Now showing 1 - 4 of 4
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    Approximations related to the sums of m-dependent random variables
    (01-06-2022)
    Kumar, Amit N.
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    Vellaisamy, P.
    In this paper, we mainly focus on the sums of non-negative integer-valued 1-dependent random variables and its approximation to the power series distribution. We first discuss some relevant results for power series distribution such as the Stein operator, uniform and non-uniform bounds on the solution of the Stein equation. Using Stein’s method, we obtain error bounds for the approximation problem considered. The obtained results can also be applied to the sums of m-dependent random variables via appropriate rearrangements of random variables. As special cases, we discuss two applications, namely, 2-runs and (k1,k2)-runs, and compare our bounds with existing bounds.
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    Improved bounds for approximations to compound distributions
    (01-02-2013) ;
    Vellaisamy, P.
    In this work, we consider compound negative binomial and compound Poisson approximations to the generalized Poisson-binomial distribution. We derive some total variation upper bounds which improve on the existing results in terms of the order of approximation. An application is also discussed. © 2012 Elsevier B.V.
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    Compound Poisson Approximation to Convolutions of Compound Negative Binomial Variables
    (22-10-2014) ;
    Vellaisamy, P.
    In this paper, the problem of compound Poisson approximation to the convolution of compound negative binomial distributions, under total variation distance, is considered. First, we obtain an error bound using the method of exponents and it is compared with existing ones. It is known that Kerstan’s method is more powerful in compound approximation problems. We employ Kerstan’s method to obtain better estimates, using higher-order approximations. These bounds are of higher-order accuracy and improve upon some of the known results in the literature. Finally, an interesting application to risk theory is discussed.
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    Publication
    On Stein operators for discrete approximations
    (01-11-2017) ;
    ÄŒius, Vydas ÄŒekanavi
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    Vellaisamy, P.
    In this paper, a new method based on probability generating functions is used to obtain multiple Stein operators for various random variables closely related to Poisson, binomial and negative binomial distributions. Also, the Stein operators for certain compound distributions, where the random summand satisfies Panjer's recurrence relation, are derived. A well-known perturbation approach for Stein's method is used to obtain total variation bounds for the distributions mentioned above. The importance of such approximations is illustrated, for example, by the binomial convoluted with Poisson approximation to sums of independent and dependent indicator random variables.