This paper aims to study the structure of international trade. It establishes, through a simple formalization of exchange coefficients, that many theorems can be proved on a function of the macroscopic structure (the determinant of the matrix). This determinant is the cornerstone of indicators...

We present an extension of Borsuk's antipodal theorem (existence of a zero) for antipodally approachable correspondences without convex values. This result is a generalization of Borsuk-Ulam Theorem and has a fixed-point equivalent formulation.

The ultimate goal of risk management is the generation of efficient incomes. The objective is to generate the maximum return for a unit of risk taken or to minimise the risk taken to generate the return expected i.e. it is the optimisation of a financial institution strategy. Therefore, by...

We propose a nouvel methodology for forecasting chaotic systems which uses information on local Lyapunov exponents (LLEs) to improve upon existing predictors by correcting for their inevitable bias. Using simulations of the Rössler, Lorenz and Chua attractors, we find that accuracy gains can be...

In this article, we compare the performance of Hodrickk-Prescott and Baxter-King filters with a method of filtering based on the multi-resolution properties of wavelets. We show that overall the three methods remain comparable if the theoretical cyclical component is defined in the usual...

In this paper, we present a general statistical framework within which we can draw a new interpretation of the Laakso-Taagepera effective number of parties fragmentation index. With the particular method of sampling with probability proportional to the party sizes, we show that the...

We provide a mathematical definition of fragility and antifragility as negative or positive sensitivity to a semi-measure of dispersion and volatility (a variant of negative or positive "vega") and examine the link to nonlinear effects. We integrate model error (and biases) into the fragile or...

We propose a novel methodology for forecasting chaotic systems which is based on the nearest-neighbor predictor and improves upon it by incorporating local Lyapunov exponents to correct for its inevitable bias. Using simulated data, we show that gains in prediction accuracy can be substantial....

We consider a general equilibrium model of a private ownership economy with consumption and production externalities. Utility functions and production technologies may be affected by the consumption and production activities of all other agents in the economy. We use differential techniques to...

The aim of this paper is twofold. Starting from the population dynamics literature, which usually finds the resulting distribution of a trait in a population, according to some parents' preferences, I answer the inverted question: Which preference function would yield into a given trait...