单项选择题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.
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 variables, such as sex, college major, or personality type. Large masses of data must generally undergo a process of summarization or reducing to comprehensibly 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 a knowledge of the characteristics of only a sample of the population.

单项选择题An American scientist has found that many images of dinosaurs may be wrong. For years, pictures of the ancient creatures have shown their nose openings near the top of the head. The new study suggests the dinosaurs’ nostrils were just above the mouth.
Dinosaurs used their nostrils to breathe, smell and control their body temperature. The new theory could help explain how the huge creatures were able to survive by using their sense of smell to find food, a mate and possible enemies.
Lawrence Witmer of Ohio University in Athens, Ohio led the study. The publication science reported his findings.
Many of the early dinosaur remains recovered by scientists were from huge creatures called sauropods. Scientists believed that sauropods must have lived in water because their bodies were so huge and their necks were so long.
Nostrils high on the head would have permitted the dinosaurs to breathe while partly under water. The discovery of a sauropod head bone in 1884 added support for this belief. The skull had a large hole at the top of the head.
Professor Witmer says experts learned years later that sauropods generally were not sea creatures. But he says the earlier theory about nostril position was extended to other dinosaurs.
Only dinosaur bones have survived as fossil remains. Scientists have~ never recovered dinosaur remains of soft tissue. Scientists interested in the physical appearance of dinosaurs often study birds and animals similar to the ancient creatures. Professor Witmer examined forty - five kinds of birds, crocodiles and lizards that are the closest living relatives to dinosaurs. He noted the placement of soft tissue through hundreds of x - ray images and by cutting pieces of tissue. Soft tissue leaves markings on bone. Professor Witmer used this information to make a map of the likely position of soft tissue in the dinosaurs’ noses. He found that the birds and reptiles he studied share a common nostril position.
Professor Witmer found that the hole scientists once thought was a nostril in dinosaurs is just one part of the larger nasal passage. He found that the nostrils were farther forward and closer to the mouth. He says this new nostril position was true for all dinosaurs.

单项选择题During the whole of a dark, cloudy day near the end of the year I had been (31) my horse along country roads with little life or beauty. (32) evening fell, I found myself within view of the House of Usher. I do not know why, but my first sight of it (33) my heart heavy. I stopped my horse (34) the edge of the black and quiet lake that lay beside the building. (35) down into the water , I saw a (36) of the dark old house and the dying trees in it. There was something in that reflection that (37) fear to my heart, though I could not tell what (38) .
I looked up at the old house itself, which was made (39) stone. None of the wall had fallen, but many stones (40) to be loose. There (41) to be a break in the front of the building, (42) down the wall (43) the top until it had lost in the dark water of the lake.
I had come to visit a childhood friend , Roderick Usher. I (44) him for many years , and I knew very (45) about him. But he had written me a letter, (46) me to come. He was sick in body and in mind ,and he wanted to see me,his.best and oldest friend. I could not refuse. But now, something about the house frightened me. The room (47) the friend met me was almost dark , but I could see that he had changed very much (48) our last meeting many years ago. He looked ill, and there was a wild look in his eyes. He was nervous--he would be active for a few moments and then Suddenly he Would be very, quiet. He told me that he bad a family illness which could not be cured.
The worst part was his fear of everything. The light hurt his eyes, and even a small noise filled him (49) fear. Most of all he was afraid of (50) . Fear had become part of his life, such as it was now.

单项选择题The Japanese are fascinated by automata and new inventions. Japanese children are used to friendly robots in their comics, in toys, and in TV animated cartoons. When as adults they join the workforce, robots mean that there is no need to import cheap foreign labor, as happens in many other parts of the world. There is no need for humans to put up with dirty, mind-deadening mechanical work the robot does it all without complaint, around the clock. Robots don’ t go on strike over tea breaks they don’ t have tea, or any other kind of breaks: they work, day and night, without having to be paid overtime, without making mistakes. Human tasks are subject to human error: robot error seldom or never occurs except as a result of human error!
In Japan, robots are almost respected for their virtues. When a new robot is introduced to a small suburban factory, a Shinto priest is invited to inaugurate it. He inaugurates the robot with words along the lines of "Welcome to our co-worker, we hope you’ II help him settle in. " No one laughs.
FANUC demonstrates the Japanese tendency to conform particularly strikingly. The founder of FANUC, Dr. Inaba, has created an army that makes no distinction between blue-collar, white-collar and steel-collar worker: everyone, including the warlord himself, is dressed in yellow clothing issued free by the company. Perhaps to make up for the boring nature of the work, there are a number of other company perks. Company benefits, including pay, are much higher than in similar companies in Japan. Travel to and from work is provided free in the company’ s yellow buses. However, workers are expected to put in demanding unpaid "overtime. " There is a clock in the product development laboratory set to run at ten times the normal speed, the remind everyone that the company is on a war footing.
As we watched Dr. Inaba’ s yellow helicopter soar away to Narita airport, we couldn’ t help thinking that his dream of world domination in robotics and allied applications might be more elegantly achieved if he had also thought to program his robots to whistle while they work.

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