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The purpose of this paper is to develop a group acceptance sampling plan (GASP) for a resubmitted lot when the lifetime of a product follows odds exponential log logistic distribution introduced by Rao and Rao (2014). The parameters of the proposed plan such as minimum group size and acceptance number are determined for a pre-specified consumer’s risk, number of testers and the test termination time. The authors compare the proposed plan with the ordinary GASP, and the results are illustrated with live data example.

The parameters of the proposed plan such as minimum group size and acceptance number are determined for a pre-specified consumer’s risk, number of testers and the test termination time.

The authors determined the group size and acceptance number.

No specific limitations.

This methodology can be applicable in industry to study quality control.

This methodology can be applicable in health study.

The parameters of the proposed plan such as minimum group size and acceptance number are determined for a pre-specified consumer’s risk, number of testers and the test termination time.

This study investigates the repetitive mixed sampling (MRS) plan based on the Cpk index that was proposed by Aslam et al. (2013a). They were the first to study the MRS plan, but they did not pay attention to the fact that submitting to the variable inspection a sample that was first submitted to the attribute inspection, truncates the X observations. In addition, they did not work with an accurate expression to calculate the probabilities of the Cpk statistic.

The authors presented the results based on their original sampling plan through Monte Carlo simulation and defined the theoretical results of their plan when the sample submitted to the variable inspection is no longer the same one submitted to the attribute inspection.

The β risks of the optimum sampling plans presented by Aslam et al. (2013a) are pretty high, exceeding 46%, on average – this same problem was also observed in Saminathan and Mahalingam (2018), Balamurali (2020) and Balamurali et al. (2020), where the β risks of their proposed sampling plans are yet higher.

In terms of originality, the authors can declare the following. It is not a big deal to propose new sampling plans, if one does not know how to obtain their properties. The miscalculations of the sampling plans risks are dangerous; imagine the situation where the acceptance of bad lots exceeds 50% just because the sampling plan was incorrectly designed. Yes, it is a big deal to warn that this type of problem is arising in a growing number of papers. The authors of this study are the pioneers to discover that many studies focusing on the sampling plans need to be urgently revised.

Lifetime data are used in many different applied sciences, like biomedicine, engineering, insurance and finance and others. The purpose of this paper is to develop a new acceptance sampling plans for Rama distribution when the mean lifetime test is truncated at a pre-determined time. The minimum sample sizes required to assert the specified life mean is obtained for a given customer’s risk. The operating characteristic function values of the sampling plans and producer’s risk are calculated.

The results are illustrated using numerical examples and a real data set is considered to illustrate the performance of the suggested acceptance sampling plans and how it can be used for the industry applications.

This paper shows a new acceptance sampling plans based on Rama distribution in the particular case when the mean life time test is truncated.

The results calculated in this paper demonstrate the differences between OC values for different distributions taken into account. In particular, OC values of Rama distribution are found to be less than the proposed distribution counterparts.

The purpose of this paper is to design an optimal reliability acceptance sampling plan (RASP) using the Type-I generalized hybrid censoring scheme (GHCS) for non-repairable products sold under the general rebate warranty. A cost function approach is proposed for products having Weibull distributed lifetimes incorporating relevant costs.

For Weibull distributed product lifetimes, acceptance criterion introduced by Lieberman and Resnikoff (1955) is derived for Type-I GHCS. A cost function is formulated using expected warranty cost and other relevant cost components incorporating the acceptance criterion. The cost function is optimized following a constrained optimization approach to arrive at the optimum RASP. The constraint ensures that the producer's and the consumer's risks are maintained at agreed-upon levels.

Optimal solution using the above approach is obtained for Type-I GHCS. As a special case of Type-I GHCS, the proposed approach is also used to arrive at the optimal design for Type-I hybrid censoring scheme as shown in Chakrabarty et al. (2019). Observations regarding the change in optimal design and computational times between the two censoring schemes are noted. An extensive simulation study is performed to validate the model for finite sample sizes and the results obtained are found to be in strong agreement. In order to analyze the sensitivity of the optimal solution due to misspecification of parameter values and cost components, a well-designed sensitivity analysis is carried out using a real-life failure data set from Lawless (2003). Interesting observations are made regarding the change in optimal cost due to change in parameter values, the impact of warranty cost in optimal design and change in optimal design due to change in lot sizes.

The research presents an approach for designing optimal RASPs using Type-I generalized hybrid censoring. The study formulates optimum life test sampling plans by minimizing the average aggregate costs involved, which makes it valuable in dealing with real-life problems pertaining to product quality management.

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.

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.

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.

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 purposes of this paper are: to view the credit crunch as a decline in certainty and predictability in the world at present, and to examine the challenge this decline presents to leaders, to identify leadership errors that can occur, and to suggest successful leadership strategies relevant to the current challenges.

This paper first explains Taleb's analysis of the effect of unpredictable events and then identifies both common errors and helpful strategies of leadership, giving examples.

It is found that the recent changes in the commercial and financial world, the credit crunch, create considerable leadership challenges. It is also shown that there are things leaders can do to increase or maintain their effectiveness as leaders and there are methodologies they can employ with their organisation to increase the organisation's effectiveness in the face of unfolding uncertainty.

The paper gives clear guidance both on the approach leaders would be wise to avoid and a helpful approach to offering leadership in times of uncertainty.

Taleb's work offers a unique and timely way of understanding how unhelpful behaviour can occur when conditions change suddenly or unpredictably. The paper draws out the implications of his philosophical and intriguing work in a pragmatic, practical, way to make clear its relevance to leadership during the credit crunch.

Discusses the steps taken by Laser Inc. in the development and implementation of a statistical process control (SPC) system for two specific production lines. The SPC programme included a total of 16 steps. Explains each of these steps. Suggests that they are comprehensive in nature and can be used by any organization wanting to implement an SPC system.

The purpose of this paper is to investigate a moderated mediation model of innovative work behaviour enhancement. Perceived firm (organizational and market) performance was assumed to moderate the relationships between leader-member exchange (LMX) and organizational citizenship behaviour (OCB), on the one hand, and employability, on the other hand. In a preciously validated human resources management (HRM) model, employability appeared to be a full mediator in the relationship between LMX and OCB, and innovative work behaviour, being the outcome measure.

Data were collected from a sample of 487 pairs of employees and their immediate supervisors working in 151 small and medium-sized enterprises (SMEs). Structural equation modeling (SEM) was used to confirm the factor structure of the baseline model variables, including LMX, OCB, employability, and innovative work behaviour. The moderating effect of firm performance was tested using multi-group SEM.

Results indicated that firm performance had a substantial influence on the baseline model's relationships. More specifically, firm performance appeared to moderate partially a mediation model wherein LMX was assumed to be associated with innovative work behaviour, through employability, being the mediator. Moreover, firm performance also appeared to moderate conclusively a model with employability as a mediator in the relationship between OCB and innovative work behaviour.

To the best of our knowledge, this is the very first study that investigates a mediation model of innovative work behaviour enhancement moderated by firm performance. It appears that high- vs low-performance firms present very different organizational environments for an employee to work in. Obviously, these situational factors affect workers’ employability. This study adds particular knowledge to the scholarly literature in this field since not much is known about the science and practice of HRM within SMEs.