We introduce a novel description of the dynamics of the order book of financial markets as that of an effective colloidal Brownian particle embedded in fluid particles. The analysis of a comprehensive market data enables us to identify all motions of the fluid particles. Correlations between the...

This short review presents a selected history of the mutual fertilization between physics and economics, from Isaac Newton and Adam Smith to the present. The fundamentally different perspectives embraced in theories developed in financial economics compared with physics are dissected with the...

In the simplest formulation, this paper addresses the following question: Given two positive asset prices on a right-open interval, how can one decide, in an economically natural manner, whether or not this is an arbitrage-free model?In general multi-asset models of financial markets, the...

For a large financial market (which is a sequence of usual, “small” financial markets), we introduce and study a concept of no asymptotic arbitrage (of the first kind) which is invariant under discounting. We give two dual characterisations of this property in terms of (1) martingale-like...

We study general undiscounted asset price processes, which are only assumed to be non- negative, adapted and RCLL (but not a priori semimartingales). Traders are allowed to use simple (piecewise constant) strategies. We prove that under a discounting-invariant condition of absence of arbitrage,...

In general multi-asset models of financial markets, the classic no-arbitrage concepts NFLVR and NUPBR have the serious shortcoming that they depend crucially on the way prices are discounted. To avoid this economically unnatural behaviour, we introduce a new way of defining “absence of...

The paper rst shows that nancial market equilibria need not to exist if agents possesscumulative prospect theory preferences with piecewise-power value functions. This is due tothe boundary behavior of the cumulative prospect theory value function, which might causean innite short-selling...

We examine the optimal allocation of assets in the portfolio of a Colombian homeowner conditional on various levels of the house value to net wealth ratio. The high rate of home ownership and low rates of investment in financial assets indicate that households allocate most of their wealth to...

In this study, we examine the rationale that informed traders use in choosing various financial instruments in order to speculate on the volatility of the underlying asset, here a common stock. Using a continuous-time trading model, we demonstrate that the quality of the private information...

A random variable dominates another random variable with respect to the covariance order if the covariance of any two monotone increasing functions of this variable is smaller. We characterize completely the covariance order, give strong sufficient conditions for it, present a number of examples...