STA 309 Study Guide - Midterm Guide: Standard Deviation, Test Statistic, Snack
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What sample size is needed if you want to be x% confident that the estimate is within . 02 of the true population? if p-hat is not given, use 0. 5. > p. hat = 0. 5 # or whatever you are given. > conf. level = 0. 95 # or whatever you are given. > n = ceiling((z. star / margin. of. error)^2 * (p. hat p. hat^2)) The true proportion of students who study abroad is. A researcher selects a random sample of 40 students and records if they have studied abroad. What is the probability that the proportion of students in the sample who have studied abroad is less than. >pbinom(9,40,. 3) gives the exact value: ut would like to determine the % of ut students who consume more than two cups of coffee per day. The required sample size is- (z*/m)^2*p*(1-p) z* is 1. 96, or qnorm(. 975), m is 0. 04, and we let p = 0. 5 to make sure that the sample size is adequate.
