In a production economy, in which agents have heterogeneous beliefs and a social planner has incomplete knowledge about which beliefs are correct, we introduce the concept of Incomplete Knowledge (IK) efficiency. IK-inefficient allocations can be improved upon without taking a stand on which...

We define the concept of market beliefs in an economy with disagreement, such that equilibrium in a representative agent economy with market beliefs is equivalent to equilibrium in the disagreement economy. In general, the mapping from individual agent beliefs to market beliefs is complex and...

We model visibility bias in the social transmission of consumption behavior. When consumption is more salient than non-consumption, people perceive that others are consuming heavily, and infer that future prospects are favorable. This increases aggregate consumption in a positive feedback loop....

The non-tradability of human capital is often cited for the failure of traditional asset pricing theory to explain agents' portfolio holdings. In this paper we argue that the opposite might be true --- traditional models might not be able to explain agent portfolio holdings because they do not...

We offer a new social approach to investment decision making and asset prices. Investors discuss their strategies and convert others to their strategies with a probability that increases in investment returns. The conversion rate is shown to be convex in realized returns. Unconditionally, active...