3,611 research outputs found

    Parameter estimation in pair hidden Markov models

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    This paper deals with parameter estimation in pair hidden Markov models (pair-HMMs). We first provide a rigorous formalism for these models and discuss possible definitions of likelihoods. The model being biologically motivated, some restrictions with respect to the full parameter space naturally occur. Existence of two different Information divergence rates is established and divergence property (namely positivity at values different from the true one) is shown under additional assumptions. This yields consistency for the parameter in parametrization schemes for which the divergence property holds. Simulations illustrate different cases which are not covered by our results.Comment: corrected typo

    Conservation laws for self-adjoint first order evolution equations

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    In this work we consider the problem on group classification and conservation laws of the general first order evolution equations. We obtain the subclasses of these general equations which are quasi-self-adjoint and self-adjoint. By using the recent Ibragimov's Theorem on conservation laws, we establish the conservation laws of the equations admiting self-adjoint equations. We illustrate our results applying them to the inviscid Burgers' equation. In particular an infinite number of new symmetries of these equations are found and their corresponding conservation laws are established.Comment: This manuscript has been accepted for publication in Journal of Nonlinear Mathematical Physic

    Group Analysis of the Novikov Equation

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    We find the Lie point symmetries of the Novikov equation and demonstrate that it is strictly self-adjoint. Using the self-adjointness and the recent technique for constructing conserved vectors associated with symmetries of differential equations, we find the conservation law corresponding to the dilations symmetry and show that other symmetries do not provide nontrivial conservation laws. Then we investigat the invariant solutions

    About the progressive tax system of labor remuneration in Russia

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    © 2014 Canadian Center of Science and Education. All rights reserved. This paper presents the results of research aimed at improvement of the taxation of wages in Russia. It analyses the problem of determining the progressive income tax scale as being a more socially equitable than the current flat rate in Russia with 13% tax rate on income. Proposed tax scale of tax rates exempts the poor citizens from income tax, shifting the tax burden from the poor to the rich. In accordance with the principle of redistribution that leads to a reduction in income inequality in Russia. The most important source of budget revenues are taxes. In Russia, as in most countries, the tax on personal income (referred to as PIT) is one of the main sources of budget revenues. Its share of the budget is directly dependent on the level of economic development. This is one of the most popular taxes in the world payable on personal incomes. PIT is linked to consumption, and it can either stimulate consumption or reduce it. Therefore, the main challenge of income taxation is to achieve optimal balance between economic efficiency and social justice of the tax. In other words, such tax is required, which would provide the maximum equitable redistribution of income with minimal damage to the interests of taxpayers from taxation. Analysis of tax on personal income shows that it, as well as the whole tax system in the Russian Federation is constantly developing

    A symmetry classification for a class of (2+1)-nonlinear wave equation

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    In this paper, a symmetry classification of a (2+1)(2+1)-nonlinear wave equation utt−f(u)(uxx+uyy)=0u_{tt}-f(u)(u_{xx}+u_{yy})=0 where f(u)f(u) is a smooth function on uu, using Lie group method, is given. The basic infinitesimal method for calculating symmetry groups is presented, and used to determine the general symmetry group of this (2+1)(2+1)-nonlinear wave equation

    Extreme value statistics and return intervals in long-range correlated uniform deviates

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    We study extremal statistics and return intervals in stationary long-range correlated sequences for which the underlying probability density function is bounded and uniform. The extremal statistics we consider e.g., maximum relative to minimum are such that the reference point from which the maximum is measured is itself a random quantity. We analytically calculate the limiting distributions for independent and identically distributed random variables, and use these as a reference point for correlated cases. The distributions are different from that of the maximum itself i.e., a Weibull distribution, reflecting the fact that the distribution of the reference point either dominates over or convolves with the distribution of the maximum. The functional form of the limiting distributions is unaffected by correlations, although the convergence is slower. We show that our findings can be directly generalized to a wide class of stochastic processes. We also analyze return interval distributions, and compare them to recent conjectures of their functional form

    Integrability of Lie systems through Riccati equations

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    Integrability conditions for Lie systems are related to reduction or transformation processes. We here analyse a geometric method to construct integrability conditions for Riccati equations following these approaches. This approach provides us with a unified geometrical viewpoint that allows us to analyse some previous works on the topic and explain new properties. Moreover, this new approach can be straightforwardly generalised to describe integrability conditions for any Lie system. Finally, we show the usefulness of our treatment in order to study the problem of the linearisability of Riccati equations.Comment: Corrected typo

    Morphological and syntactical features of adjectives in English and Tatar participles

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    The article is devoted to the comparative analysis of the Tatar and English participles. The paper substantiates the position that the correlation and comparison of the languages allows to define common and specific features. The paper presents analysis of adjectival features of participles in the English and Tatar languages in morphological and syntactical aspects. The authors ascertain that despite typological distinctions of translation equivalents, certain similarities of their structural organization and component structure are revealed.Keywords and phrases: linguistics, language, speech, participles, English, Tatar, translation,verbals, contrastive linguistic

    Invariants of differential equations defined by vector fields

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    We determine the most general group of equivalence transformations for a family of differential equations defined by an arbitrary vector field on a manifold. We also find all invariants and differential invariants for this group up to the second order. A result on the characterization of classes of these equations by the invariant functions is also given.Comment: 13 page

    Lie group analysis of a generalized Krichever-Novikov differential-difference equation

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    The symmetry algebra of the differential--difference equation u˙n=[P(un)un+1un−1+Q(un)(un+1+un−1)+R(un)]/(un+1−un−1),\dot u_n = [P(u_n)u_{n+1}u_{n-1} + Q(u_n)(u_{n+1}+u_{n-1})+ R(u_n)]/(u_{n+1}-u_{n-1}), where PP, QQ and RR are arbitrary analytic functions is shown to have the dimension 1 \le \mbox{dim}L \le 5. When PP, QQ and RR are specific second order polynomials in unu_n (depending on 6 constants) this is the integrable discretization of the Krichever--Novikov equation. We find 3 cases when the arbitrary functions are not polynomials and the symmetry algebra satisfies \mbox{dim}L=2. These cases are shown not to be integrable. The symmetry algebras are used to reduce the equations to purely difference ones. The symmetry group is also used to impose periodicity un+N=unu_{n+N}=u_n and thus to reduce the differential--difference equation to a system of NN coupled ordinary three points difference equations
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