Suppose you want to estimate the true proportion of U.S. women with a gluten sensitivity. In a large study using a random sample of 2500 U.S. women, 163 women, 163 women had a gluten sensitivity.
1. Calculate a 98% confidence interval for the true proportion of women with a gluten-sensitivity. As in the last assignment, show all the steps.
2. Interpret the confidence LEVEL.
3. How many women need to be examined in order to estimate the true proportion to within 0.5% (0.005) with the same level of confidence. Show the calculations.
1. z value for 98% CI is 2.326 as P(-2.326<z<2.326)=0.98
Now
So Margin of the Error is
Hence CI is
Population proportion will lie in the range of 0.054 to 0.076 with 98% CI
Now for E=0.005
So
Suppose you want to estimate the true proportion of U.S. women with a gluten sensitivity. In...
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