On closeness of two discrete weighted sums        
        
    
        Volume 5, Issue 2 (2018), pp. 207–224
            
    
                    Pub. online: 21 May 2018
                    
        Type: Research Article
            
                
             Open Access
Open Access
        
            
    
                Received
1 February 2018
                                    1 February 2018
                Revised
16 April 2018
                                    16 April 2018
                Accepted
27 April 2018
                                    27 April 2018
                Published
21 May 2018
                    21 May 2018
Abstract
The effect that weighted summands have on each other in approximations of $S={w_{1}}{S_{1}}+{w_{2}}{S_{2}}+\cdots +{w_{N}}{S_{N}}$ is investigated. Here, ${S_{i}}$’s are sums of integer-valued random variables, and ${w_{i}}$ denote weights, $i=1,\dots ,N$. Two cases are considered: the general case of independent random variables when their closeness is ensured by the matching of factorial moments and the case when the ${S_{i}}$ has the Markov Binomial distribution. The Kolmogorov metric is used to estimate the accuracy of approximation.
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