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During archery practice one day, Sadie asked a friend to take a picture of the target after she shot each arrow. After practice, they measured the distance from the bull's-eye (in centimeters) in 100100 randomly selected pictures. They found a 99%99\% confidence interval of for the mean distance from the bull's eye for the arrows Sadie shot that day.\newlineIs the following conclusion valid?\newlineIf 100100 more samples are taken (with elements chosen randomly and independently), it is expected that exactly 9999 of them will each produce a 99%99\% confidence interval that contains its sample mean.\newlineChoices:\newline(A)yes\newline(B)no

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Q. During archery practice one day, Sadie asked a friend to take a picture of the target after she shot each arrow. After practice, they measured the distance from the bull's-eye (in centimeters) in 100100 randomly selected pictures. They found a 99%99\% confidence interval of for the mean distance from the bull's eye for the arrows Sadie shot that day.\newlineIs the following conclusion valid?\newlineIf 100100 more samples are taken (with elements chosen randomly and independently), it is expected that exactly 9999 of them will each produce a 99%99\% confidence interval that contains its sample mean.\newlineChoices:\newline(A)yes\newline(B)no
  1. Confidence Interval Definition: A 99%99\% confidence interval means that we can be 99%99\% confident that the true population mean lies within the interval, not that 9999 out of 100100 samples will contain the sample mean within their own confidence intervals.
  2. Common Misunderstanding: The statement is a common misunderstanding of confidence intervals. The correct interpretation is that if we were to take many samples and build a confidence interval from each, 99%99\% of those intervals would contain the true population mean, not necessarily the sample mean.
  3. Correct Interpretation: Therefore, the conclusion that exactly 9999 of the 100100 new samples will produce a 99%99\% confidence interval containing its sample mean is incorrect.

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