A Study Of William 's Statistical Thought

William Petty is not only a political economist but also a statistician. He was active in the early stages of the classical statistical. He creatively used the arithmetic method to study social and economic problems and extensively application of statistics to analyze the social and economic phenomenon. Petty and John Graunt who was born at the same time were known as the founder of "Political Arithmetick" group. The statistical research methods of this group were in deep contrast with the other school that used text description as the main feature. Even the classical statistics was in the bud, Petty calculated and compared the social and economic phenomena by the simple and rough arithmetic method. Even so, Petty has an important position in statistical thinking, and he has many contributions in the statistical purposes, the research object of statistics and statistical methods. If we study the Petty’s statistical thought, it has important historical significance to sort out the history of development of the statistics.This paper is based on the related data and the interpretation and analysis of Petty’s statistical works to systematically expound his idea of statistical thought, such as 《Political Arithmetick》, 《The Political Anatomy of Ireland》, 《Several Essays in Political Arithmetick》, and so on. The writing ideas of this paper: Firstly, I review the background of Petty’s statistics---the development of statistics at the Seventeenth Century; Secondly, I analyze the root of petty’s statistics, and divide into social background with the influence of philosophical thoughts, and I expound the Number, Weight or Measure; Finally, I elaborate the specific contents of his statistical thought, including the object of statistics and statistical methods, and it is evaluated.This paper is divided into five chapters, and the main contents of each chapter are as follows:The first chapter is to introduce the research status at home and abroad, and review briefly the Petty’s life and works, the significance to study Petty’s statistical thought and this paper will use the research methods.The second chapter is to introduce the current development of statistics at the seventeenth century, including the two important statistical groups during this time. In this chapter, I list the two group representative figures and carry on the comparison to the two groups of statistics.The third chapter is to introduce the origin of Petty’s statistical thought. In this section, I select the three Anglo-Dutch Wars and Cromwell conquest Ireland as the social background. It can be understood the root of statistical purpose and the root of statistical data. Because it facilitated the two important statistical works, 《Political Arithmetick》 and 《The Political Anatomy of Ireland》, and his statistical thought is included in these books. In discussing the root of thought, this chapter lists the effects that Petty contacted to philosophy and mathematics thought and participated in academic activities. And I also discuss the research methods that Petty established in《Political Arithmetick》---Number, Weight and Measure.The fourth chapter is to discuss the object of statistics and his statistical methods. The first section elaborates the meaning of "Political Arithmetick". In the second section, I discuss the object of his statistics. And in the third section, I discuss the Petty’s statistical methods in detail: average, data reasoning, data packets and charts.The fifth chapter is to discuss the influence of petty statistical thought to future generations, and his statistics are reviewed.