Volatile Policy and Private Information: The Case of Monetary Policy

In this paper we study how volatility in monetary policy affects economic performance in the presence of endogenously chosen information structures. To isolate the effects produced by the interaction of uncertainty in monetary policy and (possibly) asymmetric information, we consider a model in which in the absence of either one of these features the equilibrium would be efficient. The equilibria that we find, with volatility and asymmetry of information, are inefficient for two reasons: first, in some cases, economic agents fail to trade, even though it is always efficient to do so; second, to capture the rents associated with being informed, agents spend resources acquiring socially useless information. Thus, in addition to the more standard effects of volatile inflation, our model calls attention to two types of costs associated with monetary uncertainty: the cost of not trading, and the cost of allocating resources to wasteful activities. The model implies that if monetary policy is not volatile all agents are symmetrically informed and hence, the outcome is efficient. Alternatively, making policy transparent,' i.e guaranteeing that all agents share the same information, serves the same purpose.

Network architecture, salience and coordination

This paper reports the results of an experimental investigation of monotone games with imperfect information. Players are located at the nodes of a network and observe the actions of other players only if they are connected by the network. These games have many sequential equilibria; nonetheless, the behavior of subjects in the laboratory is predictable. The network architecture makes some strategies salient and this in turn makes the subjects’ behavior predictable and facilitates coordination on efficient outcomes. In some cases, modal behavior corresponds to equilibrium strategies

A Generalization of Plexes of Latin Squares

A $k$-plex of a latin square is a collection of cells representing each row, column, and symbol precisely $k$ times. The classic case of $k=1$ is more commonly known as a transversal. We introduce the concept of a $k$-weight, an integral weight function on the cells of a latin square whose row, column, and symbol sums are all $k$. We then show that several non-existence results about $k$-plexes can been seen as more general facts about $k$-weights and that the weight-analogues of several well-known existence conjectures for plexes actually hold for $k$-weights

Communication, Literacy and Citizenship: a conceptual orientation in a portuguese children’s television thematic channel, K SIC

This paper highlights the consequential nature of communication, literacy and citizenship and the meta-pattern that connects everything together – the ecology of the human spirit. It argues that, just like human communication, literacy is consequential in nature for humankind. Through each of our different worlds of experience and processes of communication, we manifest both of these human conditions and co-construct everyday practices that engender a plurality of effects. Literacy is a concept common to all humankind. Thus, it forms an indivisible whole with communication. This viewpoint is at odds with that which confines literacy to being understood as the acquisition of certain competences. It is arguable that, just like communication, the human condition of literacy needs to be both encouraged and developed. We suggest here that the idea of borders in literacy should be questioned. The work of Gregory Bateson on the ecology of the human spirit – an imminent characteristic of the human species that is based on the physiological structure of the living being and is in permanent interaction and reconnection with both the biosphere and our ways of seeing the world – supports the viewpoint put forward here. From the communication mediatised by a children’s television channel, from SIC K and from the results of studies carried out into children’s use of television we draw the examples that shall illustrate the theoretical approach taken here. They also underpin two premises of an ongoing project. Firstly, television is part of the solution in that it encourages and develops communication-literacy- citizenship-education-connectivity. Secondly, human rights form a shared platform from which to orient the use of Technologies and define connection strategies for the active participation of the children

Plant level irreversible investment and equilibrium business cycles

This paper evaluates the importance of microeconomic irreversibilities for aggregate dynamics using a general equilibrium approach. To this end a real business cycle model of establishment level dynamics is formulated and analyzed. Investments decisions are subject to irreversibility constraints and consequently, are of the (S,s) variety. This complicates the analysis since the state of the economy is described by an endogenous distribution of agents. The paper develops a computational strategy that makes this class of (S,s) economies fully tractable. Contrary to what the previous literature has suggested, investment irreversibilities are found to have no effects on aggregate business cycle dynamics.Business cycles ; Investments

Fast Fencing

We consider very natural "fence enclosure" problems studied by Capoyleas, Rote, and Woeginger and Arkin, Khuller, and Mitchell in the early 90s. Given a set $S$ of $n$ points in the plane, we aim at finding a set of closed curves such that (1) each point is enclosed by a curve and (2) the total length of the curves is minimized. We consider two main variants. In the first variant, we pay a unit cost per curve in addition to the total length of the curves. An equivalent formulation of this version is that we have to enclose $n$ unit disks, paying only the total length of the enclosing curves. In the other variant, we are allowed to use at most $k$ closed curves and pay no cost per curve. For the variant with at most $k$ closed curves, we present an algorithm that is polynomial in both $n$ and $k$. For the variant with unit cost per curve, or unit disks, we present a near-linear time algorithm. Capoyleas, Rote, and Woeginger solved the problem with at most $k$ curves in $n^{O(k)}$ time. Arkin, Khuller, and Mitchell used this to solve the unit cost per curve version in exponential time. At the time, they conjectured that the problem with $k$ curves is NP-hard for general $k$. Our polynomial time algorithm refutes this unless P equals NP