已知总体标准差,但样本含量不大,总体均数95%的可信区间用
- A.<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0.gif'>-t0.025(V)S<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_1.gif'>,<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_2.gif'>+t0.025(V)S<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_3.gif'>
- B.<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_4.gif'>-1.96S<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_5.gif'>,<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_6.gif'>+1.96S<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_7.gif'>
- C.<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_8.gif'>-1.96σ<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_9.gif'>,<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_10.gif'>+1,96σ<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_11.gif'>
- D.<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_12.gif'>-1.645S<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_13.gif'>,<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_14.gif'>+1.645S<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_15.gif'>
- E.<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_16.gif'>-2.58S<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_17.gif'>,<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_18.gif'>+2.58S<img border='0' alt='' src='http://tp.mxqe.com/data/92/12259723_0_19.gif'>
正确答案及解析
正确答案
D
解析
总体均数的可信区间估计计算方法有3种:①σ未知且n较小:按t分布的原理用此式计算可信区间:(-
)。②σ未知但n足够大:这时t分布近似服从标准正态分布,上式可简化成式:(
)。③σ已知,按正态分布原理用下式计算可信区间:(
)。本题应选用最后一种方法计算,故本题选D。
包含此试题的试卷
你可能感兴趣的试题
参与一碳单位代谢的维生素是
-
- A.维生素B<img border='0' alt='' src='http://tp.mxqe.com/data/6/12850360_0.gif'>
- B.维生素B<img border='0' alt='' src='http://tp.mxqe.com/data/6/12850360_0_1.gif'>
- C.维生素PP
- D.叶酸
- E.泛酸
- 查看答案
转氨酶的辅酶是
-
- A.磷酸吡哆醛
- B.焦磷酸硫胺素
- C.生物素
- D.四氢叶酸
- E.泛酸
- 查看答案
紫外线对DNA的损伤主要是引起
-
- A.碱基缺失
- B.碱基插入
- C.碱基置换
- D.嘧啶二聚体形成
- E.磷酸二酯键断裂
- 查看答案
参与氧化脱氨的维生素是
-
- A.维生素B<img border='0' alt='' src='http://tp.mxqe.com/data/93/12278520_0.gif'>
- B.维生素B<img border='0' alt='' src='http://tp.mxqe.com/data/93/12278520_0_1.gif'>
- C.维生素PP
- D.叶酸
- E.泛酸
- 查看答案
参与转氨基的维生素是
-
- A.维生素B<img border='0' alt='' src='http://tp.mxqe.com/data/93/12278521_0.gif'>
- B.维生素B<img border='0' alt='' src='http://tp.mxqe.com/data/93/12278521_0_1.gif'>
- C.维生素PP
- D.叶酸
- E.泛酸
- 查看答案