STATS 2B03 Study Guide - Quiz Guide: Confidence Interval, Null Hypothesis
19 Jun 2013
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Example: 60 people write test 1 early, and 8 of them fail. Find a 98% ci for the failure rate of the class. Is margin of error in this case the margin of error was 10% - too big of a margin of error. 6. 8 determining the sample size for estimating proportions. Example: suppose that we want to estimate the proportion of canadians that are left handed accurate to within 3% with a 90% confidence interval. How large a sample should be used? when =. 10, because z. 95 is in between the two. *using the average between 1. 64 and 1. 65. Case i: can be roughly estimated from previous data. For example, from table 1, we might estimate to be take n=343. Case ii: no prior information about . Here we use the fact that (1- ) can"t be bigger than to produce the biggest possible sample size you need. So replace (1- ) by a : take n=757.
