[eng] Beliefs' heterogeneity, risk premium and volatility . This article analyses introducing of subjective and heterogeneous beliefs in traditional equilibrium model. The authors assume heterogeneous beliefs and answer the questions : 1 - is there a consensual belief which implies same...

The aim of this paper is to analyse the impact of heterogeneous beliefs in an otherwise standard competitive complete market economy. The construction of a consensus probability belief, as well as a consensus consumer, is shown to be valid modulo an aggregation bias, which takes the form of a...

In the context of an incomplete market or of imperfect information, it is well known that the arbitrage approach does not enable us to obtain a unique fair price for all contingent claims but only a fair pricing interval, which is known to be too large to be of great interest. We present here a...

This paper studies foundational issues in securities markets models with fixed costs of trading, i.e. transaction costs that are bounded regardless of the transaction size, such as fixed brokerage fees, investment taxes, operational and processing costs, or opportunity costs. We show that the...