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Text 3 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 modem descriptive statistics. From the influence of the father came modem inferentical statistics, which is based squarely on theories of probability. Descriptive statistics involves tabulating, depicting, and describing collections of data. These data may be either quantitative, such as measures of height, intelligence, or grade level—variables that are characterized by an underlying continuum or the data may represent qualitative variable, 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 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 difficulties for the unaided human mind. This general class 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 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 knowledge of the characteristics of only a sample of the population. Why does the author mention the "mother" and "father" in the first paragraph
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With the passage of time, the wave of change also spread to cities. The expression "one’s (67) on marriage" began to appear, as did the concept of "marriage as one of life’s many (68) ." The (69) of men still unmarried in their thirties reached about twenty percent in the national (70) taken in 1985, and the (71) of a "hard-to-get-married era" began to be much talked about. The figure apparently (72) 30 percent in 1995. (73) , the highest rate of male singles in their thirties was (74) in Tokyo, including that the (75) number of unmarried men was no longer a (76) rural problem. What about women The proportion of unmarried women in the 25 - 29 age (77) bracket has been increasing (78) about 5 percent every five years (79) it is now nearly 50 percent. What are the real reasons women (80) not to marry Early on, two were cited: women are now better educated and more women are interested in working outside the home. A Ministry of Education survey (81) in 1989 found that 35.8 percent of male high school graduates (82) to college or university (including junior college) — less than the 36.8 percent for female graduates. This was the first time (83) the ministry started such surveys that women had (84) men in going (85) higher education. (86) , the proportion of women with jobs outside the home reached 49.5 percent in 1989.
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E-mail Imagine being able to send a letter to someone, anywhere in the world, that included pictures and sounds as well as written words, and not even have to put a stamp on it. With e-mail you can do just that. E-mail allows you to send messages quickly and easily to other people using computers rather than the postal service. To the Internet user, the ordinary post is known as "snail mail" because it is so much slower than e-mail, which can deliver its message to the other side of the world in seconds. In some ways, e-mail is like a cross between a letter and a telephone call. You type a note or a letter on your screen and then you send it down the telephone line to another person for as little as it costs you to call your service provider. Whether your message is going to Calgary in Canada or to Copenhagen in Denmark, it will cost the same. You can even attach a file from your computer, whether it be a sound, an image or a text, to your e-mail message. E-mail addresses are made up of two distinct parts, separated by the "@" sign. The first part of the address identifies the specific user. Many people use their names, or their initials or a nickname. After the @ sign comes the host address or node name, which is the actual place where the user’s electronic mailbox is situated. Here is an example. My e-mail address is "november@dircon.co.uk." I picked "November" because that was the month in which I was born, and "dircon" is the Direct Connection, my service provider, a commercial company based in the UK. Easy, isn’t it When a new user joins the Internet for the first time, he or she will get an e-mail address that allows the user both to send and receive messages. Just as you need to put the correct address on an envelope to make sure it gets to the right place, so you must also put the correct e- mail address on your electronic correspondence. Computers are not so understanding as postmen and women, who can sometimes work out where a wrongly addressed letter is meant to go. If you make a slight mistake with your address, your message will simply be bounced right back to you. How do you find out what someone’s e-mail address is Naturally, the easiest and best way is simply to ask them. Because there is no one in charge of the whole Internet and because it is expanding so rapidly, there is no complete record anywhere of everyone who is connected. When someone sends you a message via e-mail, it will be stored on the computer at your service provider, or if your school has its own connection to the Internet, on the main server. Once you have logged on to the Net you can launch your e-mail program. Eudora is one of the most popular and easy-to-use programs and is available for both Macintosh and IBM compatibles. There is a version that you can download from the Internet. Many programs will automatically search for new messages when they are first launched. E-mail has obvious advantages for schools and businesses that want to keep track of their messages. For example, it allows you to quote all or part of the message you are replying to, without having to type it all out again. The handy thing about this feature is that if you are answering questions, you can keep them in your reply. This saves the other person having to refer back to the original documents when he or she gets your reply. Another thing e-mail allows you to do is to forward a message on to someone else. If someone sends you a piece of information that you feel would be of interest to another person, you can send a copy of the message to him. Again this is invaluable for large organizations that might have offices all over the world. For example, someone in the London office might send a query or a new idea to someone else in New York in the United States. He, realizing that this is something that another person in Sydney in Australia has been working on, passes the message on almost instantly. If you want to send a graphics file (one containing a picture), a sound file, a document or a video clip with your e-mail, you can do that too. Most e-mail readers have a menu item that allows you to attach a file using an instruction, or command, called "attach file" or something similar. To do this the e-mail program uses Multipurpose Internet Mail Extensions (MIME) to attach the file and process it into the chunks of the right size for sending via e-mail. If the Internet has any lasting effect on our lives it may well be through the use of e-mail. As we have seen, there are many advantages that e-mail enjoys over snail mail in terms of speed and usefulness. It also has a big advantage over a message taken over the telephone — you cannot print out a telephone call. Probably more people join the Internet to get access to e-mail than for any other reason. E-mail is easy to use and it saves time and money. The differences in time in different parts of the world do not matter when sending e-mail. It is a twenty-four-hour service that allows you to send information at any time of the day or night. If you want to know what it is like to live in the Arctic, send a message to a school in Alaska and find out. If a company wants to know how much it costs to print a book in the Far East, it can e-mail some printers in Singapore or Hong Kong. The message will be there the next time someone at the other end switches on his or her computer and logs on. No one has to be there to answer the telephone. It does not matter if they are in bed when you send the message, or you are watching a film at the cinema when they send a reply. If you want to make friends on the Internet, it is just as well to have good manners. One of the most important rules to follow is, DON’T TYPE ALL OF YOUR MESSAGES IN CAPITAL LETTERS. It is the Internet equivalent of shouting the telephone. Be careful how you say things. Because it is so fast and easy to send e-mail messages, people often do not bother to check what they have written before pressing the "send" button. Write your e-mail with the same care and attention you would use for other forms of communication. Reply to your messages promptly. If someone has taken the trouble to write to you, take the trouble to write back. It is only polite. It is suggested by the writer that we should not write our e-mails all in ______letters.
Questions 22 to 25 are based on the conversation you have just heard.
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