In: Statistics and Probability
A researcher wishes to estimate the proportion of adults who have high-speed internet access. What size sample should be obtained if she wishes the estimate to be within 0.04 with 99% confidence if
a) she uses a previous estimate of 0.36?
b) she does not use any prior estimates?
At 99 % confidence level the Z score is 2.58 if the distribution is normal
a) If the prior estimate is 0.36 then the minimum samople is calculated as
b) if prior estimate is not available the sample proportion is assumed as 0.50
The Z score is computed by Z table shown below