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Article
Publication date: 6 September 2011

Muhammad Aslam, Abdur Razzaque Mughal and Munir Ahmad

The purpose of this paper is to propose the group acceptance sampling plans for when the lifetime of the submitted product follows the Pareto distribution.

Abstract

Purpose

The purpose of this paper is to propose the group acceptance sampling plans for when the lifetime of the submitted product follows the Pareto distribution.

Design/methodology/approach

The single‐point approach (only consumer's risk) is used to find the plan parameter of the proposed plan for specified values of consumer's risk, producer's risk, acceptance number, number of testers and experiment time.

Findings

Tables are constructed using the Poisson and the weighted Poisson distribution. Extensive tables are provided for practical use.

Research limitations/implications

The tables in this paper can be used only when the lifetime of a product follows the Pareto distribution of 2nd kind.

Practical implications

The result can be used to test the product to save cost and time of the experiment. The use of the weighted Poisson distribution provides the less group size (sample size) as than the plans in the literature.

Social implications

By implementing the proposed plan, the experiment cost can be minimized.

Originality/value

The novelty of this paper is that Poisson and the weighted Poisson distributions are used to find the plan parameter of the proposed plan instead of the binomial distribution when the lifetime of submitted product follows the Pareto distribution of 2nd kind.

Details

International Journal of Quality & Reliability Management, vol. 28 no. 8
Type: Research Article
ISSN: 0265-671X

Keywords

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Article
Publication date: 30 March 2012

Akbar A. Javadi, Asaad Faramarzi and Raziyeh Farmani

Auxetic materials differ from conventional materials by the manner in which they respond to stretching; they tend to get fatter when stretched, resulting in a negative…

Abstract

Purpose

Auxetic materials differ from conventional materials by the manner in which they respond to stretching; they tend to get fatter when stretched, resulting in a negative Poisson's ratio. The purpose of this paper is to present a numerical methodology for design of microstructure of 2D and 3D auxetic materials with a wide range of different negative Poisson's ratios.

Design/methodology/approach

The proposed methodology is based on a combination of finite element method and a genetic algorithm. The problem is formulated as an optimization problem of finding microstructures with prescribed behavioral requirements. Different microstructures are generated and evolved using the genetic algorithm and the behavior of each microstructure is analyzed using the finite element method to evaluate its fitness in competition with other generated structures.

Findings

Numerical examples show that it is possible to design a large number of new auxetic materials, each with a different value of negative Poisson's ratio.

Originality/value

The proposed methodology can be used as an effective method to tailor new materials with prescribed values of negative (or positive) Poisson's ratio. The methodology can also be used to optimize other material properties.

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Article
Publication date: 1 November 2002

Fuang‐Yuan Huang, Biing‐Hwa Yan and Der‐Uei Yang

To investigate the relation between the Poisson's ratio of a re‐entrant honeycomb structure by varying the micropolar material constants such as micropolar Young's modulus…

Abstract

To investigate the relation between the Poisson's ratio of a re‐entrant honeycomb structure by varying the micropolar material constants such as micropolar Young's modulus Em, micropolar Poisson's ratio Vm, characteristic length l, coupling factor N, and micropolar elastic constants in accordance with the micropolar elastic restrictions, a 2‐D triangular finite element formulation including an extra degree of freedom was derived on the basis of Eringen's micropolar elasticity theory by using a linear triangular element. The effects on the structural Poisson's ratio of the honeycomb structure are studied in detail.

Details

Engineering Computations, vol. 19 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 1 November 2001

Der‐Uei Yang and Fuang‐Yuan Huang

Based on Eringen’s micropolar elasticity theory (MET), a two‐dimensional finite element formulation including one extra degree of freedom is derived by using a linear…

Abstract

Based on Eringen’s micropolar elasticity theory (MET), a two‐dimensional finite element formulation including one extra degree of freedom is derived by using a linear triangular element, and a corresponding computer program is also developed. By varying the technical constants such as micropolar Young’s modulus Em, micropolar Poisson’s ratio νm, characteristic length l, coupling factor N, and micropolar elastic constants in accordance with the micropolar elastic restrictions, their effects on the Poisson’s ratio of the rectangular plate are studied in detail.

Details

Engineering Computations, vol. 18 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 11 January 2018

Qin Zhang and P.B. Seetharaman

The purpose of this paper is to propose a method to help firms assess lifetime profitability of customers whose buying behaviors are characterized by purchasing cycles…

Abstract

Purpose

The purpose of this paper is to propose a method to help firms assess lifetime profitability of customers whose buying behaviors are characterized by purchasing cycles, which are determined by both intrinsic purchasing cycles and cumulative effects of firms’ marketing solicitations.

Design/methodology/approach

This paper first proposes a probability model to predict customers’ responses to firms’ marketing solicitations in which a customer’s inter-purchase times are assumed to follow a Poisson distribution, whose parameters vary across customers and follow a gamma distribution. The paper then proposes a customer profitability scoring model that uses customers’ responses as an input to assess their lifetime profitability at a given point of time.

Findings

The paper illustrates the proposed method using individual-level purchasing data of 529 customers from a catalog firm. The paper shows that the proposed model outperforms the benchmark model in terms of both explaining and predicting customers’ purchases. The paper also demonstrates significant profit consequences to the firm if incorrect methods are used instead of the proposed method.

Practical implications

The proposed method can help firms select or eliminate customers based on their lifetime profitability so that firms can focus their marketing efforts in a more targeted manner to increase total profits.

Originality/value

The proposed Gamma-Poisson probability model and the profitability scoring method are easy to implement due to the attractive conjugacy property. It is valuable for firms’ customer relationship management applications from the standpoint of making customer selection and inventory management decisions.

Details

Marketing Intelligence & Planning, vol. 36 no. 2
Type: Research Article
ISSN: 0263-4503

Keywords

Content available
Article
Publication date: 30 September 2019

Victor Motta

The purpose of this study is to account for a recent non-mainstream econometric approach using microdata and how it can inform research in business administration. More…

Abstract

Purpose

The purpose of this study is to account for a recent non-mainstream econometric approach using microdata and how it can inform research in business administration. More specifically, the paper draws from the applied microeconometric literature stances in favor of fitting Poisson regression with robust standard errors rather than the OLS linear regression of a log-transformed dependent variable. In addition, the authors point to the appropriate Stata coding and take into account the possibility of failing to check for the existence of the estimates – convergency issues – as well as being sensitive to numerical problems.

Design/methodology/approach

The author details the main issues with the log-linear model, drawing from the applied econometric literature in favor of estimating multiplicative models for non-count data. Then, he provides the Stata commands and illustrates the differences in the coefficient and standard errors between both OLS and Poisson models using the health expenditure dataset from the RAND Health Insurance Experiment (RHIE).

Findings

The results indicate that the use of Poisson pseudo maximum likelihood estimators yield better results that the log-linear model, as well as other alternative models, such as Tobit and two-part models.

Originality/value

The originality of this study lies in demonstrating an alternative microeconometric technique to deal with positive skewness of dependent variables.

Details

RAUSP Management Journal, vol. 54 no. 4
Type: Research Article
ISSN: 2531-0488

Keywords

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Article
Publication date: 1 August 1997

Richard L. Henshel

Briefly reviews the standard Poisson distribution and then examines a set of derivative, modified Poisson distributions for testing hypotheses derived from positive…

Abstract

Briefly reviews the standard Poisson distribution and then examines a set of derivative, modified Poisson distributions for testing hypotheses derived from positive deviation‐amplifying feedback models, which do not lend themselves to ordinary statistically based hypothesis testing. The “reinforcement” or “contagious” Poisson offers promise for a subset of such models, in particular those models with data in the form of rates (rather than magnitudes). The practical difficulty lies in distinguishing reinforcement effects from initial heterogeneity, since both can form negative binomial distributions, with look‐alike data. Illustrates these difficulties, and also opportunities, for various feedback models employing the self‐fulfilling prophecy, and especially for confidence loops, which incorporate particular self‐fulfilling prophecies as part of a larger dynamic process. Describes an actual methodology for testing hypotheses regarding confidence loops with the aid of a “reinforcement” Poisson distribution, as well as its place within sociocybernetics.

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Article
Publication date: 4 January 2013

Kandasamy Subramani and Venugopal Haridoss

The purpose of this paper is to present the single sampling attribute plan for given acceptance quality level (AQL) and limiting quality level (LQL) involving minimum sum…

Abstract

Purpose

The purpose of this paper is to present the single sampling attribute plan for given acceptance quality level (AQL) and limiting quality level (LQL) involving minimum sum of risks using weighted Poisson distribution.

Design/methodology/approach

For the given AQL and LQL, sum of producer's and consumer's risks have been attained. Based on weighted Poisson distribution, the sum of these risks has been arrived at, along with the acceptance number and the rejection number. Also, the operating characteristic function for the single sampling attribute sampling plan, using weighted Poisson distribution, has been derived.

Findings

In the final inspection, the producer and the consumer represent the same party. So, the sum these two risks should be minimized. In this paper, the sum of risks has been tabulated using weighted Poisson distribution for different operating ratios. These tabulated values are comparatively less than the sum of risks derived using Poisson distribution.

Originality/value

The sampling plan presented in this paper is particularly useful for testing the quality of finished products in shop floor situations.

Details

International Journal of Quality & Reliability Management, vol. 30 no. 1
Type: Research Article
ISSN: 0265-671X

Keywords

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Article
Publication date: 31 December 2015

Venugopal Haridoss and Kandasamy Subramani

– The purpose of this paper is to present the optimal double sampling attribute plan using the weighted Poisson distribution.

Abstract

Purpose

The purpose of this paper is to present the optimal double sampling attribute plan using the weighted Poisson distribution.

Design/methodology/approach

For the given AQL and LQL, sum of producer’s and consumer’s risks have been attained. Based on the weighted Poisson distribution, the sum of these risks has been optimized.

Findings

In the final inspection, the producer and the consumer represent the same party. So, the sum these two risks should be minimized. In this paper, the sum of risks has been tabulated using the weighted Poisson distribution for different operating ratios. These tabulated values are comparatively less than the sum of risks derived using Poisson distribution.

Originality/value

The sampling plan presented in this paper is particularly useful for testing the quality of finished products in shop floor situations.

Details

International Journal of Quality & Reliability Management, vol. 33 no. 1
Type: Research Article
ISSN: 0265-671X

Keywords

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Article
Publication date: 5 June 2007

Stephen J. Bensman

The purpose of this article is to analyze the historical significance of Donald J. Urquhart, who established the National Lending Library for Science and Technology (NLL…

Abstract

Purpose

The purpose of this article is to analyze the historical significance of Donald J. Urquhart, who established the National Lending Library for Science and Technology (NLL) that later was merged into the British Library Lending Division (BLLD), now called the British Library Document Supply Centre (BLDSC).

Design/methodology/approach

The paper presents a short history of the probabilistic revolution, particularly as it developed in the UK in the form of biometric statistics due to Darwin's theory of evolution. It focuses on the overthrow of the normal paradigm, according to which frequency distributions in nature and society conform to the normal law of error. The paper discusses the importance of the Poisson distribution and its utilization in the construction of stochastic models that better describe reality. Here the focus is on the compound Poisson distribution in the form of the negative binomial distribution (NBD). The paper then shows how Urquhart extended the probabilistic revolution to librarianship by using the Poisson as the probabilistic model in his analyses of the 1956 external loans made by the Science Museum Library (SML) as well as in his management of the scientific and technical (sci/tech) journal collection of the NLL. Thanks to this, Urquhart can be considered as playing a pivotal role in the creation of bibliometrics or the statistical bases of modern library and information science. The paper relates how Urquhart's son and daughter‐in‐law, John A. and Norma C. Urquhart, completed Urquhart's probabilistic breakthrough by advancing for the first time the NBD as the model for library use in a study executed at the University of Newcastle upon Tyne, connecting bibliometrics with biometrics. It concludes with a discussion of Urquhart's Law and its probabilistic implications for the use of sci/tech journals in a library system.

Findings

By being the first librarian to apply probability to the analysis of sci/tech journal use, Urquhart was instrumental in the creation of modern library and information science. His findings force a probabilistic re‐conceptualization of sci/tech journal use in a library system that has great implications for the transition of sci/tech journals from locally held paper copies to shared electronic databases.

Originality/value

Urquhart's significance is considered from the perspective of the development of science as a whole as well as library and information science in particular.

Details

Interlending & Document Supply, vol. 35 no. 2
Type: Research Article
ISSN: 0264-1615

Keywords

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