lecture11

lecture11 - Sample mean in general Theorem 6.1 (in the...

This preview shows pages 1–3. Sign up to view the full content.

Sample mean in general * Theorem 6.1 (in the book): If a random sample of n observations is selected from a population with a normal distribution (nor- mal population), the sampling distribution of ¯ x will be a normal distribution. Theorem 6.2 (Central Limit Theorem): Con- sider a random sample of n observations selected from a population ( any popula- tion) with mean μ and standard deviation σ . Then, when n is suﬃciently large, the sampling distribution of ¯ x will be approx- imately a normal distribution with mean μ ¯ x = μ and standard deviation σ ¯ x = σ/ n . The larger the sample size, the better will be the normal approximation to the sam- pling distribution of ¯ x . n = 30 is usually good enough. * February 23, 2010 1

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Sample test problem Problem: Suppose we have selected a ran- dom sample of n = 36 observations from a population with mean equal to 80 and standard deviation equal to 6. It is known that the population is not extremely skewed. a.
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 06/06/2011 for the course STAT 515 taught by Professor Zhao during the Spring '10 term at South Carolina.

Page1 / 8

lecture11 - Sample mean in general Theorem 6.1 (in the...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online