Ambiguous beliefs may lead to speculative trade and speculative bubbles. We demonstrate this by showing that the classical Harrison and Kreps (1978) example of speculative trade among agents with heterogeneous beliefs can be replicated with agents having common ambiguous beliefs. More precisely, we show that the same asset prices and pattern of trade can be obtained in equilibrium with agents’ ...

Motivated by the behavior of asset prices, trading volume and price volatility during historical episodes of asset price bubbles, we present a continuous time equilibrium model where overconfidence generates disagreements among agents regarding asset fundamentals. With short-sale constraints, an asset owner has an option to sell the asset to other overconfident agents when they have more optimi...

the presence of bubbles in the markets and its formation has been regarded by economists and they have been looking to develop methods that can be recognized by using appropriate method for the formation of bubbles. in this paper, first, the formation of bubbles is tested using the new unit root test known as phillips test (generalized sup adf test) for 50 companies in the tehran stock exchange...

The aim of this paper is to analyse the effect introduced in the dynamics of a financial market when agents anticipate the occurrence of a correlation breakdown.What emerges is that correlation breakdowns can act both as a consequence and as a triggering factor in the emergence of financial crises rational bubbles. We propose a market with two kinds of agents: speculators and rational investors...

Rational price bubble arises when the price of an asset exceeds the asset’s fundamental value, that is, the present value of future dividend payments. The important result of Santos and Woodford (1997) says that price bubbles cannot exist in equilibrium in the standard dynamic asset pricing model with rational agents facing borrowing constraints as long as assets are in strictly positive supply...

The sharp increase in agricultural commodity prices in 2008 and in 2011 has triggered an intensive debate on the causes for these price booms. Speculative bubbles have been quoted as one factor among others for the price peaks. Against this background, our paper contributes to this discussion by implementing a novel test procedure for speculative bubbles which has been suggested in the stock ma...