SPC as a tool for creating a successful business measurement framework

Many companies are trying to get to the bottom of what their main objectives are and what their business should be doing. The new Six Sigma approach concentrates on clarifying business strategy and making sure that everything relates to company objectives. It is vital to clarify each part of the business in such a way that everyone can understand the causes of variation that can lead to improvements in processes and performance. This paper describes a situation where the full implementation of SPC methodology has made possible a visual and widely appreciated summary of the performance of one important aspect of the business. The major part of the work was identifying the core objectives and deciding how to encapsulate each of them in one or more suitable measurements. The next step was to review the practicalities of obtaining the measurements and their reliability and representativeness. Finally, the measurements were presented in chart form and the more traditional steps of SPC analysis were commenced. Data from fast changing business environments are prone to many different problems, such as the short previous span of typical data, strange distributions and other uncertainties. Issues surrounding these and the eventual extraction of a meaningful set of information will be discussed in the paper. The measurement framework has proved very useful and, from an initial circulation of a handful of people, it now forms an important part of an information process that provides responsible managers with valuable control information. The measurement framework is kept fresh and vital by constant review and modifications. Improved electronic data collection and dissemination of the report has proved very important.     

SPC—making it work for the gas transportation business

Transco is the main provider of gas transportation to domestic and commercial customers in mainland Britain. Gas arrives in Britain at a steady rate but is consumed with a distinct diurnal pattern. The safe and timely movement of gas from arrival at the beach in various places in Britain to delivery at burners is the main driver for System Operations. The movement of gas is meticulously controlled and monitored resulting in a mass of information on pressure, flow and temperature. Gas is stored temporarily in various storage vessels and is moved around the pipes and in and out of storage as demand dictates. Demand is mostly dictated by the weather and is therefore subject to much variation. Transco and its predecessors have been transporting gas for over 50 years and are very successful as judged by their excellent safety record and the continual delivery of gas. Nevertheless, the company wished to improve itself and make further use of the many measurements collected. SPC is ideal for improving communication and understanding through increased visibility of data. All companies have special issues to face when they implement SPC, and this paper describes the way these were dealt with in System Operations and the lessons learnt along the way. The first part describes how performance measures were chosen for investigation. It includes a novel use of correlation between output and day-to-day conditions, which was successfully turned into a measure to check the uncheckable. The second part is about the issues involved with early application of SPC when features of the system are still unexplained. SPC has helped enhance understanding of the complex transportation process, encouraged team work, improved performance and provided an objective means of decision making.     

SPC—making it work for the gas transportation business

Transco is the main provider of gas transportation to domestic and commercial customers in mainland Britain. Gas arrives in Britain at a steady rate but is consumed with a distinct diurnal pattern. The safe and timely movement of gas from arrival at the beach in various places in Britain to delivery at burners is the main driver for System Operations. The movement of gas is meticulously controlled and monitored resulting in a mass of information on pressure, flow and temperature. Gas is stored temporarily in various storage vessels and is moved around the pipes and in and out of storage as demand dictates. Demand is mostly dictated by the weather and is therefore subject to much variation. Transco and its predecessors have been transporting gas for over 50 years and are very successful as judged by their excellent safety record and the continual delivery of gas. Nevertheless, the company wished to improve itself and make further use of the many measurements collected. SPC is ideal for improving communication and understanding through increased visibility of data. All companies have special issues to face when they implement SPC, and this paper describes the way these were dealt with in System Operations and the lessons learnt along the way. The first part describes how performance measures were chosen for investigation. It includes a novel use of correlation between output and day-to-day conditions, which was successfully turned into a measure to check the uncheckable. The second part is about the issues involved with early application of SPC when features of the system are still unexplained. SPC has helped enhance understanding of the complex transportation process, encouraged team work, improved performance and provided an objective means of decision making.     

Concurrent Design for Process Quality,Statistical Tolerance,and SPC

The rapid response to the requirements of customers and markets promotes the concurrent engineering (CE) technique in product and process design. The decision making for process quality target, SPC method, sampling plan, and control chart parameter design can be done at the stage of process quality plan based on historical data and process knowledge database. Therefore, it is a reasonable trend to introduce the concepts and achievements on process quality evaluation and process capability analysis, CE, and SPC techniques into process plan and tolerance design. A new systematic method for concurrent design of process quality, statistical tolerance (ST), and control chart is presented based on a NSFC research program. A set of standardized process quality indices (PQIs) for variables is introduced for meeting the measurement and evaluation to process yield, process centering, and quality loss. This index system that has relatively strong compatibility and adaptability is based on raisonne grading by using the series of preferred numbers and arithmetical progression. The expected process quality based on this system can be assured by a standardized interface between PQIs and SPC, that is, quality-oriented statistical tolerance zone. A quality-oriented ST and SPC approach that quantitatively specifies what a desired process is and how to assure it will realize the optimal control for a process toward a predetermined quality target.     

电子商务客户网络购物行为挖掘

电子商务已经成为越来越多的消费者购物的一个重要途径，分析网络购物客户的个人特征及其购物行为，对商业的成功有着至关重要的作用。然而电子商务还是一个崭新的商业领域，很多的业界人士仍忙于技术方面的考虑，却很少分析客户的网络购买行为。而使用真实网络购物KDD Cup 2000数据，分析Gazelle．com公司客户的个人特征和网络购物行为，并应用数据挖掘的购物篮模型对各商品之间的关联性进行分析，才能更确切地预测模型预测客户的忠诚度。     

大数据应用的质量控制

数据作为重要的数据资源存在，不论是其内在蕴含的信息价值还是其已经成为人类社会所需数据有机组成的客观事实，都迫使我们去不断加强对大数据的应用。然而，由于大数据作为信息技术应用的副产品，其复杂性、不确定性和涌现性决定了我们应用大数据并非易事，存在着很多质量上的问题，除了具有传统数据所有的质量问题外，还包括一些独特的新问题。为了更好地应用大数据，本文对如何进行大数据应用的质量控制进行了初步的研究。主要内容包括以下三个方面：一是对什么是大数据质量、受哪些因素影响、可能存在哪些质量问题进行了探讨；二是从做好理论准备、建立质量控制方案、重视对小数据研究、加强大数据管理、加强大数据人才培养和加强大数据法制建设六个方面，提出了大数据应用的质量控制的基本想法；三是对大数据应用中需要引起注意的几个方面进行了讨论，并结合例子进行了阐释。     

Urban Mortgage Loan Statistics in One Life Company

For much of 1970 and during the early part of 1971 some forty members of the American Statistical Association, working as seven task force groups under the guidance of a special Steering Committee, gave much time and thought to an examination of the objectives and activities of ASA. Their purpose was to try to determine what those objectives should be and how best to accomplish them. After careful review and study by the Board of ASA, the task force and steering committee findings and recommendations were adopted, modified or supplemented and issued as an integrated Board report under the title of A Study of Future Goals of ASA.     

A review of nonparametric ranked-set sampling methodology

Ranked-set sampling is an alternative to random sampling for settings in which measurements are difficult or costly. Ranked-set sampling utilizes information gained without measurement to structure the eventual measured sample. This additional information yields improved properties for ranked-set sample procedures relative to their simple random sample counterparts. We review the available nonparametric procedures for data from ranked-set samples. Estimation of the distribution function was the first nonparametric setting to which ranked-set sampling methodology was applied. Since the first paper on the ranked-set sample empirical distribution function, the two-sample location setting, the sign test, and the signed-rank test have all been examined for ranked-set samples. In addition, estimation of the distribution function has been considered in a more general setting. We discuss the similarities and differences in the properties of the ranked-set sample procedures for the various settings     

A family of measures to evaluate scale reliability in a longitudinal setting

Summary.  The concept of reliability denotes one of the most important psychometric properties of a measurement scale. Reliability refers to the capacity of the scale to discriminate between subjects in a given population. In classical test theory, it is often estimated by using the intraclass correlation coefficient based on two replicate measurements. However, the modelling framework that is used in this theory is often too narrow when applied in practical situations. Generalizability theory has extended reliability theory to a much broader framework but is confronted with some limitations when applied in a longitudinal setting. We explore how the definition of reliability can be generalized to a setting where subjects are measured repeatedly over time. On the basis of four defining properties for the concept of reliability, we propose a family of reliability measures which circumscribes the area in which reliability measures should be sought. It is shown how different members assess different aspects of the problem and that the reliability of the instrument can depend on the way that it is used. The methodology is motivated by and illustrated on data from a clinical study on schizophrenia. On the basis of this study, we estimate and compare the reliabilities of two different rating scales to evaluate the severity of the disorder.     

The Many Facets of Statistics Education: 175 Years of Common Themes

The American Statistical Association's primary founder, Lemuel Shattuck, was driven by a passion for collecting and disseminating accurate information on vital statistics, public health, and other statistically related concerns. The 175th anniversary provides an opportunity to reflect on the education-related reasons ASA was founded and what it has done in education since its founding, especially in the past 25 years since the 150th anniversary. An examination of early and more recent issues of the ASA's journals reveals some common themes that have recurred over the past 175 years. We discuss what those themes are and what the ASA is doing to address them currently, and then conclude by discussing what ASA members can do to help.     

Selection of variables and neighborhoods for spatial enhancement of thermal infrared images

The Landsat TM sensor tor rhrrmal infrared measurement has lower spatial resoltion than that of other six measurements. Nishii et al (1996) proposed a procedure to corrct the measurement by a linear combination of remaining high-resolution measurements. To find an efficient combinationof measurements, the averaged information) criteria based on AIC are purposed. Then the efficiency of the procedure is assessed through SSE by using actual TM data.     

Robust design of adaptive control charts for manual manufacturing/inspection workstations

Often the manufacturing and the inspection workstations in a manufacturing process can coincide: thus, in these workstations the statistical process control (SPC) procedure of collecting sample statistics related to a critical-to-quality parameter is a task required to be done by the same worker who has to complete the working operations on a part. The aim of this study is to design a local SPC inspection procedure implementing an adaptive Shewhart control chart locally managed by the worker within the manufacturing workstation: the economic design of the inspection procedure is constrained by the expected number of false alarms issued and is restricted to those designs feasible with respect to the available shared labour resource. Furthermore, a robust approach that models the shift of the controlled parameter mean as a random variable is taken into account. The numerical analysis allows the most influencing environmental process factors to be captured and commented upon. The obtained results show that a few process operating parameters drive the choice of performing a robust optimization and the selection of the optimal SPC adaptive procedure.     

腐败的主观测评方法——以腐败感知指数为例

腐败测评是反腐败研究的重要组成部分,中国的腐败测评体系亟待发展。腐败测评有主观测评法和客观测评法两种研究思路。从统计机理和统计应用情况看,腐败的主观测评方法处于腐败测评研究的主流地位。本文介绍了腐败主观测评方法的基本思路、研究进展,并以腐败感知指数为例对其理论与应用情况进行了说明。     

Perturbed robust linear estimating equations for confidentiality protection in remote analysis

National statistical agencies and other data custodians collect and hold a vast amount of survey and census data, containing information vital for research and policy analysis. However, the problem of allowing analysis of these data, while protecting respondent confidentiality, has proved challenging to address. In this paper we will focus on the remote analysis approach, under which a confidential dataset is held in a secure environment under the direct control of the data custodian agency. A computer system within the secure environment accepts a query from an analyst, runs it on the data, then returns the results to the analyst. In particular, the analyst does not have direct access to the data at all, and cannot view any microdata records. We further focus on the fitting of linear regression models to confidential data in the presence of outliers and influential points, such as are often present in business data. We propose a new method for protecting confidentiality in linear regression via a remote analysis system, that provides additional confidentiality protection for outliers and influential points in the data. The method we describe in this paper was designed for the prototype DataAnalyser system developed by the Australian Bureau of Statistics, however the method would be suitable for similar remote analysis systems.     

POT模型在巨灾损失预测中的应用——基于MCMC方法的估计

极值统计学主要研究随机事件极端情况的统计规律性。运用POT模型拟合中国暴雨损失数据,确定损失超出量的分布形式。实证分析表明,借助POT模型对巨灾风险损失分布进行估计是较为合理的,但当数据量较小时,使用基于Gibbs抽样的MCMC方法估计POT模型的参数,可以解决样本数据不足导致的极大似然估计中误差增大的问题。     

Bayesian discrete latent spatial modeling of crack initiation in orthopaedic hip replacement bone cement

In this paper, we propose a spatial model for the initiation of cracks in the bone cement of hip replacement specimens. The failure of hip replacements can be attributed mainly to damage accumulation, consisting of crack initiation and growth, occurring in the cement mantle that interlocks the hip prosthesis and the femur bone. Since crack initiation is an important factor in determining the lifetime of a replacement, the understanding of the reasons for crack initiation is vital in attempting to prolong the life of the hip replacement. The data consist of crack location coordinates from five laboratory experimental models, together with stress measurements. It is known that stress plays a major role in the initiation of cracks, and it is also known that other unmeasurable factors such as air bubbles (pores) in the cement mantle are also influential. We propose an identity-link spatial Poisson regression model for the counts of cracks in discrete regions of the cement, incorporating both the measured (stress), and through a latent process, any unmeasured factors (possibly pores) that may be influential. All analysis is carried out in a Bayesian framework, allowing for the inclusion of prior information obtained from engineers, and parameter estimation for the model is done via Markov chain Monte Carlo techniques.     

数字贸易测度的概念架构、指标体系和测度方法初探

数字贸易是构建“以国内大循环为主体、国内国际双循环相互促进”的新发展格局的新模式和新业态,也是各国参与国际竞争与合作的重要领域。然而,国际社会对数字贸易概念的认识还比较模糊,直接影响着数字贸易市场拓展和规则制定,数字贸易测度也成为国际贸易统计领域具有挑战性课题。本文在回顾和梳理国际社会关于数字贸易概念和测度方法既有论述的基础上,提出了数字贸易的“二元三环”概念架构,构建了测度数字贸易规模的指标体系,开发了以“实际数字交付比率”为关键的数字贸易测度法,并使用中国“两化融合”平台数据库的数据,对中国2018—2019 年数字贸易进出口总额进行了试测度。本文的研究成果对我国数字贸易测度研究以及有关部门建立数字贸易统计监测制度具有借鉴作用。     

A Bayesian hierarchical model for photometric red shifts

Summary.  The Sloan digital sky survey is an extremely large astronomical survey that is conducted with the intention of mapping more than a quarter of the sky. Among the data that it is generating are spectroscopic and photometric measurements, both containing information about the red shift of galaxies. The former are precise and easy to interpret but expensive to gather; the latter are far cheaper but correspondingly more difficult to interpret. Recently, Csabai and co-workers have described various calibration techniques aiming to predict red shift from photometric measurements. We investigate what a structured Bayesian approach to the problem can add. In particular, we are interested in providing uncertainty bounds that are associated with the underlying red shifts and the classifications of the galaxies. We find that quite a generic statistical modelling approach, using for the most part standard model ingredients, can compete with much more specific custom-made and highly tuned techniques that are already available in the astronomical literature.     

SPC—a team effort for process improvement across four Area Control Centres

This paper describes an innovative application of statistical process control to the online remote control of the UK's gas transportation networks. The gas industry went through a number of changes in ownership, regulation, access to networks, organization and management culture in the 1990s. The application of SPC was motivated by these changes along with the desire to apply the best industrial statistics theory to practical problems. The work was initiated by a studentship, with the technology gradually being transferred to the industry. The combined efforts of control engineers and statisticians helped develop a novel SPC system. Having set up the control limits, a system was devised to automatically update and publish the control charts on a daily basis. The charts and an associated discussion forum are available to both managers and control engineers throughout the country at their desktop PCs. The paper describes methods of involving people to design first-class systems to achieve continual process improvement. It describes how the traditional benefits of SPC can be realized in a 'distal team working', and 'soft systems', context of four Area Control Centres, controlling a system delivering two thirds of the UK's energy needs.