Issue Information

In 2017, the number of applications for care orders in England and Wales was the highest ever recorded at 14,207. This is a significant factor, contributing to the rise in the number of children who are looked after, which is at the highest level since 1985. The authors reflect on the recently published Care Crisis Review 2018, a sector‐led review, which examines the reasons for the rise in care proceedings and the number of children in care. The review sought to identify changes to policy and practice within local authorities and the family justice system, in an attempt to divert cases away from the family courts and to reduce the number of children in care, where it is safe to do so. Whilst the legislative framework is largely effective and the system generally works well, there is insufficient funding and resources to meet the needs of children and their families when they seek help, regardless of whether this is at an early stage or when they are in crisis and most in need of care and protection.     

We Don’t Belong Here: Adolescents of North Korean Refugee Families and Their Suicidal Behaviors

Despite the increasing number of studies that examine the link between immigration and suicide in Korean youths, most have focused on self-harming behaviours among adolescents in multicultural families, while much less attention has been directed towards those in North Korean (NK) refugee families. This paper addresses this gap by comparing three determinants of suicidal behaviours across three groups of Korean adolescents. Data are drawn from the KYRBS, a nationally representative sample of students in middle and high schools, and the results indicate that NK youths were 87.2 per cent more likely to have suicidal ideation than their South Korean peers, that they are 3.7 times more likely to experience suicidal plans and 4.1 times more likely to attempt suicide. These results clearly suggest that immigrant youths, including NK refugees, are confronting significant difficulties with assimilation, and those disadvantages lead to a higher propensity of self-threatening behaviours.     

TOTAL QUALITY MANAGEMENT: A LITERATURE REVIEW AND AN AGENDA FOR FUTURE RESEARCH

Total quality management (TQM) is a revolutionary approach to effective management. The research in TQM has emerged from practical needs of organizations embracing this philosophy, and the literature is mostly conceptual and practitioner-oriented. There is a lack of sound theoretical framework classifying past efforts and guiding future research. To fill the void, a study of the published TQM literature is undertaken. A review, classification, and analysis of the research in TQM spanning the last two decades is presented. A total of 226 TQM-related articles are identified from 44 refereed management journals published from 1970 to 1993. These articles are then classified and analyzed using the following two-dimensional scheme: (1) article orientation (conceptual, case study, empirical, analytical, simulation, and overview) and (2) article focus using the Malcolm Baldrige National Quality Award criteria. The analysis of the literature presents pertinent developments in each of the seven criteria. In addition, it provides future research directions as well as a ready reference of the TQM literature. The suggestions for research should guide future developments in the TQM field and help transform it into a formal discipline.     

Bringing Japanese Continuous Improvement Approaches to U.S. Manufacturing: The Roles of Process Orientation and Communications*

Continuous improvement (CI) has played a key role in Japan's quality management. U.S. companies have begun to adopt CI in recent years. This paper studies the implementation of CI in seven U.S. manufacturing companies. We view values as the core concept of culture that impacts CI effectiveness. Using both qualitative and quantitative data with a sample of seven companies, we observe empirically a relationship between process-oriented values and CI effectiveness. We also find that communications involving workers is strongly associated with CI effectiveness. Finally, we find an association between process orientation and communication frequency, and argue that communications act as an intervening variable between process orientation and effectiveness.     

Noninformative priors for the between-group variance in the unbalanced one-way random effects model with heterogeneous error variances

For the unbalanced one-way random effects model with heterogeneous error variances, we propose the non-informative priors for the between-group variance and develop the first- and second-order matching priors. It turns out that the second-order matching priors do not exist and the reference prior and Jeffreys prior do not satisfy a first-order matching criterion. We also show that the first-order matching prior meets the frequentist target coverage probabilities much better than the Jeffreys prior and reference prior through simulation study, and the Bayesian credible intervals based on the matching prior and reference prior give shorter intervals than the existing confidence intervals by examples.     

Theoretical results on the discrete Weibull distribution of Nakagawa and Osaki

In this paper, we discuss some theoretical results and properties of the discrete Weibull distribution, which was introduced by Nakagawa and Osaki [The discrete Weibull distribution. IEEE Trans Reliab. 1975;24:300–301]. We study the monotonicity of the probability mass, survival and hazard functions. Moreover, reliability, moments, p-quantiles, entropies and order statistics are also studied. We consider likelihood-based methods to estimate the model parameters based on complete and censored samples, and to derive confidence intervals. We also consider two additional methods to estimate the model parameters. The uniqueness of the maximum likelihood estimate of one of the parameters that index the discrete Weibull model is discussed. Numerical evaluation of the considered model is performed by Monte Carlo simulations. For illustrative purposes, two real data sets are analyzed.     

Small‐sphere distributions for directional data with application to medical imaging

We propose novel parametric concentric multi‐unimodal small‐subsphere families of densities for p ? 1 ≥ 2‐dimensional spherical data. Their parameters describe a common axis for K small hypersubspheres, an array of K directional modes, one mode for each subsphere, and K pairs of concentrations parameters, each pair governing horizontal (within the subsphere) and vertical (orthogonal to the subsphere) concentrations. We introduce two kinds of distributions. In its one‐subsphere version, the first kind coincides with a special case of the Fisher–Bingham distribution, and the second kind is a novel adaption that models independent horizontal and vertical variations. In its multisubsphere version, the second kind allows for a correlation of horizontal variation over different subspheres. In medical imaging, the situation of p ? 1 = 2 occurs precisely in modeling the variation of a skeletally represented organ shape due to rotation, twisting, and bending. For both kinds, we provide new computationally feasible algorithms for simulation and estimation and propose several tests. To the best knowledge of the authors, our proposed models are the first to treat the variation of directional data along several concentric small hypersubspheres, concentrated near modes on each subsphere, let alone horizontal dependence. Using several simulations, we show that our methods are more powerful than a recent nonparametric method and ad hoc methods. Using data from medical imaging, we demonstrate the advantage of our method and infer on the dominating axis of rotation of the human knee joint at different walking phases.     

On Bartlett correction of empirical likelihood for regularly spaced spatial data

Bartlett correction constitutes one of the attractive features of empirical likelihood because it enables the construction of confidence regions for parameters with improved coverage probabilities. We study the Bartlett correction of spatial frequency domain empirical likelihood (SFDEL) based on general spectral estimating functions for regularly spaced spatial data. This general formulation can be applied to testing and estimation problems in spatial analysis, for example testing covariance isotropy, testing covariance separability as well as estimating the parameters of spatial covariance models. We show that the SFDEL is Bartlett correctable. In particular, the improvement in coverage accuracies of the Bartlett‐corrected confidence regions depends on the underlying spatial structures. The Canadian Journal of Statistics 47: 455–472; 2019 © 2019 Statistical Society of Canada     

Communication in Statistics-Theory and methods improved GQL estimation method for the generalised BINMA(1) model

In a recent research, the quasi-likelihood estimation methodology was developed to estimate the regression effects in the Generalized BINMA(1) (GBINMA(1)) process. The method provides consistent parameter estimates but, in the intermediate computations, moment estimating equations were used to estimate the serial- and cross-correlation parameters. This procedure may not result optimal parameter estimates, in particular, for the regression effects. This paper provides an alternative simpler GBINMA(1) process based on multivariate thinning properties where the main effects are estimated via a robust generalized quasi-likelihood (GQL) estimation approach. The two techniques are compared through some simulation experiments. A real-life data application is studied.     

Business Collaboration within the Nazi War Machine: Corporations and the State in the Austrian Semiperiphery

The military strength of German National Socialism was based on the collaboration of large corporations with the Nazi state. Business provided capital, loans, taxes, managerial expertise and production for war industries. I elaborate four ideal‐typical modes of business collaboration. Each mode is illustrated by a case study of a German corporation that acquires an Austrian firm: Krupp (traditional mode); the Reichswerke state conglomerate (coercive); Deutsche Bank (managerial nationalist); and IG Farben (competitive investment mode). The first and the last modes occurred when the state was highly dependent on large businesses for the economic requisites of war. The acquired firms in the Austrian semiperiphery contributed to Nazi war mobilization, as they exploited labor and resources from the peripheral regions of southeastern Europe. Patterns of the state's resource dependency on business led to bargaining interactions between state and business, over time shaping the mix between state and private ownership of war industry.