数学专业英语－Statistics

yunjiang · 发表于 2004-5-6 09:34:59

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>The term statistics is used in either of two senses.In common parlance it is generally employed synonymously with the word data.Thus someone may say that he has seen”statistics of industrial accidents in the United States.” It would be conducive to greater precision of meaning if we were not to use statistics in this sense,but rather to say “data (or figures ) of industrial accidents in the United States.”
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>“Statistics” also refers to the statistical principles and methods which have been developed for handling numerical data and which form the subject matter of this text.Statistical methods,or statistics, range form the most elementary descriptive devices, which may be understood by anyone , to those extremely complicated mathematical procedures which are comprehended by only the most expert theoreticians.It is the purpose of this volume not to enter into the highly mathematical and theoretical aspects of the subject but rather to treat of its more elementary and more frequently used phases.
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>Statistics may be defined as the collection, presentation, analysis, and interpretation of numerical data.The facts which are dealt with must be capable of numerical expression.We can make little use statistically of the information that dwellings are built of brick, stone, wood, and other materials; however, if we are able to determine how many or what proportion of,dwellings are constructed of each type of material, we have numerical data suitable for statistical analysis.
Statistics should not be thought of as a subject correlative with physics, chemistry, economics, and sociology. Statistics is not a science; it is a scientific method. The methods and procedures which we are about to examine constitute a useful and often indispensable tool for the research worker. Without an adequate understanding of statistics, the investigator in the social sciences may frequently be like the blind man groping in a dark closet for a black cat that isn’t there. The methods of statistics are useful in an ever---widening range of human activities, in any field of thought in which numerical data may be had.
In defining statistics it was pointed out that the numerical data are collected, presented, analyzed, and interpreted. Let us briefly examine each of these four procedures.
COLLECTION Statistical data may be obtained from existing published or unpublished sources, such as government agencies, trade associations, research bureaus, magazines, newspapers, individual research workers, and elsewhere. On the other hand, the investigator may collect his own information, going perhaps from house to house or from firm to firm to obtain his data. The first-hand collection of statistical data is one of the most difficult and important tasks which a statistician must face. The soundness of his procedure determines in an overwhelming degree the usefulness of the data which he obtains.
It should be emphasized, however, that the investigator who has experience and good common sense is at a distinct advantage if original data must be collected. There is much which may be taught about this phase of statistics, but there is much more which can be learned only through experience. Although a person may never collect statistical data for his own use and may always use published sources, it is essential that he have a working knowledge of the processes of collection and that he be able to evaluate the reliability of the data he proposes to use. Untrustworthy data do not constitute a satisfactory base upon which to rest a conclusion.
It is to be regretted that many people have a tendency to accept statistical data without question. To them, any statement which is presented in numerical terms is correct and its authenticity is automatically established.
PRESENTATION Either for one’s own use or for the use of others, the data must be presented in some suitable form. Usually the figures are arranged in tables or presented by graphic devices.
ANALYSIS In the process of analysis, data must be classified into useful and logical categories. The possible categories must be considered when plans are made for collecting the data, and the data must be classified as they are tabulated and before they can be shown graphically. Thus the process of analysis is partially concurrent with collection and presentation.
There are four important bases of classification of statistical data: (1) qualitative, (2) quantitative, (3) chronological, and (4) geographical, each of which will be examined in turn.
Qualitative When, for example, employees are classified as union or non—union, we have a qualitative differentiation. The distinction is one of kind rather than of amount. Individuals may be classified concerning marital status, as single, married, widowed, divorced, and separated. Farm operators may be classified as full owners, part owners, managers, and tenants. Natural rubber may be designated as plantation or wild according to its source.
Quantitative When items vary in respect to some measurable characteristics, a quantitative classification is appropriate. Families may be classified according to the number of children. Manufacturing concerns may be classified according to the number of workers employed, and also according to the values of goods produced. Individuals may be classified according to the amount of income tax paid.
Chronological Chronological data or time series show figures concerning a particular phenomenon at various specified times. For example, the closing price of a certain stock may be shown for each day over a period of months of years; the birth rate in the United States may be listed for each of a number of years; production of coal may be shown monthly for a span of years. The analysis of time series, involving a consideration of trend, cyclical period (seasonal ), and irregular movements, will be discussed.
In a certain sense, time series are somewhat akin to quantitative distributions in that each succeeding year or month of a series is one year or one month further removed from some earlier point of reference. However, periods of time—or, rather, the events occurring within these periods—differ qualitatively from each other also. The essential arrangement of the figures in a time sequence is inherent in the nature of the data under consideration.
Geographical The geographical distribution is essentially a type of qualitative distribution, but is generally considered as a distinct classification. When the population is shown for each of the states in the United States, we have data which are classified geographically. Although there is a qualitative difference between any two states, the distinction that is being made is not so much of kind as of location.
The presentation of classified data in tabular and graphic form is but one elementary step in the analysis of statistical data. Many other processes are described in the following passages of this book. Statistical investigation frequently endeavors to ascertain what is typical in a given situation. Hence all type of occurrences must be considered, both the usual and the unusual.
In forming an opinion, most individuals are apt to be unduly influenced by unusual occurrences and to disregard the ordinary happenings. In any sort or investigation, statistical or otherwise, the unusual cases must not exert undue influence. Many people are of the opinion that to break a mirror brings bad luck. Having broken a mirror, a person is apt to be on the lookout for the unexpected”bad luck “ and to attribute any untoward event to the breaking of the mirror. If nothing happens after the mirror has been broken, there is nothing to remember and this result (perhaps the usual result )is disregarded. If bad luck occurs, it is so unusual that it is remembered, and consequently the belief is reinforced. The scienticfic procedure would include all happenings following the breaking of the mirror, and would compare the “resulting” bad luck to the amount of bad luck occurring when a mirror has not been broken.
Statistics, then, must include in its analysis all sorts of happenings. If we are studying the duration of cases of pncumonia, we may study what is typical by determining the average length and possibly also the divergence below and above the average. When considering a time series showing steel—mill activity, we may give attention to the typical seasonal pattern of the series, to the growth factor( trend) present, and to the cyclical behaviour. Sometimes it is found that two sets of statistical data tend to be associated.
Occasionlly a statistical investigation may be exhaustive and include all possible occurrences. More frequently, however, it is necessary to study a small group or sample. If we desire to study the expenditures of lawyers for life insurance, it would hardly be possible to include all lawyers in the United States. Resort must be had to a sample;and it is essential that the sample be as nearly representative as possible of the entire group, so that we may be able to make a reasonable inference as to the results to be expected for an entire population. The problem of selecting a sample is discussed in the following chapter.
Sometimes the statistician is faced with the task of forecasting. He may be required to prognosticate the sales of automobile tires a year hence, or to forecast the population some years in advance. Several years ago a student appeared in summer session class of one of the writers. In a private talk he announced that he had come to the course for a single purpose: to get a formula which would enable him to forecast the price of cotton. It was important to him and his employers to have some advance information on cotton prices, since the concern purchased enormous quantities of cotton. Regrettably, the young man had to be disillusioned. To our knowledge, there are no magic formulae for forecasting. This does not mean that forecasting is impossible; rather it means that forecasting is a complicated process of which a formula is but a small part. And forecasting is uncertain and dangerous. To attempt to say what will happen in the future requires a thorough grasp of the subject to be forecast, up-to-the-minute knowledge of developments in allied fields, and recognition of the limitations of any mechanica forecasting device.
INTERPRETATION The final step in an investigation consists of interpreting the data which have been obtained. What are the conclusions growing out of the analysis? What do the figures tell us that is new or that reinforces or casts doubt upon previous hypotheses? The results must be interpreted in the light of the limitations of the original material. Too exact conclusions must not be drawn from data which themselves are but approximations. It is essential, however, that the investigator discover and clarify all the useful and applicable meaning which is present in his data.

yunjiang · 发表于 2004-5-6 09:35:27

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0cm 0cm 0pt; TEXT-ALIGN: center" align=center>Notes<

0cm 0cm 0pt 72.75pt; TEXT-INDENT: -40.5pt; TEXT-ALIGN: left; tab-stops: list 72.75pt; mso-list: l57 level1 lfo25" align=left>1. It is the purpose of this volume not to enter into the highly mathematical and theoretical aspects of the subject but rather to treat of its more elementary and more frequently used phases.<

0cm 0cm 0pt 72.75pt; TEXT-ALIGN: left" align=left>意思是：本书的目的并不是要深入到这个论题的有关高深的数学与理论的方面，而是要讨论它的更为初等和更为常用的方面，not…but rather 意思是“不是…而是”，而rather than意思是“宁愿…而不”，两者意思相近但有差别（主要表现为强调哪方面的差别）。2. Without an adequate understanding of statistics, the investigator in the social sciences may frequently be like the blind man groping in a dark closet for a black cat that isn’t there.意思是：没有对统计学的适当的理解，社会科学的研究人员就会常常像一个盲人在一个暗室里摸索一只并不存在的黑猫一样，这里investigator 指一般研究人员，请比较与researcher，scientist等词的异同。3. It is essential that he have a working knowledge of the processes of collection and that he be able…这里essential是虚拟形容词，所以后面用he have；he be able…have和be前面省去了should。4. The distinction is one of kind rather than of amount.意思是：这种区别是类型的而不是数量的。5. …the distinction that is being made is not so much of kind as of location. 参看第二课注2关于not so much…as的解释，并比较注4和注5两句。6. （To attempt to say what will happen in the future） requires…of any mechanical forecasting device.括号里的部分为此句的主语，谓语是requires， 后面是三个并列宾语短语。

yunjiang · 发表于 2004-5-6 09:35:41

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0cm 0cm 0pt; TEXT-ALIGN: center" align=center>Exercise<

0cm 0cm 0pt 63pt; TEXT-INDENT: -36pt; TEXT-ALIGN: left; tab-stops: list 63.0pt; mso-list: l32 level1 lfo26" align=left>I. Translate the following passages into Chinese:<

0cm 0cm 0pt 66pt; TEXT-INDENT: -18pt; TEXT-ALIGN: left; tab-stops: list 66.0pt; mso-list: l32 level2 lfo26" align=left>1. Statistical methods, or statistics, range from the most elementary descriptive devices which may be understood by anyone, to those extremely complicated mathematical procedures which are comprehended by only the most expert theoreticians.2. Although a person may never collect statistical data for his own use and may always use published sources, it is essential that he have a working knowledge of the processes of collection and that he be able to evaluate the reliability of the data he proposes to use. II Answer the following questions according to the content of this lesson.1. In defining statistics, what are the four procedures about the numerical data?2. How are the numerical data presented usually?3. Give examples for qualitative differentiation and quantitative classification of statistical data .

yunjiang · 发表于 2004-5-6 09:35:14

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0cm 0cm 0pt; TEXT-ALIGN: center" align=center>Vocabulary<

0cm 0cm 0pt; TEXT-INDENT: 32.25pt; mso-char-indent-count: 3.07; mso-char-indent-size: 10.5pt">Statistics统计学 in tables 列成表<

0cm 0cm 0pt; TEXT-INDENT: 32.25pt; mso-char-indent-count: 3.07; mso-char-indent-size: 10.5pt">Statistical 统计的 tabular列成表的Statistical data统计数据 sample样本Statistical method统计方法 inference推理，推断Original data原始数据 reliance信赖Qualitative定性的 forecasting预测Quantitative定量的 in common parlance按一般说法Chronological年代学的 conducive有帮助的Time series时间序列 grope摸索Cyclical循环的 akin to类似Period周期 apt to易于Periodic周期的 undue不适当的Prognosticate预测 sociology社会学Authenticity可信性，真实性 phase相位；方面Synonymously同义的 categories范畴，类型Correlative相互关系的，相依的 concurrent会合的，一致的，同时发生的

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