Altruistic punishment - the punishment of norm violators at one's own cost without material benefit - is frequently observed in experimental economics, field studies and in people's everyday life. The existence of this ostensibly irrational behavior is often linked to other-regarding preferences...

We present a simple agent-based model to study how the proximate triggering factor of a crash or a rally might relate to its fundamental mechanism, and vice versa. Our agents form opinions and invest, based on three sources of information, (i) public information, i.e. news; (ii) information from...