问题
单项选择题 A1/A2型题
关于标准差，说法不正确的是（）。
A.反映全部观察值的离散程度
B.度量了一组数据偏离均数的大小
C.反映了均数代表性的好坏
D.不会小于算术均数
E.其大小与样本有关
答案
参考答案：D
解析：标准差是方差的平方根，有可能大于均数。
搜题请搜索小程序“爱下问搜题”
关于标准差，说法不正确的是（）。
A.反映全部观察值的离散程度
B.度量了一组数据偏离均数的大小
C.反映了均数代表性的好坏
D.不会小于算术均数
E.其大小与样本有关
参考答案：D
解析：标准差是方差的平方根，有可能大于均数。
完型填空（共20小题，每小题1.5分, 满分30分） A farmer went to town to sell his vegetable. But it was snowing that afternoon, and there_21_ few people in the street. So when his vegetable was sold out, it was dark. _22_ his way home, he saw a man _23_ in the snow. He put his basket _24_ and was going to _25 the man to get up. At that time he found 26 was a dead man _27_ that there was _28 blood on the ground. He was _29_ frightened that he ran away _30 , _31_ his basket away. The next _32_ the farmer was sent to the police station. After showing him the basket, an officer asked, “Is this yours?” “Yes,sir.” the farmer answered_33_. “When did you see the dead man?” “At about seven yesterday evening.” “Did you see who _34 him?” the officer brought out a knife and asked, “Have you seen it yet?” “No, sir.” The officer became angry and told the policeman _35_ him up and _36_ him in prison. That afternoon the officer went on 37_ the farmer._38 the knife, the officer asked him again, “Now, listen to me! Did you see it yet?” “Yes,sir.” “Well,” the officer became _39_ and asked, “but when and where?” “I saw it _40 this morning, sir.”
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