题目
An increase in sample size is most likely to result in a:
选项
A.wider confidence interval.
B.decrease in the standard error of the sample mean.
C.lower likelihood of sampling from more than one population.
答案
B
解析
： B is correct. All else being equal, as the sample size increases, the standard error of the sample mean decreases and the width of the confidence interval also decreases. ： B正确。 在其他条件相同的情况下，随着样本量的增大，样本均值的标准误差减小，置信区间的宽度也减小。