在抽样调查研究中,当样本含量逐渐增大时A.标准差逐渐增大 B.标准差逐渐减小 C.以

题型:单项选择题

问题:

在抽样调查研究中,当样本含量逐渐增大时

A.标准差逐渐增大

B.标准差逐渐减小

C.以上均不对

D.标准误逐渐增大

E.标准误逐渐减小

考点:卫生资格考试(中初级)公卫相关专业知识公共卫生主治医师相关专业知识7
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某地区欲在短时间内摸清本地区高血压患病的主要危险因素,计划第一步进行人群基础资料和患病资料的收集,第二步进行危险因素的调查,第三步进行资料的整理分析及形成结论

用上述方法进行危险因素调查时,不可避免的偏倚是

A.回忆偏倚

B.奈曼偏倚

C.报告偏倚

D.测量偏倚

E.失访偏倚

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男性,65岁。因心前区痛4小时来院急诊。心电图示急性广泛前壁心肌梗死伴多源性室早,入院体检:气急不能平卧,血压140/80mmHg,心率120次/分,并有奔马律。两肺散在细湿啰音,伴少量哮鸣音。

病人呼吸困难,考虑存在有()

A.左心衰竭

B.右心衰竭

C.全心衰竭

D.肺部感染

E.泵衰竭

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有一位君主在西方考察时,时而扮作水手,时而扮作木匠,总是在不停地做工。这位君主是()

A.彼得一世

B.康熙大帝

C.路易十四

D.明治天皇

题型:单项选择题

According to the recent forecasts from The Futuristic magazine for 1997 and beyond, the (1) since mid-century, while the population has doubled. As a result, the pressure on natural resources has (2) : Demand for grain has nearly tripled, and (3) has increased nearly fourfold, with carbon emissions rising accordingly. City skylines may (4) in the future. Information technologies are allowing workers to (5) rather than trek to downtown skyscrapers. Consequently, many prestigious office towers (6) , and U. S. builders have stopped putting up structures taller than 30 stories. Education in the Information Age will be (7) and less labor-intensive. Teaching may become more centralized, with a few "star teachers" giving courses via (8) to a national student body. Infotech is producing interactive educational toys and other devices that (9) of mental faculties. Some youngsters may even teach themselves to read before age 3. Future education will not end with (10) in high school or college, but become (11) . More students will be learning at home, using computers and advanced educational software. The number of home schoolers has grown from (12) in the last two decades. Electronic networking will give more power to workers at the bottom of the (13) . Computer networks allow employees to skip over (14) and communicate directly with senior managers or even the CEO. The (15) of electronic communications will make low-status individuals (16) their points of view and offering valuable new ideas. The earth’s economy is expected to benefit hugely from (17) . Earth is a colossal system, and we will need to (18) . The space race will see many new competitors, as the United States and Russia (19) due to budget cuts. China, India, and Japan are moving ahead quickly in such fields as remote sensing satellites and (20) .

题型:单项选择题

对下列动物进行“动物绕道取食”的实验,请判断哪种动物经过尝试与错误的次数最少,就能解决绕道问题()

A.蚯蚓

B.青蛙

C.公鸡

D.小狗

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