Homework 6, Econ 400

Homework 6, Econ 400 - Homework Assignment # 6 Exercise...

Info iconThis preview shows pages 1–3. 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: Homework Assignment # 6 Exercise Title: Homework No. 6 Date: 5/12/2009 Name (Last, First): Answer Key PID: Section No. of Course: Sections 1 & 2 Sign the Honor Pledge: 6.18 a) 0458 . 100 ) 7 (. 3 . ; 3 . ˆ ˆ = = = = = n pq p p p σ μ b) 015 . 400 ) 9 (. 1 . ; 1 . ˆ ˆ = = = = = n pq p p p σ μ c) 0310 . 250 ) 4 (. 6 . ; 6 . ˆ ˆ = = = = = n pq p p p σ μ 6.19 a) Since the sample sizes are very large, the sampling distributions in Exercise 6.18 will each be approximately normal, with appropriate means and variances. The interval p p ˆ 2 σ ± should cover 95% of the measurements. 6.21 For n = 1000 and p = .1, the sample proportion p ˆ is approximately normally distributed with 0095 . 1000 ) 9 (. 1 . ; 1 . ˆ ˆ = = = = = n pq p p p σ μ a) [ ] [ ] 0174 . 4826 . 5 . 11 . 2 0095 . 1 . 12 . 12 . ˆ =- = = - = < z P z P p P b) [ ] [ ] 5 . 0095 . 1 . 10 . 10 . ˆ = < = - = < z P z P p P c) [ ] [ ] 9652 . ) 4826 (. 2 11 . 2 11 . 2 02 . ) ˆ ( 02 . = = ≤ ≤- = ≤- ≤- z P p p P 6.22 The values n pq p / ˆ = σ for n = 100 and various values of p are tabulated and graphed below. Notice that p ˆ σ is maximum for p = .5 and becomes very small for p near 0 and 1. p .01 .10 .30 .50 .70 .90 .99 p ˆ σ .0099 .03 .0458 .05 .0458 .03 .0099 SE p .1 .2 .3 .4 .5 .6 .7 .8 .9 1 .01 .02 .03 .04 .05 6.23 Fir fixed p , n pq p / ˆ = σ . If n is increased, p ˆ σ decreases. Similarly, since n x σ σ = ˆ , the standard deviation of x will decrease as n increases....
View Full Document

This note was uploaded on 04/14/2008 for the course ECON 400 taught by Professor Turchi during the Spring '08 term at UNC.

Page1 / 5

Homework 6, Econ 400 - Homework Assignment # 6 Exercise...

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

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