There were two widely divergent influences on the early development of statistical methods. Statistics had a mother who was dedicated to keeping orderly records of government units (states and statistics come from the same Latin root status) and a gentlemanly gambling father who relied on mathematics to increase his skill at playing the odds in games of chance. The influence of the mother on the offspring, statistics, is represented by counting, measuring, describing, tabulating, ordering, and the taking of censuses-all of which led to modern descriptive statistics. From the influence of the father came modern inferential statistics, which is based squarely on theories of probability.

Describing collections involves tabulating, depicting and describing collections of data. These data may be quantitative such as measures of height, intelligence or grade level------variables that are characterized by an underlying continuum---or the data may represent qualitative variables, such as sex, college major or personality type. Large masses of data must generally undergo a process of summarization or reduction before they are comprehensible. Descriptive statistics is a tool for describing or summarizing or reducing to comprehensible form the properties of an otherwise unwieldy mass of data.

Inferential statistics is a formalized body of methods for solving another class of problems that present great of problems characteristically involves attempts to make predictions using a sample of observations. For example, a school superintendent wishes to determine the proportion of children in a large school system who come to school without breakfast, have been vaccinated for flu, or whatever. Having a little knowledge of statistics, the superintendent would know that it is unnecessary and inefficient to question each child: the proportion for the sample of as few as 100 children. Thus , the purpose of inferential statistics is to predict or estimate characteristics of a population from a knowledge of the characteristics of only a sample of the population.

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作文地带知识拓展:

• 英语（English）属于印欧语系日耳曼语族西日耳曼语支，最早被中世纪的英国使用，并因其广阔的殖民地而成为世界使用面积最广的语言。英国人的祖先盎格鲁部落是后来迁移到大不列颠岛地区的日耳曼部落之一，称为英格兰。这两个名字都来自波罗地海半岛的Anglia。该语言与弗里斯兰语和下撒克森语密切相关，其词汇受到其他日耳曼语族语言的影响，尤其是北欧语（北日耳曼语），并在很大程度上由拉丁文和法文撰写。

  英语的英文释义：

  English 名词 uk  /ˈɪŋ.ɡlɪʃ/ us  /ˈɪŋ.ɡlɪʃ/

  the language that is spoken in the UK, the US, and in many other countries

  英语

  American/British English

  美式／英式英语

  Do you speak English?

  你会说英语吗？

  English   形容词 adjective   uk  /ˈɪŋ.ɡlɪʃ/ us  /ˈɪŋ.ɡlɪʃ/

  in or relating to the English language

  英语的

  an English teacher

  英语老师

  relating to or from England

  英格兰的;英国的

  English films/food/people

  英国电影／食品／人

  English law

  英格兰法律