With preference rigidities we find Pareto optima of an exchange economy, some of which involve unconsumed endowments. We show that such Pareto Optima can only be attained as market equilibria if there is a top dog in the initial endowment distribution who is richer than the other individuals....

Empirically, the covariance between stock returns varies with their volatility. We seek a robust theoretical explanation of this. With minimal assumptions, we model stochastic properties of equilibrium returns which result from the interaction between inter-temporal traders and noisy,...