its measures in principle, the way in which it is applied as well as the practical consequences are discussed. Even when charters and formal participatory schemes for selecting providers are established, proximities appear as the keystone of selection and trust.     

Conditional ordering extensions

We produce a solution to the problem of extending a quasiordering conditional on a finite list of ex-ante comparisons between pairs. This constitutes yet another extension of the classical Szpilrajn’s theorem. Some examples of use of our result follow.     

Short-term asymptotics for the implied volatility skew under a stochastic volatility model with Lévy jumps

The implied volatility skew has received relatively little attention in the literature on short-term asymptotics for financial models with jumps, despite its importance in model selection and calibration. We rectify this by providing high order asymptotic expansions for the at-the-money implied volatility skew, under a rich class of stochastic volatility models with independent stable-like jumps of infinite variation. The case of a pure-jump stable-like Lévy model is also considered under the minimal possible conditions for the resulting expansion to be well defined. Unlike recent results for “near-the-money” option prices and implied volatility, the results herein aid in understanding how the implied volatility smile near expiry is affected by important features of the continuous component, such as the leverage and vol-of-vol parameters. As intermediary results, we obtain high order expansions for at-the-money digital call option prices, which furthermore allow us to infer analogous results for the delta of at-the-money options. Simulation results indicate that our asymptotic expansions give good fits for options with maturities up to one month, underpinning their relevance in practical applications, and an analysis of the implied volatility skew in recent S&P 500 options data shows it to be consistent with the infinite variation jump component of our models.     

The fundamental theorem of asset pricing under transaction costs

This paper proves the fundamental theorem of asset pricing with transaction costs, when bid and ask prices follow locally bounded càdlàg (right-continuous, left-limited) processes. The robust no free lunch with vanishing risk condition (RNFLVR) for simple strategies is equivalent to the existence of a strictly consistent price system (SCPS). This result relies on a new notion of admissibility, which reflects future liquidation opportunities. The RNFLVR condition implies that admissible strategies are predictable processes of finite variation. The Appendix develops an extension of the familiar Stieltjes integral for càdlàg integrands and finite-variation integrators, which is central to modelling transaction costs with discontinuous prices.     

Inertia Risk: Improving Economic Models of Catastrophes*

We model endogenous catastrophic risk in a new way. We call it “inertia risk”, which accounts for delays between physical variables and the hazard rate – a characteristic often observed in reality. The added realism significantly affects optimal policies relative to the standard model of catastrophic risk. The probability of a catastrophe occurring at some point in time can span the entire interval [0,1], and is not 0 or 1 as is typical in standard models. Inertia risk can also generate path dependences. We illustrate the implications for policy in a simple model of climate change.     

The effects of macroeconomic stability on foreign trade. An analysis for Spain, 1986–2000

Two main factors underlie the rebirth of interest in the study of the influence of the real exchange rate on trade, the reduction of its volatility and the current trend towards price stability. The objective of this study is to analyse the effects of the process of nominal convergence, required of the European member states for the fulfilment of monetary integration, on foreign trade flows. The case of Spain, which is especially interesting in this context, is studied for the period 1986 to 2000. The results of estimating the aggregate functions of the export and import of goods shows how macroeconomic stability has altered the behaviour of trade with respect to the two basic determinants – income and prices – how it has caused a significant structural change in the real exchange rate and, finally, how it has laid the explanatory bases for transactions in the twenty-first century with the single currency – the euro.     

The family gap and family friendly policies: the case of Norway

Norway has among the most generous family policies in the world. The most recent is the cash-for-care reform, which was implemented in 1998. We answer two main questions in this article: What is the level of the family gap in such a generous regime and how has it developed as a consequence of the latest reform? Results suggest that the family gap is rather modest in Norway compared to many other countries and we find no evidence of a worsening of the gap in recent years. A positive interpretation of these results is that the Norwegian labour market is fairly flexible, in the sense that it seems to be able to absorb even more generous family policies.     

Hedging Housing Risk in London

This paper investigates the benefits of allowing households to compensate the portfolio distortion due to their housing consumption through investments in housing price derivatives. Focusing on the London market, we show that a major loss from over-investment in housing is that households are forced to hold a very risky portfolio. However, the strong performance of the London housing market means that little is lost in terms of expected returns. Even households with limited wealth are better off owning their home rather than renting and investing in financial assets, as long as they are willing to face the financial risk involved. In this context, access to housing price derivatives would benefit most poor homeowners looking to limit their risk exposure. It would also benefit wealthier investors looking for the high returns provided by housing investments without the costs of direct ownership of properties. Comparisons with French, Swedish and U.S. data provide a broader perspective on our findings.