问题 单项选择题 A1型题

一次肺癌研究中,一名医生访视200名病例,一名护士访视200名对照,病例和对照来自同一所医院,并按性别、年龄、种族进行配比,结果发现50%的肺癌患者是重度吸烟者,而对照仅30%是重度吸烟者,差别有统计学意义,有人据此得出结论,肺癌与重度吸烟有联系,此推论()

A.正确

B.不正确,因为不是根据率来判断

C.不正确,因为病例组和对照组在有关的特征上不可比

D.不正确,因为对统计学的意义的解释不确切

E.不正确,因为可能存在观察偏倚

答案

参考答案:E

单项选择题
阅读理解

阅读理解。

     MySpace, the social networking website, is different from other websites which only provide stories about

other people. MySpace is a place that allows you to broadcast your own stories and persona information to as

many people as you like. Started two years ago, it is a big source of information for and about American kids.

     Teenagers and their parents feel very differently about it. Teens are rushing to join the site, not sharing their

parents' worries. It signals yet another generation gap in the digital era.

     For teenagers, it is a reliable network to keep in touch with their friends. They will often list their surnames,

birthdays, after-school jobs, school clubs, hobbies and other personal information.

     "MySpace is an easy way to reach just about everyone. I don't have all the phone numbers of all my

acquaintances. But if I want to get in touch with one of them, I could just leave them a message on MySpace."

said Abby Van Wassen. She is a sixteen-year-old student at Woodland Hills High of Pittsburgh, Pennsylvania.

     Parents on the other hand are seriously concerned about the security problems of MySpace.

     "Every time we hold a parents meeting, the first question is always about MySpace," said Kent Gates, who

travels the country doing Internet safety seminars (研讨会). The National Center for Missing and Exploited

Children has received at least 288 MySpace-related complaints, according to Mary Beth Buchanan, a lawyer in

Pittsburgh.

     "Your profile on MySpace shows all your personal information to anyone on the Web. And MySpace even

lists this information by birthplace and age. It's like a free checklist for troublemakers and it endangers children,"

Buchanan said.

1. From the passage we can learn that MySpace ____.

A. brings about the generation gap

B. is very careful about people's privacy

C. encourages you to list your personal information

D. lists the telephone numbers of your friends

2. Why are some parents against MySpace?

A. Because MySpace has a bad influence on their children.

B. Because they don't want to pay so much money for MySpace.

C. Because it takes up too much of their children's spare time.

D. Because troublemakers can easily approach their children through the site.

3. What can we infer from "Every time we hold a parents meeting, the first question is always about MySpace"?

A. MySpace has become a top issue troubling parents.

B. MySpace often holds parents meetings.

C. MySpace is quite popular-with parents.

D. Parents have lots of questions about the website.

4. The writer's attitude towards MySpace is ____.

A. negative

B. positive

C. optimistic

D. objective