{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

HW 8 Solutions - 1211 would be required STATW1211.005 Prof...

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

View Full Document Right Arrow Icon
STATW1211.005 Prof. Zhang TR 02:40P-03:55P Homework 8 – Solutions Textbook: Probability and statistics for engineering and the sciences (7 th edition) by Jay L. Devore Chapter 9: Question 49 Parameter of interest: p 1 – p 2 = true difference in proportions of those responding to two different survey covers. Let p 1 = Plain, p 2 = Picture. Reject H 0 if p-value < .10 ; p-value = .4247 Fail to Reject H 0 . The data does not indicate that plain cover surveys have a lower response rate. Question 51 a. Let p 1 and p 2 denote the true incidence rates of GI problems for the olestra and control groups, respectively. We wish to test H 0 : p 1 μ 2 = 0 v. H a : p 1 p 2 ≠ 0. The pooled proportion is = .1667, from which the relevant test statistic is z = = 0.78. The two-sided P-value is 2P(Z ≥ 0.78) = .433 > α = .05, hence we fail to reject the null hypothesis. The data do not suggest a statistically significant difference between the incidence rates of GI problems between the two groups. b. , so a common sample size of m = n =
Image of page 1

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

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1211 would be required. STATW1211.005 Prof. Zhang TR 02:40P-03:55P Chapter 12: Question 11 a. expected change for a one degree increase = -.01, and is the expected change for a 10 degree increase. b. , and . c. The probability that the first observation is between 2.4 and 2.6 is . The probability that any particular one of the other four observations is between 2.4 and 2.6 is also .8164, so the probability that all five are between 2.4 and 2.6 is . d. Let Y 1 and Y 2 denote the times at the higher and lower temperatures, respectively. Then Y 1 - Y 2 has expected value . The standard deviation of Y 1 - Y 2 is . Thus . Question 19 N = 14, , , , , a. , , so we use the equation . b. c. Estimated expected change d. No, the value 500 is outside the range of x values for which observations were available (the danger of extrapolation). Question 23 a. Using the given y i ’s and the formula , . The computation formula gives b. so ....
View Full Document

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern