沃特·阿曼德·休哈特Walter A. Shewhart

沃特·阿曼德·休哈特的父母是Esta Barney和Anton Shewhart。他就读于伊利诺伊大学，1913年获得A.B.学位，1914年获得A.M.学位。1914年8月4日，他与Edna Hart结婚。他搬到乔治·伯克利的加利福尼亚大学从事物理学研究，并在那里于1915-16年期间担任Whiting fellow。他于1917年从加利福尼亚大学获得博士学位。他曾在伊利诺伊大学和加利福尼亚大学任教，并短暂担任拉克罗斯的威斯康星师范学校的物理系主任。这所学校于1909年开办，1927年更名为拉克罗斯州立师范学院，然后在1964年再次更名为威斯康星州立大学-拉克罗斯。休哈特于1918年加入西部电气公司，该公司是贝尔电话公司的硬件制造商。

休哈特于1918年加入的是位于霍桑的西部电气公司的检验工程部。他在那里研究统计工具，以检查何时必须对过程采取纠正措施。他的著作涉及工业过程的统计控制以及在科学测量过程中的应用。他开发的控制图技术已被广泛采用。他的贡献在[8]中有更详细的解释：-

到世纪之交时，西部电气已经培训了人员作为检验员，以确保规格和质量标准，从而避免将不良产品发送给客户。在1920年代，西部电气的休哈特博士将制造质量提升到了一个新的水平——采用统计技术来控制过程，以最小化缺陷产出。当休哈特博士于1918年加入霍桑的检验工程部时，工业质量仅限于检验成品和移除有缺陷的物品。这一切在1924年5月发生了变化。休哈特博士的老板George Edwards回忆道：

“休哈特博士准备了一份仅一页左右的小备忘录。那一页中约三分之一用于一个简单的图表，我们今天都会认出它是一张示意性的控制图。那个图表，以及它前后的简短文字，阐述了今天我们称之为过程质量控制所涉及的所有基本原则和考虑。”

休哈特先生观察到了过程控制现代科学研究的诞生。同年，休哈特博士创建了制造过程的第一个统计控制图，其中涉及统计抽样程序。休哈特在1931年出版的《制成品质量的经济控制》一书中发表了他的发现。

贝尔电话实验室成立于1925年，休哈特在实验室成立时转到那里工作，直到1956年退休。在此期间，他将兴趣扩展到统计学的更广泛应用。在此期间，他在Bell System Technical Journal上发表了许多文章论文。此外，他于1931年在American Mathematical Monthly上发表了Random sampling。1939年，他出版了重要著作Statistical Method from the Viewpoint of Quality Control。阅读出版者对这本书的描述很有趣：-

统计方法在大规模生产中的应用使得原材料和制造过程得到最有效的利用，实现经济生产，并使制成品达到最高质量标准。在这本经典著作中，基于1938年向农业部研究生院所作的一系列开创性讲座，休哈特博士阐明了在实现统计控制、建立容差限、呈现数据以及规定准确度和精密度方面有效使用统计方法的基本原理和技术。

在第一章中，致力于统计控制，作者广泛定义了质量控制的三个步骤：规格、生产和检验；然后他概述了质量控制的历史背景。接下来是对统计控制的物理和数学状态的严格讨论，作为操作的统计控制，统计控制的意义以及统计在大规模生产中的未来。

第二章对确定变异限度的问题作了发人深省的论述，包括容限的含义、在最简单情形和实际情形中确定容限，以及标准的测量方法。第三章探讨物理性质和常数的测量结果的表述。所考虑的主题包括作为原始数据给出的测量、原始数据的特征、对原始数据的汇总（既通过对称函数，也通过巴夫尼提·列波维奇·切比雪夫定理）、作为有意义的预测给出的测量，以及作为知识给出的测量。

休哈特处理规定准确度和精密度的问题——准确度和精密度的含义、操作意义、可验证程序、形成判断所需的最小证据量等。

在这本书中，休哈特问道：-

统计实践乃至整个科学，能从工业质量控制的经验中学到什么？

他在这本书中写道：-

以物理操作来定义随机，对统计理论的数学运算毫无影响，这一点众所周知，因为就这些数学运算而言，随机纯粹就是一个未定义项。形式化的抽象数学理论有其独立、有时孤独的存在。但当像随机这样一个未定义的数学术语被赋予明确的物理操作意义时，它就具有了经验和实践意义。于是，每一个涉及这个数学上未定义概念的数学定理都可以被赋予如下预测形式：如果你如此这般做，那么如此这般就会发生。

尽管整个职业生涯都在工业界工作，休哈特仍与学术机构保持联系，1930年在霍博肯的史蒂文斯理工学院担任应用统计学讲师，1932年在伦敦大学讲学，1938年在美国农业研究生院讲学。他于1954年是罗格斯大学的名誉教授，并在1941-48年期间是普林斯顿数学系咨询委员会的成员。在1944-46年期间，他在国家研究委员会任职，并担任弗瑞兹·约翰 Wiley and Sons的Mathematical Statistics Series编辑超过20年。

休哈特因其重要贡献获得了许多荣誉。他是数理统计学会的创始人，被选为会士，并于1936年担任一届副主席，1936年至1944年担任主席。他还是美国质量控制学会的创始人。该学会于1947年授予他首位荣誉会员，并让他成为首位获得其休哈特奖章的人。引文如下：-

颁发奖章之举将公众关注的焦点集中在获奖者身上，清晰地揭示出为他赢得同行尊敬的那些品质。是什么品质促使我们如此尊敬一个人，以至授予他奖章？首先，他必须具备智力才能，使他能够驱散一点始终笼罩我们的无知阴云。其次，他必须具备慷慨的精神，促使他表达和重述自己的开创性思想，使同行其他成员能从中受益。最后，他必须具备那种真正教育者特有的人情温暖，使学生或追随者，甚至那些只能间接向他学习的人，都对他怀有爱戴。所有这些品质在休哈特博士身上都得到了卓越的体现。

他被选为美国统计协会会士、国际统计学会会士和皇家统计学会会士。他还被选为美国科学促进会（1942-49年间在理事会任职）、计量经济学会和纽约科学院的成员。他于1945年担任美国统计协会主席一职，并于1954年被授予美国机械工程师学会的霍利奖章。加尔各答的印度统计研究所授予他荣誉博士学位。

Walter Shewhart's parents were Esta Barney and Anton Shewhart. He attended the University of Illinois receiving an A.B. in 1913, then an A.M. degree in 1914. On 4 August 1914, he married Edna Hart. He moved to the University of California at Berkeley to undertake research in physics, and while there was a Whiting fellow during 1915-16. He was awarded his doctorate from the University of California in 1917. He taught at the universities of Illinois and California and, for a short time, was Head of Physics at the Wisconsin Normal School in La Crosse. This School opened in 1909, was renamed La Crosse State Teachers College in 1927, and then was again renamed to Wisconsin State University - La Crosse in 1964. Shewhart joined the Western Electric Company in 1918, the company being the manufacturer of hardware for the Bell Telephone Company.

It was the Inspection Engineering Department of the Western Electric Company at Hawthorne that Shewhart joined in 1918. He worked there on statistical tools to examine when a corrective action must be applied to a process. His writings were on statistical control of industrial processes and applications to measurement processes in science. The control chart techniques which he developed have been widely adopted. His contributions are explained in more detail in [8]:-

By the turn of the century, Western Electric had trained individuals as inspectors to assure specification and quality standards, in order to avoid sending bad products to the customer. In the 1920's, Western Electric's Dr Walter Shewhart took manufacturing quality to the next level - employing statistical techniques to control processes to minimize defective output. When Dr Shewhart joined the Inspection Engineering Department at Hawthorne in 1918, industrial quality was limited to inspecting finished products and removing defective items. That all changed in May 1924. Dr Shewhart's boss, George Edwards, recalled:

"Dr Shewhart prepared a little memorandum only about a page in length. About a third of that page was given over to a simple diagram which we would all recognize today as a schematic control chart. That diagram, and the short text which preceded and followed it, set forth all of the essential principles and considerations which are involved in what we know today as process quality control."

Mr Edwards had observed the birth of the modern scientific study of process control. That same year, Dr Shewhart created the first statistical control charts of manufacturing processes, which involved statistical sampling procedures. Shewhart published his findings in a 1931 book, Economic Control of Quality of Manufactured Product.

The Bell Telephone Laboratories were founded in 1925 and Shewhart moved to them when the Laboratories opened and worked there until his retirement in 1956. He expanded his interests to a broader use of statistics over this period. During this period he published many articles papers in the Bell System Technical Journal. In addition, he published Random sampling in the American Mathematical Monthly in 1931. In 1939 he published the important book Statistical Method from the Viewpoint of Quality Control. It is interesting to read the publisher's description of the book:-

The application of statistical methods in mass production makes possible the most efficient use of raw materials and manufacturing processes, economical production, and the highest standards of quality for manufactured goods. In this classic volume, based on a series of ground-breaking lectures given to the Graduate School of the Department of Agriculture in 1938, Dr Shewhart illuminates the fundamental principles and techniques basic to the efficient use of statistical method in attaining statistical control, establishing tolerance limits, presenting data, and specifying accuracy and precision.

In the first chapter, devoted to statistical control, the author broadly defines the three steps in quality control: specification, production and inspection; he then outlines the historical background of quality control. This is followed by a rigorous discussion of the physical and mathematical states of statistical control, statistical control as an operation, the significance of statistical control and the future of statistics in mass production.

Chapter II offers a thought-provoking treatment of the problem of establishing limits of variability, including the meaning of tolerance limits, establishing tolerance limits in the simplest cases and in practical cases, and standard methods of measuring. Chapter III explores the presentation of measurements of physical properties and constants. Among the topics considered are measurements presented as original data, characteristics of original data, summarizing original data (both by symmetric functions and by Chebyshev's theorem), measurement presented as meaningful predictions, and measurement presented as knowledge.

Finally, Dr Shewhart deals with the problem of specifying accuracy and precision - the meaning of accuracy and precision, operational meaning, verifiable procedures, minimum quantity of evidence needed for forming a judgment and more.

In this book Shewhart asks:-

What can statistical practice, and science in general, learn from the experience of industrial quality control?

He wrote in this book:-

The definition of random in terms of a physical operation is notoriously without effect on the mathematical operations of statistical theory because so far as these mathematical operations are concerned random is purely and simply an undefined term. The formal and abstract mathematical theory has an independent and sometimes lonely existence of its own. But when an undefined mathematical term such as random is given a definite operational meaning in physical terms, it takes on empirical and practical significance. Every mathematical theorem involving this mathematically undefined concept can then be given the following predictive form: If you do so and so, then such and such will happen.

Although working in industry for the whole of his career, Shewhart kept links with academic institutions being a lecturer in applied statistics at the Stevens Institute of Technology in Holboken in 1930, lecturing at the University of London in 1932 and at the United States Agricultural Graduate School in 1938. He was an honorary professor at Rutgers University in 1954 and a member of the advisory committee of the Princeton mathematics department during 1941-48. During 1944-46 he served on the National Research Council and for over 20 years he served as editor of the Mathematical Statistics Series of John Wiley and Sons.

Shewhart received many honours for his important contributions. He was a founder of the Institute of Mathematical Statistics, being elected a fellow and serving a term as vice-president in 1936 and president from 1936 to 1944. He was also a founder of the American Society for Quality Control. The Society made him their first honorary member in 1947 and also made him the first to receive their Shewhart Medal. The citation reads:-

The act of awarding the medal focuses the spotlight of public attention on the recipient, revealing in clear light the qualities that have won for him the esteem of his peers. What are the qualities that lead us to so honour a man as to give him a medal? First of all, he must have intellectual ability, enabling him to clear away a little of the dark cloud of ignorance that always surrounds us. Second, he must have the generosity of spirit that leads him to so express and restate his pioneering ideas that other members of his profession may benefit from them. And finally, he must have that warmth of human feeling that marks the true educator, endearing him to his students or disciples, even those who learn from him only remotely. All of these qualities are eminently personified in Dr Walter Shewhart.

He was elected to a fellowship of the American Statistical Association, of the International Statistical Institute, and of the Royal Statistical Society. He was also elected to the American Association for the Advancement of Science (serving on the council during 1942-49), the Econometric Society, and the New York Academy of Science. He served a term as president of the American Statistical Association in 1945, and was awarded the Holley medal of the American Society of Mechanical Engineers in 1954. The Indian Statistical Institute in Calcutta awarded him an honorary doctorate.