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21.
Greening the supply chain is increasingly a concern for many business enterprises and a challenge for logistics management in the 21st century. Of particular concern is how to arouse organizational environmental awareness and put environmental activities into practice in the logistics activities of their supply chains. This paper investigates the correlation of two major factors, organizational learning and management support, with the extent of adoption of green supply chain management (GSCM) practices in Chinese manufacturing firms, where their inbound and outbound logistics activities are potential polluters to the environment. Organizational and operational learning was derived from the firm's experience with programs such as total quality management and environmental management systems. Management support included support for GSCM ideas and practices from top and middle-level management and cooperation across organizational functions. We find significant positive relationships between organizational learning mechanisms, organizational support and the adoption of GSCM practices, after controlling for a number of other influences including regulations, marketing, supplier, cost pressures, industry levels of the relevant practice and organizational size. Implications of our findings on logistics management are discussed. 相似文献
22.
Gauss M. Cordeiro Thiago G. Ramires Edwin M. M. Ortega 《Journal of Statistical Computation and Simulation》2018,88(3):432-456
We introduce a new class of distributions called the Burr XII system of densities with two extra positive parameters. We provide a comprehensive treatment of some of its mathematical properties. We estimate the model parameters by maximum likelihood. We assess the performance of the maximum likelihood estimators in terms of biases and mean squared errors by means of a simulation study. We also introduce a new family of regression models based on this system of densities. The usefulness of the proposed models is illustrated by means of three real data sets. 相似文献
23.
Thiago G. Ramires Niel Hens Gauss M. Cordeiro Gilberto A. Paula 《Journal of applied statistics》2018,45(7):1303-1324
In this paper, we propose a new semiparametric heteroscedastic regression model allowing for positive and negative skewness and bimodal shapes using the B-spline basis for nonlinear effects. The proposed distribution is based on the generalized additive models for location, scale and shape framework in order to model any or all parameters of the distribution using parametric linear and/or nonparametric smooth functions of explanatory variables. We motivate the new model by means of Monte Carlo simulations, thus ignoring the skewness and bimodality of the random errors in semiparametric regression models, which may introduce biases on the parameter estimates and/or on the estimation of the associated variability measures. An iterative estimation process and some diagnostic methods are investigated. Applications to two real data sets are presented and the method is compared to the usual regression methods. 相似文献
24.
A new general class of exponentiated sinh Cauchy regression models for location, scale, and shape parameters is introduced and studied. It may be applied to censored data and used more effectively in survival analysis when compared with the usual models. For censored data, we employ a frequentist analysis for the parameters of the proposed model. Further, for different parameter settings, sample sizes, and censoring percentages, various simulations are performed. The extended regression model is very useful for the analysis of real data and could give more adequate fits than other special regression models. 相似文献
25.
Edwin M.M. Ortega Gauss M. Cordeiro Michael W. Kattan 《Journal of applied statistics》2012,39(6):1191-1210
In this article, for the first time, we propose the negative binomial–beta Weibull (BW) regression model for studying the recurrence of prostate cancer and to predict the cure fraction for patients with clinically localized prostate cancer treated by open radical prostatectomy. The cure model considers that a fraction of the survivors are cured of the disease. The survival function for the population of patients can be modeled by a cure parametric model using the BW distribution. We derive an explicit expansion for the moments of the recurrence time distribution for the uncured individuals. The proposed distribution can be used to model survival data when the hazard rate function is increasing, decreasing, unimodal and bathtub shaped. Another advantage is that the proposed model includes as special sub-models some of the well-known cure rate models discussed in the literature. We derive the appropriate matrices for assessing local influence on the parameter estimates under different perturbation schemes. We analyze a real data set for localized prostate cancer patients after open radical prostatectomy. 相似文献
26.
Gauss M. Cordeiro 《统计学通讯:理论与方法》2013,42(1):197-207
ABSTRACT In this article we derive finite-sample corrections in matrix notation for likelihood ratio and score statistics in extreme-value linear regression models. We consider three corrected score tests that perform better than the usual score test. We also derive general formulae for second-order biases of maximum likelihood estimates of the linear parameters. Some simulations are performed to compare the likelihood ratio and score statistics with their modified versions and to illustrate the bias correction. 相似文献
27.
M. H. Tahir Gauss M. Cordeiro Ayman Alzaatreh M. Mansoor M. Zubair 《统计学通讯:模拟与计算》2016,45(10):3548-3567
Many distributions have been used as lifetime models. In this article, we propose a new three-parameter Weibull–Pareto distribution, which can produce the most important hazard rate shapes, namely, constant, increasing, decreasing, bathtub, and upsidedown bathtub. Various structural properties of the new distribution are derived including explicit expressions for the moments and incomplete moments, Bonferroni and Lorenz curves, mean deviations, mean residual life, mean waiting time, and generating and quantile functions. The Rényi and q entropies are also derived. We obtain the density function of the order statistics and their moments. The model parameters are estimated by maximum likelihood and the observed information matrix is determined. The usefulness of the new model is illustrated by means of two real datasets on Wheaton river flood and bladder cancer. In the two applications, the new model provides better fits than the Kumaraswamy–Pareto, beta-exponentiated Pareto, beta-Pareto, exponentiated Pareto, and Pareto models. 相似文献
28.
This paper provides Bartlett corrections to improve likelihood ratio tests for heteroskedastic normal linear models when the error covariance matrix is nonscaiar and depends on a set of unknown parameters. The Bartlett corrections are simple enough to be used algebraically to obtain several closed-form expressions in special cases. The corrections have also advantages for numerical purposes because they involve only simple operations on matrices and vectors. 相似文献
29.
Audrey H. M. A. Cysneiros Katya S. P. Rodrigues Gauss M. Cordeiro Silvia L. P. Ferrari 《Statistical Papers》2010,51(2):273-284
We present simple matrix formulae for corrected score statistics in symmetric nonlinear regression models. The corrected score
statistics follow more closely a χ
2 distribution than the classical score statistic. Our simulation results indicate that the corrected score tests display smaller
size distortions than the original score test. We also compare the sizes and the powers of the corrected score tests with
bootstrap-based score tests. 相似文献
30.
This article reports the experience of the design team of the Laboratory The Imaginary in the process of developing an electric potter's lathe which respects the biomechanics of the body, helps to development the task, maintains the archetype of traditional equipment, and improves the mechanical efficiency of the power transmission system. The design method used was based on the axes of research, analysis, development and monitoring, and focused on the product and with partners: the artisans and engineering and production teams. The main results point to ergonomic improvements in the biomechanical and dimensional aspects, and a decrease in the risk of accidents and occupational diseases. The experience of this case also highlights the gains arising from the relationship between design, engineering and users (artisans) in developing products with a design that can be easily replicated for other communities of potters in the state. This and other actions are part of the outlook of the Laboratory the Imaginary which in partnership with local authorities, wishes to see the craft activities continue and to give value to the culture of the city. 相似文献