hw - Stat 401G: Quiz 1 Homework Solutions For Friday...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon

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

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Stat 401G: Quiz 1 Homework Solutions For Friday September 9, 2011 Problem 1.43 Part A : E (¯ y ) = μ = 0 . 10 and V ar (¯ y ) = σ 2 n = . 01 50 = 0 . 002 . We are usually interested in SD (¯ y ) = σ √ n = . 1 √ 50 ≈ . 01414 . In terminology used in class, E (¯ y ) and V ar (¯ y ) are respectively the mean and variance of the sampling distribution of ¯ y. Part B : For a reasonably large sample size, the central limit theorem says that the sampling distribution of ¯ y should be approximately normally distributed even though the population from which the sample is drawn is not normal. I might use the notations ¯ y . ∼ N μ, σ √ n to say that ¯ y is approximately normally distributed. Part C : z = . 13- . 1 . 01414 = 2 . 12. P ( ¯ Y > . 13 ) = P ( Z > 2 . 12) = 0 . 5- . 4830 = 0 . 0170 Problem 1.45 Part A : You will use the formula ¯ y ± t . 01 / 2 s √ n where the t value is based on n- 1 = 71 degrees of freedom. This number of degrees of freedom is not on your table. In lab, we will show you how to use the computer to get this value which is 2table....
View Full Document

This note was uploaded on 02/06/2012 for the course STAT 401 taught by Professor Shelley during the Spring '08 term at Iowa State.

Page1 / 2

hw - Stat 401G: Quiz 1 Homework Solutions For Friday...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online