sl(2)-Trivial Deformations of Vect_{Pol}(R)-Modules of Symbols

We consider the action of Vect_{Pol}(R) by Lie derivative on the spaces of symbols of differential operators. We study the deformations of this action that become trivial once restricted to sl(2). Necessary and sufficient conditions for integrability of infinitesimal deformations are given.Comment: This is a contribution to the Special Issue on Deformation Quantization, published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGMA

Core Inflation Measure and Its Effect on Economic Growth and Employment in Tunisia

The aim of this study is to present a measure for the core inflation in Tunisia. This measure consists in a six-variable structural vector autoregression model covering the period 1975Q1-2014Q4. Our results show that the observed inflation rate exceeds the core inflation when demand rises and conversely when there is a low growth. This seems to be reasonable as core inflation has a deterministic tendency and, therefore, the monetary impulse largely accounts for the evolution of inflation. Our findings also support the idea that there is a weak positive correlation between the inflation rate and the industrial production index in the short run. This core inflation is also observed to have a weak effect on unemployment over the short and long runs. Thus, this type of inflation should be taken into account as an important element for the determination of a targeted inflation rate and for future predictions and decisions of the monetary authorities