In this chapter, we conduct a comparative study of various traders following different trading strategies. We design an agent-based artificial stock market consisting of two opposing types of traders: “rational traders” (or “fundamentalists”) and “imitators” (or “chartists”). Rational traders trade by trying to optimize their short-term income. On the other hand, imitators trade by copying the ...

Current employment strategies usually rely on some rational compromise between hiring people with skills that are needed immediately and hiring people with skills that will likely be needed in the future. A more open approach to innovation promises access to “smart people” that are outside of your organization. But most strategies fall far short of effectively tapping that external crowd. A new...

We prove a new result on N-rational series in one variable. This result gives, under an appropriate hypothesis, a necessary and suucient condition for an N-rational series to be of star-height 1. The proof uses a theorem of Handelman on integral companion matrices.

We introduce α-synchronous relations for a rational number α. We show that if a rational relation is both αand α-synchronous for two different numbers α and α, then it is recognizable. We give a synchronization algorithm for α-synchronous transducers. We also prove the closure under boolean operations and composition of α-synchronous relations.

We consider general economies in which rational agents interact locally. The local aspect of the interactions is designed to capture in a simple abstract way social interactions, that is, socio-economic environments in which markets do not mediate all of agents’ choices, and each agent’s choice might be in part determined, for instance, by family, peer group, or ethnic group effects. We study s...

This paper offers an alternative explanation for what is typically referred to as an asset pricing bubble. We develop a model that formalizes the Cochrane (2002) convenience yield theory of technology company stocks to explain why a rational agent would buy an “overpriced” security. Agents have a desire to trade but short-sale restrictions and other frictions limit their trading strategies and ...

An elliptic divisibility sequence, generated by a point in the image of a rational isogeny, is shown to possess a uniformly bounded number of prime terms. This result applies over the rational numbers, assuming Lang’s conjecture, and over the rational function field, unconditionally. In the latter case, a uniform bound is obtained on the index of a prime term. Sharpened versions of these techni...

We analyse scenarios in which individually rational agents negotiate with each other in order to agree on deals to exchange resources. We consider two variants of the framework, one where agents can use money to compensate other agents for disadvantageous deals, and another one where this is not possible. In both cases, we analyse what types of deals are necessary and sufficient to guarantee an...

In the classic AGM belief revision theory, beliefs are static and do not change their own shape. For instance, if p is accepted by a rational agent, it will remain p to the agent. But such rarely happens to us. Often, when we accept some information p, what is actually accepted is not the whole p, but only a portion of it; not necessarily because we select the portion but because p must be perc...