直线相关分析中,对相关系数作假设检验,其目的是() A.检验两总体相关系数是否相等

题型:单项选择题 A1型题

问题:

直线相关分析中,对相关系数作假设检验,其目的是()

A.检验两总体相关系数是否相等

B.推断两变量间是否存在直线相关关系

C.检验相关系数r是否等于0

D.推断两变量间相关方向

E.推断两变量间密切程度

考点:疾病控制基础知识卫生统计学卫生统计学题库
题型:单项选择题 A1型题

阅读理解。

     Is it hard for you to get up early and get ready for classes? Some students at Winter Park High School just

quickly get up and go to class in their own bedrooms. Of course, their teachers and classmates do not see

them because all their class work is on the computer.

     The Florida High School, the state's only on-line school, has 250 students who are taking classes at home

by computers.

     "I'm a lot more comfortable at home," said Luke Levesque, a 16-year-old who is taking a computer class

on line. He thinks (A) the school's computer lab is so noisy that he can't study well." Home is much better,"

he says. 

     Students in this first on-line program take classes in math, American government, chemistry, computer, and Web-page design. They also have to go to regular (正规的) school to attend other classes.

     When a student is ready to begin in class, he or she (B) _______ the computer, reads the teacher's

instructions, and begins working on the lesson for the day. What happens if a student has a question for the

teacher? Or the teacher wants to say something about the work a students is doing? The student and the

teacher talk to each other every day through e-mail or by telephone.

      Is it easy for students to cheat on tests (考试作弊) when they're working at home? (C) The teachers have

already thought about this. They make students take their final exams in person in the classroom.

     "You see most of the same things on-line that you see in a regular classroom," says teacher Linda Hayes.

     If this first on-line program goes well, in three years Florida High School students will be able to take all

their classes by computer. When that happens, students will be able to get their high school diplomas (毕业证

书) without having to (D) 走进教室.

1. 将画线部分(A)改写成 the school's computer lab is _______ noisy for _______ to study well.

2. 在(B)的空白处填入一个适当的词语。

    __________________________________________________

3. 将画线部分(C)译成汉语。

   __________________________________________________

4. 将画线部分(D)译成英语。

   __________________________________________________

5. 在正文中找出能够说明主题的短语。

   __________________________________________________

题型:单项选择题 A1型题

下列有关复苏后脑部的叙述,哪项正确()

A.每上升1℃体温会使脑部的新陈代谢率上升约20%

B.脑部的新陈代谢可能会因癫癎而增加300%~400%

C.给予甘露醇时,应检查血渗透压,使其不超过350mOsin

D.在没有颅内压力增高的情形下,应将PaCO2控制在25mmHg左右

E.轻度躁动有利于血液循环,从而有利于脑功能恢复

题型:单项选择题 A1型题

下列说法错误的是()。

A、各专业应急机构每年至少组织一次安全生产事故灾难应急救援演练

B、国务院安委会办公室对安全生产事故灾难应急预案实施过程进行监督

C、县级以下人民政府应建立紧急救援物资储备制度

D、有关部门要积极宣传,提高公众自救、互救能力

题型:单项选择题 A1型题

观察脑出血患者时,发现哪种情况常提示出血已止()

A.瞳孔先缩小后散大

B.意识障碍变浅

C.血压继续升高

D.呼吸不规则

E.脉搏变慢

题型:单项选择题 A1型题

前臂缺血性肌挛缩,多见于

A.肱骨髁上骨折

B.尺骨骨折

C.胫骨骨折

D.股骨骨折

E.Colles骨折

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