**Unformatted text preview: **X i is the binge drinking percent-age at i-th campus which is distributed normally with mean 40 and standard deviation of 14 , i.e. X i ∼ N (40 , 14 2 ) . Since binge drinking percent-ages in different campuses should be indepen-dent, X i ’s should be assumed to be independent random variables. 4. X 1 , ··· ,X n form a random sample if X i are independent and identically distributed random variables. A statistic is a random variable. Hence sample mean ¯ X = ∑ n i =1 X i /n is a statistic. It will be distributed as ¯ X ∼ N (40 / 140 , 14 2 / 140) . Note. Read section 5.4, 5.5 and do Ex.5.48. 5.52. 5.63. Lecture 2-4 will be based on sections 6.1-6.2....

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- Fall '04
- Chung
- Statistics, Standard Deviation, Probability theory, Drinking culture, Binge drinking, Moo K. Chung