A NOTE ON COMONOTONICITY AND POSITIVITY OF THE CONTROL COMPONENTS OF DECOUPLED QUADRATIC FBSDE

In this small note we are concerned with the solution of Forward-Backward Stochastic Differential Equations (FBSDE) with drivers that grow quadratically in the control component (quadratic growth FBSDE or qgFBSDE). The main theorem is a comparison result that allows comparing componentwise the signs of the control processes of two different qgFBSDE. As a byproduct one obtains conditions that allow establishing the positivity of the control process.Comment: accepted for publicatio

Identification of proteaginous pea cultivars (Pisum sativum L.) using microsatellites molecular markers

Abstract: Conventionally morphological descriptors are routinely used for establishing the identity of varieties. This kind of descriptors has some disadvantages, namely most of them are quantitative, controlled by several pairs of genes, and their expression is influenced by environmental factors. Molecular markers have a potential to facilitate this procedure, increase the reliability of decisions, and substantially save the time and space needed for experiments. In this study we intended to identify 20 cultivars of proteaginous pea (Pisum sativum L.), registered in the Community Catalog of Varieties, by microsatellites molecular markers. After DNA extraction, seven different loci were analyzed. PCR amplifications were conducted and the resulting fragments were separated on an 3,5% MS-8 agarose gel in TBE buffer, at 90V/h. The gels were analyzed for the presence/ absence of bands and a table with binary code was made. The data were processed with the statistical software NTSYS-pc, using the SIMQUAL module and Jaccard similarity coefficient, followed by UPGMA cluster analysis. With the analysis of six polymorphic loci was possible to distinguish almost all of cultivars. The most informative loci were AD61 and AB53. The cluster analysis of SSR markers separated the pea genotypes into two distinct clusters. The first cluster included the five cultivars: Isard, Cartouche, Audit, Corrent and James. The second cluster included the remaining fifteen cultivars and was further divided in two subclusters. The first subcluster had the Portuguese genotype Grisel and second subcluster contained the remaining fourteen cultivars. In this subcluster Ideal and Alezan had 100 percent similarity. There was a low number of heterozygous loci which is consistent with the nature of self pollinated species. The results showed a high potential and resolving power of SSR markers in distinctness assessment. SSR markers might also be useful in Pisum sativum L. germplasm management and genetic diversity studies.The present study was financially by the EU within the POCTEP – “Programa Operacional de Cooperação Transfronteiriça Espanha - Portugal”, Project 0186_AGROCELE_3_E

What measure of inflation should a central bank target?

This paper assumes that a central bank commits itself to maintaining an inflation target and then asks what measure of the inflation rate the central bank should use if it wants to maximize economic stability. The paper first formalizes this problem and examines its microeconomic foundations. It then shows how the weight of a sector in the stability price index depends on the sector's characteristics, including size, cyclical sensitivity, sluggishness of price adjustment, and magnitude of sectoral shocks. When a numerical illustration of the problem is calibrated to U.S. data, one tentative conclusion is that the central bank should use a price index that gives substantial weight to the level of nominal wages. JEL Classification: E42, E52, E58inflation targeting, monetary policy

Pervasive Stickiness

This paper explores a macroeconomic model of the business cycle in which stickiness of information is pervasive. We start from a familiar benchmark classical model and add to it the assumption that there is sticky information on the part of consumers, workers, and firms. We evaluate the model against three key facts that describe shortrun fluctuations: the acceleration phenomenon, the smoothness of real wages, and the gradual response of real variables to shocks. We find that pervasive stickiness is required to fit the facts. We conclude that models based on stickiness of information offer the promise of fitting the facts on business cycles while adding only one new plausible ingredient to the classical benchmark.

Sticky Information in General Equilibrium

This paper develops and analyzes a general-equilibrium model with sticky information. The only rigidity in goods, labor, and financial markets is that agents are inattentive, sporadically updating their information sets, when setting prices, wages, and consumption. After presenting the ingredients of such a model, the paper develops an algorithm to solve this class of models and uses it to study the model’s dynamic properties. It then estimates the parameters of the model using U.S. data on five key macroeconomic time series. It finds that information stickiness is present in all markets, and is especially pronounced for consumers and workers. Variance decompositions show that monetary policy and aggregate demand shocks account for most of the variance of inflation, output, and hours.

Sticky Information: A Model of Monetary Nonneutrality and Structural Slumps

This paper explores a model of wage adjustment based on the assumption that information disseminates slowly throughout the population of wage setters. This informational frictional yields interesting and plausible dynamics for employment and inflation in response to exogenous movements in monetary policy and productivity. In this model, disinflations and productivity slowdowns have a parallel effect: They both cause the path of employment to fall below the level that would prevail under full information. The model implies that, in the face of productivity change, a policy of targeting either nominal income or the nominal wage leads to more stable employment than does a policy of targeting the price of goods and services. Finally, we examine U. S. time series and find that, as the model predicts, unemployment fluctuations are associated with both inflation and productivity surprises.

Sticky information versus sticky prices: a proposal to replace the New-Keynesian Phillips curve

This paper examines a model of dynamic price adjustment based on the assumption that information disseminates slowly throughout the population. Compared to the commonly used sticky-price model, this sticky-information model displays three related properties that are more consistent with accepted views about the effects of monetary policy. First, disinflations are always contractionary (although announced disinflations are less contractionary than surprise ones). Second, monetary policy shocks have their maximum impact on inflation with a substantial delay. Third, the change in inflation is positively correlated with the level of economic activity.Prices ; Information theory

What Measure of Inflation Should a Central Bank Target?

This paper assumes that a central bank commits itself to maintaining an inflation target and then asks what measure of the inflation rate the central bank should use if it wants to maximize economic stability. The paper first formalizes this problem and examines its microeconimic foundations. It then shows how the weight of a sector in the stability price index depends on the sector's characteristics, including size, cyclical sensitivity, sluggishness of price adjustment, and magnitude of sectoral shocks. When a numerical illustration of the problem is calibrated to U. S. data, one tentative conclusion is that a central bank that wants to achieve maximum stability of economic activity should use a price index that gives substantial weight to the level of nominal wages.