On an extension of the notion of Reedy category

We extend the classical notion of a Reedy category so as to allow non-trivial automorphisms. Our extension includes many important examples occuring in topology such as Segal's category Gamma, or the total category of a crossed simplicial group such as Connes' cyclic category Lambda. For any generalized Reedy category R and any cofibrantly generated model category E, the functor category E^R is shown to carry a canonical model structure of Reedy type

PROCEDURE FOR DETECTING ‘MORE NBU-NESS’ PROPERTY OF LIFE DISTRIBUTIONS

Testing the hypothesis of no ageing against positive ageing has been considered by many authors in the literature. However, very fewtests procedures for detecting whether a life distribution possesses ‘more positive ageng’ than the other distribution are developed.Hollander, Park and Proschan(1986) proposed a test procedure to detect ‘More NBUness’ property of life distributions. Pandit and Gudaganavar(2009) developeda procedure which is an improvementover the test due to Hollander, Park and Proschan(1986). In this paper, a test is developed to decide whether onelife distribution possesses more ‘new better than used’ (NBU)property than does another life distribution. The asymptotic performance of the test procedure is evaluated interms of Pitman asymptotic relative efficiency. It is found that new test performs betterthan the tests in the literature

A Nonparametric Control Chart for Location Based on Sub-Samples of Size Two

Control charts are widely used in statistical process control to detect changes in a production process and for monitoring a process to make sure that it is in control. In conventional statistical process control, the pattern of chance causes is often assumed to follow normal distribution. It is well known that the assumption of normality or any specific parametric form for the process distribution is too restrictive. In such situations, distribution-free or nonparametric control charts can serve the purpose better. In this paper, distribution-free control charts are developed based on a class of one-sample test statistics with sub-samples of size two due to Mehra, Prasad and Madhava Rao (Austral. J. Statist. 32: 373392, 1990). The control charts based on their statistic (-chart) are easy to understand and to use. The performance of the proposed procedures is studied through the average run length, which is the expected number of samples required by the procedure to signal out of control. It is observed that the performance of the proposed chart is better than the existing charts in the literature

TEST PROCEDURES FOR DETECTING ‘MORE NBUNESS’ PROPERTY OF LIFE DISTRIBUTIONS

Testing the hypothesis of no ageing against positive ageing has been considered by many authors in the literature. However, very few tests procedures for detecting whether a life distribution possesses ‘more positive ageng’ than the other distribution are developed. Hollander, Park and Proschan (1986) proposed a test procedure to detect ‘More NBU-ness’ property of life distributions, Pandit and Gudaganavar (2009) developed a procedure which is an improvement over the test due to Hollander, Park and Proschan (1986). In this paper, a test is developed to decide whether one life distribution possesses more ‘new better than used’ (NBU) property than does another life distribution. The asymptotic performance of the tes

Turquie. Elections générales de juin 2011 : acteurs en lice et enjeux sociaux

Consultable sur : http://www.ires-fr.org/images/files/Chronique/chronique130/c130-3.pdfInternational audienc

Turquie. Rigueur budgétaire, austérité pour les travailleurs : encore et toujours ?

Consultable sur : http://www.ires-fr.org/images/files/Chronique/chronique127/c127-11.pdfInternational audienc

Anomaly-Free Sets of Fermions

We present new techniques for finding anomaly-free sets of fermions. Although the anomaly cancellation conditions typically include cubic equations with integer variables that cannot be solved in general, we prove by construction that any chiral set of fermions can be embedded in a larger set of fermions which is chiral and anomaly-free. Applying these techniques to extensions of the Standard Model, we find anomaly-free models that have arbitrary quark and lepton charges under an additional U(1) gauge group.Comment: 21 (+1) page