Acceptance Sampling Plans from Life Tests Based on Percentiles of New Weibull–Pareto Distribution with Application to Breaking Stress of Carbon Fibers Data

In this paper, acceptance sampling plans (ASPs) are proposed for the new Weibull-Pareto distribution (NWPD) percentiles assuming truncated life tests at a pre-determined time. The minimum sample sizes essential to assert the specified percentile are calculated for a given consumer’s risk. The operating characteristic function values of the developed ASPs and producer’s risk are provided. A real data set related to the breaking stress of carbon fibers data are presented for illustration.

Reliability Sampling Procedure For High Priced Products

Life testing for very high priced products with least of sample size can be done using the procedure of sampling plan designed in this paper. The required sample size for various of operating characteristic function using new design procedure is obtained using program in OCTAVE based on Lomaxdistribution and is compared with sample size obtained based on exponential distribution.

Economic Determination of Modified Multiple Dependent State Sampling Plan under Some Lifetime Distributions

In this paper, the modification of multiple dependent state sampling plan is proposed and designed for assuring a mean lifetime of the products under Birnbaum–Saunders distribution and Weibull distribution. The optimal parameters of the proposed plan are determined based on two points on the operating characteristic curve approach. Different combinations of producer’s risk and consumer’s risk are considered for plan parameters determination. The efficacy of the proposed plan is compared with those of other existing sampling plans using an average sample number and operating characteristic function. The economic designing of the proposed plan is also considered and the comparative study is done based on the total cost of the inspection.

A Research Algorithm to Sentence the Lots for Costly or Destructive Products in Mixed Quality Characteristics

This paper deals with the new operating procedure of Acceptance Sampling Plans for costly or destructive products when the incoming lots have mixed quality characteristics. The Operating Characteristic function and other associated measures of the plan are derived and provided. The procedure is given and designing of sampling plan are indexed through standard quality levels. Tables are constructed for easy selection of the plan.Illustrations are also provided.

Improved binomial and Poisson approximations to the Type-A operating characteristic function

PurposeIn acceptance sampling, the hypergeometric operating characteristic (OC) function (so called type-A OC) is used to be approximated by the binomial or Poisson OC function, which actually reduce computational effort, but do not provide suffcient approximation results. The purpose of this paper is to examine binomial- and Poisson-type approximations to the hypergeometric distribution, in order to find a simple but accurate approximation that can be successfully applied in acceptance sampling.Design/methodology/approachThe authors present a new binomial-type approximation for the type-A OC function, and derive its properties. Further, the authors compare this approximation via an extensive numerical study with other common approximations in terms of variation distance and relative efficiency under various conditions on the parameters including limiting cases.FindingsThe introduced approximation generates best numerical results over a wide range of parameter values, and ensures arithmetic simplicity of the binomial distribution and high accuracy to meet requirements regarding acceptance sampling problems. Additionally, it can considerably reduce the computational effort in relation to the type-A OC function and therefore is strongly recommended for calculating sampling plans.Originality/valueThe newly presented approximation provides a remarkably close fit to the type-A OC function, is discrete and needs no correction for continuity, and is skewed in the same direction by roughly the same amount as the exact OC. Due to less factorials, this OC in general involves lower powers than the type-A OC function. Moreover, the binomial-type approximation is easy to fit to the conventional statistical computing packages.

A Two-Parameter Quasi Lindley Distribution in Acceptance Sampling Plans from Truncated Life Tests

In this paper, acceptance sampling plans are developed when the life test is truncated at a pre-assigned time. For different acceptance numbers, confidence levels and values of the ratio of the fixed experiment time to the specified average life time, the minimum sample sizes required to ensure the specified average life are calculate assuming that the life time variate of the test units follows a two-parameter Quasi Lindley distribution (QLD(2)). The operating characteristic function values of the new sampling plans and the corresponding producer's risk are presented.

Inspection tables for single acceptance sampling with crisp and fuzzy formulation of quality limits

Purpose The purpose of this paper is to construct innovative exact and approximative sampling plans for acceptance sampling in statistical quality control. These sampling plans are determined for crisp and fuzzy formulation of quality limits, various lot sizes and common α- and β-levels. Design/methodology/approach The authors use generalized fuzzy hypothesis testing to determine sampling plans with fuzzified quality limits. This test method allows a consideration of the indifference zone related to expert opinion or user priorities. In addition to the exact sampling plans calculated with the hypergeometric operating characteristic function, the authors consider approximative sampling plans using a little known, but excellent operating characteristic function. Further, a comprehensive sensitivity analysis of calculated sampling plans is performed, in order to examine how the inspection effort depends on crisp and fuzzy formulation of quality limits, the lot size and specifications of the producer’s and consumer’s risks. Findings The results related the parametric sensitivity analysis of the calculated sampling plans and the conclusions regarding the approximation quality provide the user a comprehensive basis for a direct implementation of the sampling plans in practice. Originality/value The constructed sampling plans ensure the simultaneous control of producer’s and consumer’s risks with the smallest possible inspection effort on the one hand and a consideration of expert opinion or user priorities on the other hand.

The transmuted generalized inverse Weibull distribution in acceptance sampling plans based on life tests

In this paper, designing of acceptance sampling plans for the truncated life test is suggested by assuming that the product lifetime follows transmuted generalized inverse Weibull distribution (TGIWD). For various values of the TGIWD parameters, the minimum sample sizes required to ensure the specified mean life are obtained, as well as the operating characteristic function values and producer’s risk of the suggested sampling plan are calculated. The results are explained by numerical examples and an application of real data is considered for illustration.

Acceptance Sampling Plans Based on Truncated Lifetime Tests for Transmuted Inverse Rayleigh Distribution

In this paper, we propose acceptance sampling plans for transmuted inverse Rayleigh distribution when the lifetime time is truncated at a predetermined level. We consider various characteristics of the acceptance sampling plans such as confidence levels, acceptance numbers, ratio of the experimental time to such a specified average, minimum requisite sample size to affirm a certain mean lifetime assuming transmuted inverse Rayleigh distribution. The minimum sample size, the operating characteristic function values of the new sampling plans as well as the producer’s risk are obtained and the results are illustrated by examples.

Selection of single sampling plans by attributes under the conditions of zero-inflated Poisson distribution

Purpose – The purpose of this paper is to determine single sampling plans (SSPs) by attributes when the number of nonconformities is distributed according to a zero-inflated Poisson (ZIP) distribution. Design/methodology/approach – Manufacturing processes have now-a-days been aligned properly and are monitored well, so that the occurrence of nonconformities would be a rare phenomenon. The information related to number of nonconformities per product will have more number of zeros. Under such circumstances, the appropriate probability distribution of the number of nonconformities is a ZIP distribution. The operating characteristic function of the sampling plan is derived. Findings – Parameters of the sampling plans are obtained for some sets of values of (p 1, α, p 2, β). Numerical examples are given to illustrate the selection of SSPs under ZIP distribution and to study its advantages over Poisson SSP. Originality/value – Results obtained in this paper are original and has been done for the first time in this regard. Parameters of the sampling plans are essential to make decisions either to accept or reject the lots based on the inspection of the samples.