Biology 2244A/B Lecture Notes - Lecture 9: Confidence Interval, Binomial Distribution, Statistical Parameter
Document Summary
Normal as approximation to binomial distribution probablities. Requirements: srs, conditions for binomial distribution satisfied, np>=5, nq>=5. Notation for proportions: p = probability in entire population, p-hat = sample proportion of x successes in sample size n, q-hat = sample proportion of failures. Point estimate: single value used to approximate population parameter. Range of values used to estimate true value of population parameter. Confidence level = 1 alpha (alpha is significance level: called degree of confidence, proportion of times confidence interval contain population parameter. Notation: z(a/2) is positive z-value that separate area of a/2 in right tail of standard normal distribution. Divided in left tail and right tail is 0. 025. From the left side of the graph, probability is 0. 9750. When data from srs used to estimate population proportion. E (margin of error) maximum difference between observed sample proportion p-hat and true population proportion p.