Entropy-based goodness-of-fit tests for the Pareto I distribution

In this article, having observed the generalized order statistics in a sample, we construct a test for the hypothesis that the underlying distribution is the Pareto I distribution. The Shannon entropy of generalized order statistics is used to test the null hypothesis.     

天然气操作成本影响因素分析方法研究

以HTB气田为例,首先采用帕累托原理和灰关联分析,找出气田操作成本中的主要影响因素和各分项费用与操作成本之间的关联度,再采用指数分析法精确地描述其变动的影响因素,从而全面、准确分析天然气操作成本变动情况,为天然气成本控制和提高气田的经济效益提供科学依据。     

A family of repeated measurements models

A general family of multivariate distributions for repeated measures can be obtained by applying the Laplace transform of a gamma distribution to the integrated intensity function of any continuous distribution on the positive real line. Both clustering and serial dependence can be handled. The response variable may be counts, durations between events, or any continuous positive-valued measurements.     

Dual Objective Segmentation to Improve Targetability: An Evolutionary Algorithm Approach**

Cluster‐based segmentation usually involves two sets of variables: (i) the needs‐based variables (referred to as the bases variables), which are used in developing the original segments to identify the value, and (ii) the classification or background variables, which are used to profile or target the customers. The managers’ goal is to utilize these two sets of variables in the most efficient manner. Pragmatic managerial interests recognize the underlying need to start shifting from methodologies that obtain highly precise value‐based segments but may be of limited practical use as they provide less targetable segments. Consequently, the imperative is to shift toward newer segmentation approaches that provide greater focus on targetable segments while maintaining homogeneity. This requires dual objective segmentation, which is a combinatorially difficult problem. Hence, we propose and examine a new evolutionary methodology based on genetic algorithms to address this problem. We show, based on a large‐scale Monte Carlo simulation and a case study, that the proposed approach consistently outperforms the existing methods for a wide variety of problem instances. We are able to obtain statistically significant and managerially important improvements in targetability with little diminution in the identifiability of value‐based segments. Moreover, the proposed methodology provides a set of good solutions, unlike existing methodologies that provide a single solution. We also show how these good solutions can be used to plot an efficient Pareto frontier. Finally, we present useful insights that would help managers in implementing the proposed solution approach effectively.     

Optimal designs for the power logistic model

We investigate non-sequential designs for estimating model parameters in a power logistic model when the power is assumed to be approximately known and only the ranges for the other two parameters are available. The sensitivity of these designs to nominal values of all the three parameters are studied and our proposed optimal designs are shown to be reasonably robust under moderate deviation from the assumed model. An application to a toxicity experiment involving adult beetles is discussed, including the benefits of using an optimal design.     

Bayesian estimation and prediction based on generalized Type-II hybrid censored sample

ABSTRACT

In this paper, we consider a general form for the underlying distribution and a general conjugate prior, and develop a general procedure for deriving the maximum likelihood and Bayesian estimators based on an observed generalized Type-II hybrid censored sample. The problems of predicting the future order statistics from the same sample and that from a future sample are also discussed from a Bayesian viewpoint. For the illustration of the developed results, the exponential and Pareto distributions are used as examples. Finally, two numerical examples are presented for illustrating all the inferential procedures developed here.     

对效率市场体系的理论思考

效率市场有着更丰富的内容,而不仅局限于股票效率市场。按研究的层次分,效率市场可分为微观效率市场、中观效率市场和宏观效率市场。微观效率市场是帕累托效率市场,是效率市场体系的基础,但微观市场存在空间失灵和经济、社会失灵。作为对微观市场失灵的纠正,中观效率市场表现为城乡一体化市场,宏观效率市场表现为宏观经济目标实现的全国统一大市场。三个层次的效率市场相互作用、相互推动,构成了一个完整的动态市场运行体系。     

Design of an attribute np control chart for process monitoring based on repetitive group sampling under truncated life tests

In this paper, an attribute control chart under repetitive group sampling is designed for monitoring the production process where the lifetime of the product is considered as quality of the product. We assume that the lifetime follows the Pareto distribution of second kind with known shape parameter. The performance of the proposed chart is evaluated by average run length. The control limits coefficients as well as the repetitive group sampling parameter such as sample size are determined such that the in-control average run length is as close as to the specified average run length. Out-of-control average run length is also reported for different shift constants with corresponding optimal parameters. In addition, performance of proposed control chart is compared with the performance of existing chart. An economical designing of proposed control chart is also discussed.     

Firm size distributions and stochastic growth models: a comparison between ICT and Mechanical Italian Companies

In this paper we analyze the relationship between the distribution of firm size and stochastic processes of growth. Three main models have been suggested by Gibrat (1931), Kalecki (1945) and Champernowne (1973). The first two lead to lognormal distribution and the last to Pareto distribution. We fitted lognormal and Pareto distribution to two Italian sectors: ICT and mechanical. For ICT we found that lognormal distribution must be rejected and Pareto fits reasonably well to the last 30% of largest companies. For mechanical sector we can not reject lognormal distribution. Furthermore, we perform some experiments to corroborate the theoretical models. By means of transition matrices we found that ICT shows features very close to Gibrats and Champernownes models, while Kaleckis model strongly fits to mechanical.JEL Classification: L00, L25, D21Correspondence to: Luigi GrossiThis research was partially supported by grants from Ministero dellIstruzione, dellUniversitá e della Ricerca (MIUR). Despite being the results of a joint work, Sects. 1, 4, 8 and 10 should be attributed to Ganugi, Sects. 3, 6, and 7 to Grossi and Sects. 2, 5, and 9 to Crosato.     

对"帕累托最优"的伦理诘问

经济学与伦理学有着深刻的内在关联,但是在经济学发展的历程中,经济学抛弃了它的伦理学渊源,逐渐脱离和淡化伦理学的影响,以"自利最大化"为理论前提、以"社会效用"为标准的"帕累托最优"就是在这种背景下产生的.现代经济学家阿玛蒂亚·森对拒绝伦理考虑的"帕累托最优"提出质疑和挑战,并努力在经济学的研究中重新引入价值判断和道德哲学的智慧,在这个基础上提出新的衡量经济发展的标准.