Relative efficiency of a parameter for a M/G/1 queueing system based on reduced and full likelihood functions

The present paper derives the relative efficiency of a parameter for the M/G/1 queueing system based on reduced and full likelihood functions. Monte Carlo simulations were carried out to study the finite sample properties for estimating the parameters of a M/G/1 queueing system. The simulation runs were conducted using various traftic intensities with increaseing sample sizes. The simulation results indicate that the loss in efficiency is quite small due to the use of a reduced likelihood function approach for estimating the parameter instead of the full likelihood, even for a moderate sample size of 50     

A Fairly Accurate Approximation to the Area Under Normal Curve

In this article, we present a new approximation to the cumulative distribution function of standard normal distribution. The approximation is fairly accurate with minimum accuracy of seven decimal digits. To the best of our knowledge, this formula outperforms other such approximations available in literature.     

The propagation of lean thinking in SMEs

Abstract

Small and Medium-sized Enterprises (SMEs) play a pivotal role in economic growth, industrial output, and employment creation. However, SMEs are often ignored by researchers as far as the adoption of lean is concerned in comparison to Large Enterprises (LEs). Therefore, the literature regarding lean implementation in SMEs is not conspicuous, and many SMEs have only a limited understanding and awareness of lean. This paper offers a comprehensive literature review with a focus on the implementation of lean in SMEs and explores the applicability of lean thinking in such environments. An attempt is made to provide an analysis of lean practices that have been applied in SMEs and critical success factors for lean transformation in SMEs. It also contributes to the field of lean implementation research by proposing a framework for lean in SMEs and identifies the scope of future research.     

Detecting outliers: power and some other considerations

The general problem of outlier detection and five recursive outlier detection procedures considered in the study are defined. The methods to compute powers, probabilities of detecting ≥1 outliers, and >1 observations including at least one inlier as outliers are computed and results are discussed. Results show that no procedure is most powerful when the actual number of outlier present in the sample is exactly, under-, and overestimated. The probabilities of inliers being detected as outliers are also substantial particularly when outliers occur only on one side of the sample     

Stochastic properties of conditionally independent mixture models

This paper deals with aging properties and stochastic comparisons of multivariate mixture models, having conditionally independent marginal distributions.     

Estimation of common location parameter of several heterogeneous exponential populations based on generalized order statistics

In this article, several independent populations following exponential distribution with common location parameter and unknown and unequal scale parameters are considered. From these populations, several independent samples of generalized order statistics (gos) are drawn. Under the setup of gos, the problem of estimation of common location parameter is discussed and various estimators of common location parameter are derived. The authors obtained maximum likelihood estimator (MLE), modified MLE and uniformly minimum variance unbiased estimator of common location parameter. Furthermore, under scaled-squared error loss function, a general inadmissibility result of invariant estimator is proposed. The derived results are further reduced for upper record values which is a special case of gos. Finally, simulation study and real life example are reported to show the performances of various competing estimators in terms of percentage risk improvement.     

The Relationship of Problem Gambling to Criminal Behavior in a Sample of Canadian Male Federal Offenders

This article examines the prevalence of moderate and severe problem gambling in a sample of 254 incarcerated Canadian male federal offenders (completion rate of 39.0%). The prevalence of disordered gambling was measured using the PGSI, DSM-IV-TR, and SOGS that yielded estimates of 9.4%, 6.3%, and 13.0%, respectively. Severe problem gamblers were significantly more likely to have committed income producing offences, but were neither more nor less likely than other offenders to have committed violent offences. The majority of severe problem gamblers (65.2%) and a fifth of the moderate problem gamblers (20.0%) reported that their criminal activity was a result of their gambling (e.g., to pay off debts). Based on these findings there appears to be a need to offer problem gambling treatment services to offenders in order to help them break the cycle of gambling, debt and crime.     

Single process plan scheduling with genetic algorithms

AIn this paper, a genetic algorithm model for scheduling manufacturing resources is developed for the case when there is only one process plan available per job, hence there is no routeing flexibility. The scheduling objectives considered are minimizing the makespan and mean flow time. Genetic algorithms design issues are discussed and the working of the employed genetic operators is explained in detail. Parameters for the genetic algorithms used for single process plan scheduling SPPS problems are set through extensive experimentation. Finally, the genetic algorithms approach is compared with several other approaches in terms of optimality of solution and computAuthors: ing time. It was observed that in most cases the genetic algorithms approach performed better than other approaches both in terms of finding an optimal or near optimal solution as well as computing time.     

State of international public relations research: Narrowing the knowledge gap about the practice across borders

This study examined the state of international public relations research to identify prominent trends, themes, and theoretical paradigms in the field. A content analysis of 200 articles from 12 peer reviewed journals shows that international public relations scholarship has increased steadily in the last four years. Likewise, the areas being studied by academics in the field have also diversified. The findings point to areas and regions that remain understudied and should be explored to continue building knowledge in the field in general, and more specifically, in theory development.