2014年6月大学英语四级复习题及答案(第二套)_第4页

　　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 governmental units (state 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.

　　?Descripitive statistics involves tabulating, depicting, and describing collections of data. These data may be either quantitative, such as measures of height, intelligence, or grand 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 from 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 difficulties for the unaided human mind. This

　　general class of problems characteristically involves attempts to make prediction using a sample of observations. For example, a school superintendent wishes

　　to determine of 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 entire district could be estimated fairly accurately from a 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.

　　?36.With what is the passage mainly concerned?

　　?A.The drawbacks of descriptive and inferential statistics.

　　?B.Applications of inferential statistics.

　　?C.The development and use of statistics.

　　?D.How to use descriptive statistics.

　　?37.Why does the author mention the “mother” and “father” in the first paragraph?

　　?A.To point out that parents can teach their children statistics.

　　?B.To introduce inferential statistics.

　　?C.To explain that there are different kinds of variables.

　　?D.To present the background of statistics in a humorous and understandable way.

　　?38.Which of the following is NOT given as an example of qualitative variable?

　　?A.Gender. B.Height.

　　?C.College major. D.Type of personality.

　　?39.Which of the following statements about descriptive statistics is best supported by the passage?

　　?A.It simplifies unwieldy masses of data.

　　?B.It leads to increased variability.

　　?C.It solves all numerical problems.

　　?D.It changes qualitative variables to quantitative variables.

　　?40.According to the passage which is the purpose of examining a sample of a population?

　　?A.To compare different groups.

　　?B.To predict characteristics of the entire population.

　　?C.To consider all the quantitative variables.

　　?D.To tabulate collections of data.