Concept explainers
The Berkman Center Study referenced in Example 8.13 talked to teens In smaller focus groups, but also Interviewed additional teens over the phone. When the study was complete, 588 teens had answered the question about their Facebook friends wIth 159 savIng that the have more than 500 frIends. Use the “plus-four” method to find a 90% confidence Interval for the true proportion of teens that would report having more than 500 Facebook friends based on this larger sample. Compare the results to those in Example 8.13.
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Introductory Statistics
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Calculus Volume 1
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Elementary Statistics: Picturing the World (7th Edition)
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