单选题
Which of the following characterizes the typical construction of a confidence interval correctly? A. Point estimate ± (Standard error/Reliability factor). B. Point estimate ± ( Reliability factor × Standard error). C. ( Reliability factor × Standard error) ± Point estimate.
【正确答案】
B
【答案解析】We can construct a confidence interval by adding and subtracting some amount from the point estimate. In general, confidence intervals have the following form.
Point estimate + Reliability factor x Standard error
Point estimate = the value of a sample statistic of the population parameter
Reliability factor = a number that depends on the sampling distribution of the point estimate and the probability the point estimate falls in the confidence interval (1-α)
Standard error = the standard error of the point estimate