（before impact 的样本数为3888）

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（before impact 的样本数为3888）
Which of the following is not an acceptable interpretationof the 95% confidence interval for the mean number of animals using the survey area per hour before impact?
Select one:
a.With 95% confidence we estimate the mean mean number of animals using the survey area per hour before impact to be somewhere in the confidence interval.
b.If many samples of size 3,887 from the total population of animals using the survey area per hour before impact,and confidence intervals for the mean for each of thesesamples were calculated in the same manner as the confidence interval above was calculated,then 95% of these confidence intervals would contain the true value of the population mean.
c.95% of the time the mean number of animals using the survey area per hour before impact is somewhere in the confidence interval.

A和C基本意思一样,都正确.
B不对,其含义是,根据多个样本计算总体均值的多个置信区间,那么众多区间中95%的区间会涵盖总体均值.其错误的理由是,单个随机样本计算的置信区间有95%的可能性涵盖总体均值,并不意味着多个区间中有95%的区间会涵盖总体均值.

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