Sonali Bhattacharya* Symbiosis Centre for Management and Human Resource Development, (Deemed University), India Submission: October 23, 2017; Published: January 17, 2018 *Corresponding author: Sonali Bhattacharya, Associate Professor, Symbiosis International (Deemed University), India, Tel: 91-20-22934304; Email: 0039 Introduction Distribution of runs and successions in various situations have been under considerable studies due to their applications to reliability theory of consecutive systems Grifitth [2]; Papastravridis & Sfkianakis [3], Sfkianakis, Kounias & Hillaris [4], Papastravridis & Koutras [5] & Cai [6], start-up demonstration tests [7], molecular biology [1], theory of radar detection, time sharing systems and quality control [8-12]. There are different ways of computations and enumeration of number of runs: 1. Feller [13] defined ways of counting the runs of exactly length k as counting the number from scratch everytime a run occurs. For example the sequence | SSS SFSSS SSS F contains 3 success runs of length 3 2. Goldstein [7] proposed the distribution of the number of success runs of at least length k until the n-th trial. In this way of counting the number of runs of length 3 (or more), in the above example contains 2 success runs of length 3 (or more) 3. Schwager [14] and Ling [15,16] studied the distributions on the number of overlapping runs of length k . In the enumeration scheme | SSS SFSSS SSS F contains 6 overlapping success runs of length 3. 4. Aki and Hirano [17] studied the distribution of success runs of exact length k . In the above example number of success runs of exact length 3 is 0. 5. Philippou[18] obtained the distribution of the number of trials until the first occurrence of consecutive k successes in Bernoulli trials with success probability as the geometric distribution of order ( ) ( ) , ; k k G xp In this paper, we have suggested alternative formulas for Binomial distribution of order k based on success runs of based on atleast length k by using Balls-into-cells technique with direct sampling scheme with replacement. The same result was extended by using inverse sampling scheme to obtain alternative formula for Geometric distribution of order k and negative Bionomial distribution of order k . Finally, using Polya Eggenberger sampling scheme we have obtained alternative formulas for Polya-Eggenberger distributions of order k and Inverse Polya-Eggenberger distributions of order k [19,20]. Lemma: The number ways of distributing r indistinguishable balls in n cells such that each cell has atmost ( 1) k balls is given as: ( ) ( ) ( ) 0 1 ; 1 1 r i k k i n r ik n F nr i n = + +  =   (Riordan 1958) (1) Binomial distribution of order k Let k n X the number of success runs of length at least k and r be the number of success in n Bernoulli trials and n r be the number of failures. Then, Theorem 1: ( ) ( ) 0 1 1 r xk a j k k n r xk j n r x n r PX x x j = = + + = = Abstract In this research paper, an attempt has been made to obtain alternative formulas for distributions of order k based on runs of at least length k. First by using binomial scheme and ‘balls-into-cells’ technique an alternative formula for distribution of binomial distribution of order k as defined by Goldstein [1]. Inverse Bionomial scheme was then used with ‘ball-into-cells technique to obtain alternate distribution of Geometric distribution of order k and negative binomial distribution of order k. The results were further extended to obtain Polya-Eggenberger distribution of order k and Inverse Polya-Eggenberger distributions of order k. All results were verified for exactness of probability. Keywords : Polya-Eggenberger sampling scheme; Distributions of order k; ‘Balls-into-cells’ technique Some Identities based on Success Runs of at Least Length k Biostat Biometrics Open Acc J 4(2): BBOAJ.MS.ID.555634 (2018) Review Article Volume 4 Issue 3 - January 2018 DOI: 10.19080/BBOAJ.2018.04.555634 Biostat Biometrics Open Acc J Copyright © All rights are reserved by Sonali Bhattacharya Biostatistics and Biometrics Open Access Journal ISSN: 2573-2633