practice questions for Test3_solutions

practice questions for Test3_solutions - Solutions to...

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

Solutions to PRETEST 3. TEST 3 will be given on Wednesday December 3 I-1. We decrease the width of the confidence interval by (1) increasing sample size(2) decreasing the confidence value and (3) decreasing the standard deviation of the variable. So to increase the width of the confidence interval we would decrease sample size or increase the confidence value or increase the standard deviation. I-2. Pr (t > t 0.01 )= 0.01 = Pr(t< -t 0.01 ). I-3. This is a one sided test to the left at the 0.01 level with n large. So the rejection region is z < -z α . Here α =0.01, z 0.01 =2.33 and the rejection region is z<-2.33.(c) I-4. The probability he accepts Ho if Ho is not true β ( μ ) decreases as | μ - μ 0 | increases. Thus since |15-10| > |14-10|, β (15)< β (14)=0.5. FALSE I-5. If μ =10 then the null hypothesis is true and if the investigator rejects Ho he is WRONG. TRUE I-6. t=-2.0 then |t| = 2.0. Since 2.0<3.18 we can not reject Ho at the 0.05 level and we conclude that μ =48mm. I-7. The 95% confidence interval contains all μ we can not reject at the 0.05 level two sided. The value 88 is on the 95% confidence interval
Image of page 1

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

Image of page 2
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