Bias‐Corrected Estimation in Continuous Sampling Plans

Continuous sampling plans (CSPs) are algorithms used for monitoring and maintaining the quality of a production line. Although considerable work has been done on the development of CSPs, to our knowledge, there has been no corresponding effort in developing estimators with good statistical properties for data arising from a CSP inspection process. For example, information about the failure rate of the process will affect the management of the process, both in terms of selecting appropriate CSP parameters to keep the failure rate after inspection at a suitable level, and in terms of policy, for example, whether the process should be completely inspected, or shut down. The motivation for this exercise was developing sampling protocols for Australia's Department of Agriculture and Water Resources for monitoring the biosecurity compliance of incoming goods at international borders. In this study, we show that maximum likelihood estimation of the failure rate under a sampling scheme can be biased depending on when estimation is performed, and we provide explicit expressions for the main contribution of the bias under various CSPs. We then construct bias‐corrected estimators and confidence intervals, and evaluate their performance in a numerical study.     

Italian Urban Plans: Diversified Approaches and Methods for Assessing Their Quality

This article poses the difficult task of providing a brief overview of Italian urban planning, difficult to understand for foreign observers because each Region has different legislation and urban planning tools. The paper describes an original methodology that evaluates the quality of the approach differentiated as (1) ‘of the plan’ (reformist, participative, from the territory); (2) ‘in the plan’ (integrated strategic, sustainable); (3) ‘with the plan’ (conformative, methodological, recompositional, systemic-infrastructural); and (4) ‘beyond the plan’ (beyond governance methodologies). The paper also compares aspects of quality present in plans for large, medium and small Italian cities. The conclusions review factors of excellence that may be used in other international scenarios.     

Restricted optimal progressive censoring

Unlike traditional Type I and II censoring, progressive censoring allows for removal of surviving units throughout the life test. This feature has several benefits and in the literature, much work has been done on inference based on progressively censored samples and identifying optimal progressive censoring schemes. In this paper, we introduce restricted progressive censoring and within this class, the problem of identifying optimal schemes under different minimum variance criteria. We explore these plans geometrically as well as provide some useful properties. In particular, we look at the vertices of the set of admissible plans and their role in approximating optimal plans. We also provide computational results for illustrative purposes.     

Matching Performance of Continuous Sampling Plans with Single Sampling Plans

Single sampling plans are widely used for appraising incoming product quality. However, for situations where a continuous product flow exists, lot-by-lot demarcations may not exist, and it may be necessary to use alternate procedures, such as CSP-1, for continuous processes. In this case, one would like to be able to understand how average performance of the continuous sampling procedures compares to the more commonly used single sampling plans.

In this study, a model is devised which can be used to relate plan performance between single sample lot acceptance procedures and Dodge's(1943) CSP-1 continuous sampling plan. It is shown that it is generally not possible to match up performance based upon operating characteristic curve expressions for the two plans. Instead, the plans are matched by equating expressions for π(p), the long run proportion of product which is accepted, under both procedures. This is shown to be equivalent to matching up properties on an average outgoing quality basis. The methodology may be extended for any derivative plan under MIL-STD-1235B (1982), the military standard for continuous acceptance sampling.     

Optimal Designs for 2 k Choice Experiments

Abstract

In this article we establish the choice sets in the D-optimal design for a choice experiment for testing main effects and for testing main effects and two-factor interactions, when there are k attributes, each with two levels, for choice set size m. We also give a method to construct optimal and near-optimal designs with small numbers of choice sets.     

姚锡光与晚清边疆治理

姚锡光是清末民初一位有着多重身份的历史人物,从外交随员、督抚幕僚、地方官员,到考察教育、传播西学的教育家,以及锐意革新、兴办海军的军事家,关心边疆民族问题的中央政府官员,其一生经历丰富,著述颇丰。他的代表作有《东方兵事纪略》、《东瀛学校举概》、《吏皖存牍》、《筹藏刍议》、《筹蒙刍议》、《筹海军别录》、《姚锡光日记》、《姚锡光文稿》等,这些著作对军事、地方事务、民族问题都有不俗的见解,具有较高的参考价值。     

统筹城乡经济社会发展的枢纽选择

统筹城乡经济社会发展,要选择和强化四个枢纽:一是大力发展农产品加工业,强化产业枢纽;二是加快城镇化步伐,完善空间枢纽;三是建立健全农业技术信息体系,完善技术信息枢纽;四是调整国民收入分配格局,形成城市反哺农村的利益枢纽.     

Use of Risk Assessment Methods in the Certification of Decontaminated Buildings

Accidental events such as fires, explosions, and leaks often result in large-scale contaminations of buildings with toxic chemicals. After decontamination, the certification for original use requires testing for residual contamination. The two basic kinds of sampling plans in use up to recently both fall short of the required performance. Their deficiencies are analyzed in terms of the scientific questions implicit in both the sampling plan and the subsequent statistical evaluation. A sampling strategy of a new kind is proposed and discussed in the same context. It is motivated by concern for the long-term safety of the building's occupants and is, therefore, based on factors important in risk assessment. Three different sampling plans are derived in the framework of this methodology, two of which have already been used in actual certification proceedings.     

论以人为本,全面、协调、可持续的发展观

以人为本,全面、协调、可持续的发展观,是对马克思主义发展理论的继承、丰富和发展,充满了与时俱进的创新精神,标志着中国发展战略的新的重大调整。这一新的科学的发展观不仅具有丰富的内涵,而且是综合的、立体的、多维的辩证统一整体。要真正做到经济社会的全面、协调、可持续发展,进而促进人的全面发展,首要的是按照这一发展观的根本要求,从我国发展的实际出发,统筹兼顾,正确认识和处理好影响当前及今后经济社会发展的一些重大关系。     

Balanced e-optimal designs of resolution III for the 2×3 series

We consider the problem of constructing designs which are E-optimal in the class of all balanced resolution III designs for the 2^m×3ⁿ series. The inverse of the information matrix for general resolution III balanced 2^m×3ⁿ designs is obtained. Optimal designs are constructed for the cases (m,n)=(3, 1), (4, 1), (2, 2) and (3, 2) for various numbers of runs in the practical range.