78,721 research outputs found
Assessing French Inflation Persistence with Impulse Saturation Break Tests and Automatic General-to-Specific Modelling
This paper has three different motivations. Firstly, we wish to contribute to the debate on whether French inflation has been persistent since the mid-eighties. Empirical evidence in this domain has been mixed. We use the standard method of testing for breaks in the mean of the inflation series to conclude whether possible unit root findings are the result of neglected breaks. Then, we build standard autoregressive representations of inflation, using an automatic general-to-specific approach. We conclude against inflation persistence in the sample period, and the point estimates of persistence we obtain are several percentage points below those achieved with other break tests and model selection methods. Moreover, our final model is congruent. Secondly, we provide the first empirical application of the new impulse saturation break test. The resulting estimates of the break dates are in line with other literature findings and have a sound economic meaning, confirming the good performance the test had revealed in theoretical and simulation studies. Finally, we also illustrate the shortcomings of the Bai-Perron test when applied to a small sample with high serial correlation. Indeed, we show the Bai- Perron break dates’ estimates would not allow us to build a congruent autoregressive representation of inflation.Inflation Persistence, Break Tests, Model Selection, General-to-Specific
On the P-representable subset of all bipartite Gaussian separable states
P-representability is a necessary and sufficient condition for separability
of bipartite Gaussian states only for the special subset of states whose
covariance matrix are locally invariant. Although this
special class of states can be reached by a convenient
transformation over an arbitrary covariance matrix, it represents a loss of
generality, avoiding inference of many general aspects of separability of
bipartite Gaussian states.Comment: Final version with new results added. Slightly more detailed than the
accepted manuscript (to appear in Phys. Rev. A
Exact Lagrangian submanifolds, Lagrangian spectral invariants and Aubry-Mather theory
We construct graph selectors for compact exact Lagrangians in the cotangent
bundle of an orientable, closed manifold. The construction combines Lagrangian
spectral invariants developed by Oh and results by Abouzaid about the Fukaya
category of a cotangent bundle. We also introduce the notion of Lipschitz-exact
Lagrangians and prove that these admit an appropriate generalization of graph
selector. We then, following Bernard-Oliveira dos Santos, use these results to
give a new characterization of the Aubry and Mane sets of a Tonelli Hamiltonian
and to generalize a result of Arnaud on Lagrangians invariant under the flow of
such Hamiltonians.Comment: v4: final version; to appear in Math. Proc. Camb. Phil. So
Flavour changing strong interaction effects on top quark physics at the LHC
We perform a model independent analysis of the flavour changing strong
interaction vertices relevant to the LHC. In particular, the contribution of
dimension six operators to single top production in various production
processes is discussed, together with possible hints for identifying signals
and setting bounds on physics beyond the standard model.Comment: Authors corrections (references added
A Framework for the Design and Implementation of Learning Objects: a Competence-based Approach
This paper presents a framework for the design and implementation of learning objects using a competence-based approach. This framework is illustrated by the development of a standalone Windows application (Trilho GOA) whose primary purpose is to create standardized pedagogical contents trough the aggregation and standardization of instructional resources in several formats that can be used later on a Learning Management System (LMS) supporting SCORM 1.2. The paper contains a brief introduction to the developed software, its system architecture, main features and several pedagogical advantages for its users
Quasi-spherical collapse with cosmological constant
The junction conditions between static and non-static space-times are studied
for analyzing gravitational collapse in the presence of a cosmological
constant. We have discussed about the apparent horizon and their physical
significance. We also show the effect of cosmological constant in the collapse
and it has been shown that cosmological constant slows down the collapse of
matter.Comment: 7 pages, No figures, RevTeX styl
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