{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

section8_4_solutions - Name 1 Time to respond for 911 calls...

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

View Full Document Right Arrow Icon
Name: 1) Time to respond for 911 calls was measured for 75 calls in two cities, C 1 and C 2. The results of the study were: Measure C1 C2 Sample size 75 75 Sample mean 5.4 6.1 Sample variance 1.57 2.54 This problem is solved exactly like Example 8.3 in the text. a) Estimate the difference in the mean response time for the two cities. The point estimate of μ 1 - μ 2 is y 1 - y 2 = 5 . 4 - 6 . 1 = - 0 . 7 b) Find a bound for the error of estimation. See Example 8.3 in the text. The standard deviation of the estimated difference is: σ Y 1 - Y 2 = radicalBigg σ 2 1 n 1 + σ 2 2 n 2 radicalBigg s 2 1 n 1 + s 2 2 n 2 = radicalbigg 1 . 57 75 + 2 . 54 75 = 0 . 234 The probability that the error of estimation is less than σ Y 1 - Y 2 2(0 . 234) = 0 . 468 is . 95. (two standard deviations) 2) An exit poll of 1 , 000 voters finds that 530 supported a certain candidate. a) Estimate the proportion of the voting population that supports the candidate. The estimator is ˆ p = y n = 530 1000 = 0 . 530 b) Find a bound for the error of estimation. The standard error for the estimator ˆ p is given by: σ ˆ p = radicalbigg pq n radicalbigg ˆ p (1 - ˆ p ) n = radicalbigg 0 . 53 · 0 . 47 1000 = 0 . 0158 With probability . 95, the error of estimation is less than 2 σ ˆ p = 0 . 0316
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
3) Suppose Y is a single observation from an exponential distribution with unknown mean θ .
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the 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