We introduce an axiomatic definition of a conditional convex risk mapping. By employing the techniques of conjugate duality we derive properties of conditional risk mappings. In particular, we prove a representation theorem for conditional risk mappings in terms of conditional expectations. We...

It's commonly known that the correlation between stocks increases during market turbulent periods. In this work we propose a modellization of this feature, viewed as a collective effect, rearranging a toy-model first proposed in 2001. Equities are modelled as quasi random walk variables, where...

We consider optimization problems involving convex risk functions. By employing techniques of convex analysis and optimization theory in vector spaces of measurable functions we develop new representation theorems for risk models, and optimality and duality theory for problems involving risk...

We analyze a problem of maximization of expected terminal wealth and consumption under constraints in a general framework including financial models with constrained portfolios, labor income and large investor models. By using general optional decomposition under constraints in a multiplicative...

We analyze a problem of maximization of expected terminal wealth and consumption in markets with some ``imperfection'', such as constraints on the permitted portfolios, labor income, or/and nonlinearity of portfolio dynamics. By using general optional decomposition under constraints in...

We analyze general stochastic optimization financial problems under constraints in a general framework, which includes financial models with some ``imperfection'', such as constrained portfolios, labor income, random endowment and large investor models. By using general optional decomposition...

Economic phenomena are interrelated. From a growth perspective, time analysis concerning the choices of present and future consumption and the choices between the allocation of scientific resources should be combined with a space analysis regarding the dissemination of economic activity through...

Resources used in scientific activities are, as any other, scarce. Hence, the economic system has, in every time moment, to choose how to allocate technological inputs. A technology choices model is developed, where scarce scientific resources are alternatively allocated to basic science...

Research activities have uncertain outcomes. The question asked in this paper is whether or not this uncertainty can be a central piece on the explanation of long run consumption growth paths. More specifically, we inquire how the existence of different research projects, with different degrees...

We may distinguish between two concepts of technology: a theoretical level of technology (that is, a technology possibilities frontier) and a level of technology in practice (that is, ready to use in production technology). Having these two concepts in mind, the paper develops an intertemporal...