NO.PZ2015120601000013
问题如下：
An analyst stated that, all else equal, increasing sample size will decrease both the standard error and the width of the confidence interval. The analyst’s statement is correct in regard to:
选项：
A. both the standard error and the confidence interval.
B. the standard error, but incorrect in regard to the confidence interval.
C. the confidence interval, but incorrect in regard to the standard error.
解释：
A is correct.
All else equal, a larger sample size will decrease both the standard error and the width of the confidence interval. In other words, the precision of the estimate of the population parameter is increased.
用哪个公示可以看出置信区间变窄了呢 置信区间与标准误的关系是什么呢
