摇一摇 · 2023年08月06日
NO.PZ2022123001000122
问题如下：
An analyst collects the following data related to paired observations for Sample A and Sample B. Assume that both samples are drawn from normally distributed populations and that the population variances are not known.
The t-statistic to test the hypothesis that the mean difference is equal to zero is closest to:
选项：
A.0.23
B.0.27
C.0.52
解释：
这道题可以用计算器按吗？
星星_品职助教 · 2023年08月08日
同学你好，
可以，先手动算出Sample A 和 Sample B的差，然后把这列差输入计算器即可。
1）将红框中的差值逐个输入计算器的2nd+7；
2）2nd+8得到均值 1.4， 和样本标准差 6.0663
3）求得均值的标准误为 样本标准差除以根号n= 6.0663/ 根号5 =2.7129
4）代入下方公式
由于本题是检验是否为0，所以公式简化为：
代入刚刚求得的均值和标准误，得到结果：1.4 / 2.7129=0.5160
Lily0923 · 2023年08月19日
为什么求标准误的时候 分母是÷n 而不是n-1呢？为什么是除以5而不是4？
NO.PZ2022123001000122 问题如下 analyst collects the following ta relatetopaireobservations for Sample A anSample Assume thboth samples areawn from normally stributepopulations anththe population variancesare not known.The t-statistic to test the hypothesis ththe mefferenis equto zero is closest to: A.0.23 B.0.27 C.0.52 2n8得到均值 1.4， 和样本标准差 6.0663这里用计算器会按，但是没明白为什么要用Sx 而不是σx？
NO.PZ2022123001000122 问题如下 analyst collects the following ta relatetopaireobservations for Sample A anSample Assume thboth samples areawn from normally stributepopulations anththe population variancesare not known.The t-statistic to test the hypothesis ththe mefferenis equto zero is closest to: A.0.23 B.0.27 C.0.52 看题目是满足这些条件的，为啥不是用这个公式啊？为啥答案是除以根号5而不是除以（s/根号5）？
NO.PZ2022123001000122问题如下 analyst collects the following ta relatetopaireobservations for Sample A anSample Assume thboth samples areawn from normally stributepopulations anththe population variancesare not known.The t-statistic to test the hypothesis ththe mefferenis equto zero is closest to: A.0.23B.0.27C.0.52 你好 本题第二步骤的标准差在计算器上如何按的
NO.PZ2022123001000122 问题如下 analyst collects the following ta relatetopaireobservations for Sample A anSample Assume thboth samples areawn from normally stributepopulations anththe population variancesare not known.The t-statistic to test the hypothesis ththe mefferenis equto zero is closest to: A.0.23 B.0.27 C.0.52
