Question

Let p be the population proportion for the situation. (a) Find point estimates of p and q, (b) construct 90% and 95% confidence intervals for p, and (

Confidence intervals
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asked 2021-06-16
Let p be the population proportion for the situation. (a) Find point estimates of p and q, (b) construct 90% and 95% confidence intervals for p, and (c) interpret the results of part (b) and compare the widths of the confidence intervals. In a survey of 2202 U.S. adults, 1167 think antibiotics are effective against viral infections.

Answers (1)

2021-06-17
(a)\(\displaystyle\overbrace{{{p}}}={0.5300},\overbrace{{{q}}}={0.4700}\)
(b)90% confidence interval: (0.3186, 0.3516)
95% confidence interval: (0.5092, 0.5508)
(c)The 95% confidence interval is wider than the 90% confidence interval.
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