FINAL STUDY GUIDE 2026 SOLVED ITEMS
PREMIUM REVIEW
◉ Estimator. Answer: formula or rule used to estimate a population
parameter
◉ Estimate. Answer: the actual numerical value calculated from the
sample
◉ Standard error (SE). Answer: the standard deviation of the
estimator; measures how much the estimator varies across samples
◉ Unbiased estimator. Answer: an estimator whose expected value
equals the true population parameter
◉ Confidence interval (CI). Answer: an interval of values likely to
contain the true parameter
◉ Level of confidence. Answer: the probability that the interval
contains the true parameter (commonly 0.90, 0.95, 0.99)
◉ Population mean (mu). Answer: the true mean of the population