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1.
From a logical viewpoint, object is never defined, even by a negative definition. This paper is a theoretical contribution about object using a new constructivist logical approach called Logic of Determination of Objects founded on a basic operation, called determination. This new logic takes into account cognitive problems such as the inheritance of properties by non typical occurrences or by indeterminate atypical objects in opposition to prototypes that are typical completely determinate objects. We show how extensional classes, intensions, more and less determined objects, more or less typical representatives of a concept and prototypes are defined and organized, using a determination operation that constructs a class of indeterminate objects from an object representation of a concept called typical object.  相似文献   

2.
This article is dedicated to one of the greatest mathematicians of our time: V.I. Arnold, who died suddenly Thursday, June 3, 2010 in France. Integrable hamiltonian systems are nonlinear ordinary differential equations described by a hamiltonian function and possessing sufficiently many independent constants of motion in involution. The regular compact level manifolds defined by the intersection of the constants of motion are diffeomorphic to a real torus on which the motion is quasi-periodic as a consequence of the following purely differential geometric fact: a compact and connected n-dimensional manifold on which there exist n vector fields which commute and are independent at every point is diffeomorphic to an n-dimensional real torus and each vector field will define a linear flow there. We make a careful study of the connection with the concept of completely integrable systems and we apply the methods to several problems.  相似文献   

3.
For G, a symplectic or orthogonal p-adic group (not necessarily split) or an inner form of a general linear p-adic group, we compute the endomorphism algebras of some induced projective generators à la Bernstein of the category of smooth representations of G and show that these algebras are isomorphic to the semi-direct product of a Hecke algebra with parameters by a finite group algebra. Our strategy and parts of our intermediate results apply to a general reductive connected p-adic group.  相似文献   

4.
5.
??Inspired by intuitive meanings of truncated power basis's coefficients, the local penalization based on range's linear decreasing function is given in penalized spline regression model. This method gives less penalization to fitting curve where data is with more volatility, which makes fitted curve controls tradeoff between goodness-of-fit and smoothness better. Simulations show that regression models with local penalized spline obtain lower information rules' scores than global penalized spline when the data is with heteroskedasticity.  相似文献   

6.
In this paper, considering of the special geometry of compositional data, two new methods for estimating missing values in compositional data are introduced. The first method uses the mean in the simplex space which mainly finds the-nearest neighbor procedure based on the Aitchison distance, combining with two basic operations on the simplex, perturbation and powering. As a second proposal the principal component regression imputation method is introduced which initially starts from the result of the proposed the mean in the simplex. The method uses ilr transformation to transform the compositional data set, and then uses principal component regression in a transformed space. The proposed methods are tested on real data and simulated data sets, the results show that the proposed methods work well.  相似文献   

7.
??When the data has heavy tail feature or contains outliers, conventional variable selection methods based on penalized least squares or likelihood functions perform poorly. Based on Bayesian inference method, we study the Bayesian variable selection problem for median linear models. The Bayesian estimation method is proposed by using Bayesian model selection theory and Bayesian estimation method through selecting the Spike and Slab prior for regression coefficients, and the effective posterior Gibbs sampling procedure is also given. Extensive numerical simulations and Boston house price data analysis are used to illustrate the effectiveness of the proposed method.  相似文献   

8.
In this paper, for a kind of risk models with heavy-tailed and delayed claims, we derive the asymptotics of the infinite-time ruin probability and the uniform asymptotics of the finite-time ruin probability. The numerical simulation results are also presented. The results of theoretical analysis and numerical simulation show that the influence of the delay for the claim payment is nearly negligible to the ruin probability when the initial capital and running-time are all large.  相似文献   

9.
For linear quantile regression model, this paper proves that the test statistics, besed on smoothed empirical likelihood (SEL) method and least absolute deviation (LAD) method, both converge weakly to a noncentral Chi-square distribution under the local alternatives $H_1:\beta=\beta_0+a_n$, where $\beta$ is the true parameter. Simulation results show that the SEL method is more efficient than the LAD method.  相似文献   

10.
??In this paper, we prove the existence and uniqueness of solutions for reflected backward stochastic differential equations driven by a Levy process, in which the reflecting barriers are just right continuous with left limits whose jumps are arbitrary. To derive the above results, the monotonic limit theorem of Backward SDE associated with Levy process is established.  相似文献   

11.
Let M be a compact K?hler manifold equipped with a Hamiltonian action of a compact Lie group G. Guillemin and Sternberg (Invent Math 67:515?C538, 1982, no. 3), showed that there is a geometrically natural isomorphism between the G-invariant quantum Hilbert space over M and the quantum Hilbert space over the symplectic quotient M //G. This map, though, is not in general unitary, even to leading order in ${\hslash}$ . Hall and Kirwin (Commun Math Phys 275:401?C422, 2007, no. 2), showed that when the metaplectic correction is included, one does obtain a map which, while not in general unitary for any fixed ${\hslash}$ , becomes unitary in the semiclassical limit ${\hslash\rightarrow0}$ (cf. the work of Ma and Zhang (C R Math Acad Sci Paris 341:297?C302, 2005, no. 5), and (Astérisque No. 318:viii+154, 2008). The unitarity of the classical Guillemin?CSternberg map and the metaplectically corrected analogue is measured by certain functions on the symplectic quotient M //G. In this paper, we give precise expressions for these functions, and compute complete asymptotic expansions for them as ${\hslash\rightarrow0}$ .  相似文献   

12.
In this paper, we introduce a new algorithm for computing a set of generators for the syzygies on a sequence of polynomials. For this, we extend a given sequence of polynomials to a Gr?bner basis using Faugère??s F5 algorithm (A new efficient algorithm for computing Gr?bner bases without reduction to zero (F 5). ISSAC, ACM Press, pp 75?C83, 2002). We show then that if we keep all the reductions to zero during this computation, then at termination (by adding principal syzygies) we obtain a basis for the module of syzygies on the input polynomials. We have implemented our algorithm in the computer algebra system Magma, and we evaluate its performance via some examples.  相似文献   

13.
14.
Loynes?? distribution, which characterizes the one dimensional marginal of the stationary solution to Lindley??s recursion, possesses an ultimately exponential tail for a large class of increment processes. If one can observe increments but does not know their probabilistic properties, what are the statistical limits of estimating the tail exponent of Loynes?? distribution? We conjecture that in broad generality a consistent sequence of non-parametric estimators can be constructed that satisfies a large deviation principle. We present rigorous support for this conjecture under restrictive assumptions and simulation evidence indicating why we believe it to be true in greater generality.  相似文献   

15.
We provide a semilocal convergence analysis for Newton-like methods of ??bounded deterioration?? in a Banach space setting. We establish tighter error bounds on the distances involved, and a more precise information on the location of the solution, under the same or weaker hypotheses than before (Argyros, Acta Math. Sin. (Engl. Ser.), 23:2087?C2096, 2007; Deuflhard, Newton methods for nonlinear problems. Affine invariance and adaptive algorithms, Springer Series in Computational Mathematics, vol. 35. Springer, Berlin, 2004; Ezquerro and Hern??ndez, IMA J. Numer. Anal., 22:187?C205, 2002) using recurrent functions. Numerical examples are also provided involving polynomial, integral, and differential equations.  相似文献   

16.
Once-holed tori are the most primitive noncompact Riemann surfaces of positive genus, and can be used to measure the sizes of handles of Riemann surfaces of positive genus. We study some families of once-holed tori that are conformally embedded in target Riemann surfaces of conformal mappings of a given noncompact Riemann surface of genus one, and correct some results given in Masumoto (Math. Z. 257:453?C464, 2007).  相似文献   

17.
Let G be a locally compact abelian group (LCA group) and ?? be an open, 0-symmetric set. Let F:= F(??) be the set of all continuous functions f: G ?? ? which are supported in ?? and are positive definite. The Turán constant of ?? is then defined as $$ \mathcal{T}(\Omega ): = \sup \left\{ {\int_\Omega {f:f \in \mathcal{F}} (\Omega ),f(0) = 1} \right\} $$ . Mihalis Kolountzakis and the author has shown that structural properties ?? like spectrality, tiling or packing with a certain set ?? ?? of subsets ?? in finite, compact or Euclidean (i.e., ? d ) groups and in ? d yield estimates of T (??). However, in these estimates some notion of the size, i.e., density of ?? played a natural role, and thus in groups where we had no grasp of the notion, we could not accomplish such estimates. In the present work a recent generalized notion of asymptotic uniform upper density is invoked, allowing a more general investigation of the Turán constant in relation to the above structural properties. Our main result extends a result of Arestov and Berdysheva, (also obtained independently and along different lines by Kolountzakis and the author), stating that convex tiles of a Euclidean space necessarily have $$ \mathcal{T}_{\mathbb{R}^d } (\Omega )\left| \Omega \right|/2^d $$ . In our extension ? d could be replaced by any LCA group, convexity is considerably relaxed to ?? being a difference set, and the condition of tiling is also relaxed to a certain packing type condition and positive asymptotic uniform upper density of the set ??. Also our goal is to give a more complete account of all the related developments and history, because until now an exhaustive overview of the full background of the so-called Turán problem was not delivered.  相似文献   

18.
Letbe a sequence of real-valued random variables and be other random variables which are independent of the form sequence. Suppose that are pairwise generalized negatively orthant dependent with heavy tails under the condition that are independent or associated, some asymptotic formulas are established.  相似文献   

19.
20.
In order to solve the problem of testing multidimensional diffusion models, we develop a test statistic based on Multi-Dimensional Tail Condition Expectations (CTEs). Although it is almost impossible to estimate the transition density matrix of a multidimensional diffusion model directly, the transition density of each component can be estimated and each component can be combined by the CTE to establish a true multidimensional statistics. Finally, the performance of the test is evaluated through simulation.  相似文献   

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