The rapidly growing federal government debt has become a concern for policy makers and the public. Yet the U.S. government has seemingly unbounded access to credit at low interest rates. Historically, Treasury yields have been below the growth rate of the economy. The paper examines the...

We study the sustainability of pension systems using a life-cycle model with distortionary taxation that sets an upper limit to the real value of tax revenues. This limit implies an endogenous threshold dependency ratio, i.e. a point in the cross-section distribution of the population beyond...

In many spatial resource models it is assumed that the agent is able to determine the harvesting activity over the complete spatial domain. However, agents frequently have only access to a resource at particular locations at which the moving biomass, such as fish or game, may be caught or...

For thousands of years, humans have known the value of honeybees in agriculture. Their pollination services are crucial for the mankind, the Global ecosystem and food production. The recently documented decline of the honeybee colonies in the world is alarming and may threaten the whole living...

Predator-prey relationships account for an important part of all interactions between species. In this paper we provide a microfoundation for such predator-prey relations in a food chain. Basic entities of our analysis are representative organisms of species modelled similar to economic...

In recent years a large number of experimental studies have documented the existence of strong reciprocity among humans. Strong reciprocity means that people willingly repay gifts and punish the violation of cooperation and fairness norms even in anonymous one-shot encounters with genetically...

The paper offers a proof that expected utility maximisation with logarithmic utility is a dominant preference in the biological selection process in the sense that a population following any other preference for decision-making under risk will, with a probability that approaches certainty,...

Based on economic methodology we model an ecosystem with two species in predator-prey relationship: mice feed on grain and grain feeds on a resource. With optimizing behaviour of individual organisms a short-run ecosystem equilibrium is defined and characterized that depends on the farmer’s...

In this paper we develop a micro ecosystem model whose basic entities are representative organisms which behave as if maximizing their net offspring under constraints. Net offspring is increasing in prey biomass intake, declining in the loss of own biomass to predators and Allee's Law applies....

It is a well known fact that economic development and distance to the equator are positively correlated variables in the world today. It is perhaps less well known that as recently as 1500 C.E. it was the other way around. The present paper provides a theory of why the "latitude gradient"...