We give a direct proof of the Harnack inequality for a class of Kolmogorov operators associated with a linear SDE and we find the explicit expression of the optimal Harnack constant. We discuss some possible implication of the Harnack inequality in finance: specifically we infer no-arbitrage...

A certain spectrum, indexed by a\in[0,\infty], of upper bounds P_a(X;x) on the tail probability P(X\geq x), with P_0(X;x)=P(X\geq x) and P_\infty(X;x) being the best possible exponential upper bound on P(X\geq x), is shown to be stable and monotonic in a, x, and X, where x is a real number and X...

This paper examines the use of Fuzzy Cognitive Maps (FCMs) as a technique for modeling political and crisis situations and supporting the decision-making process. FCMs use notions borrowed from artificial intelligence and neural networks to combine concepts and causal relationships, in the form...

There has been considerable debate in recent years about whether well-defined business cycles even exist. At one extreme are those who assert that so-called business cycles are caused by exogenous shocks. At the other extreme are those who believe that business cycles may be endogenous, i.e.,...

In this paper we introduce a new source of data to economic history: palynological data, i.e. information about pollen grains which are preserved in bottom sediments of various water basins. We discuss how this data is collected and how it should be interpreted; develop new methods for aggregating...

It is well known among practitioners that the seasonal adjustment applied to economic time series could involve several decisions to be made by the econometrician. In this paper, I assess which aggregation strategy delivers the best results for the case of the Chilean GDP 1986-2009 quarterly...

This paper is a supplement to Ghossoub [11]. In this supplement, some of the results of Ghossoub [11], as well as the techniques used to obtain these result are extended to a more general problem of demand for contingent claims with belief heterogeneity. Moreover, a general problem of monotone...

This paper presents the dynamic behavior of a hybrid system comprising Fuzzy Cognitive Maps and Genetic Algorithms, and focuses on the behavior observed when the system reaches equilibrium at fixed points or limit cycle. More specifically, the present works examines the theoretical background of...

There is no way around it: each theory rests on a tiny set of foundational propositions. Standard economics rests on behavioral axioms. After a long intellectual detour it should be clear by now that behavioral axioms are the wrong formal departure point. Being beyond repair, they have to be...