• 4
• 100% (1) 1 out of 1 people found this document helpful

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

Page 1 of 4 TUTORIAL 9 INFERENCE ABOUT COMPARING TWO POPULATIONS (CHAPTER 13) TRUE/FALSE 1. Independent samples are those for which the selection process for one is not related to the selection process for the other. ANS: T 2. In testing the difference between two population means using two independent samples, the sampling distribution of the sample mean difference is normal if the sample sizes are both greater than 30. ANS: F 3. A political analyst in Iowa surveys a random sample of registered Republicans and compares the results with those obtained from a random sample of registered Democrats. This would be an example of two independent samples. ANS: T 4. Two samples of sizes 25 and 20 are independently drawn from two normal populations, where the unknown population variances are assumed to be equal. The number of degrees of freedom of the equal-variances t -test statistic is 44. ANS: F 5. The sampling distribution of is normal if the sampled populations are normal, and approximately normal if the populations are no normal and the sample sizes n 1 and n 2 are large. ANS: T 6. Both the equal-variances and unequal variances test statistic and confidence interval estimator of require that the two populations be normally distributed. ANS: T 7. The best estimator of the difference between two population means is the difference between two sample means . ANS: T 8. When we test for differences between the means of two independent populations, we can only use a two-tailed test.

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

This is the end of the preview. Sign up to access the rest of the document.
• One '17

{[ snackBarMessage ]}

### What students are saying

• 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.

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

• 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.

Dana University of Pennsylvania ‘17, Course Hero Intern

• 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.

Jill Tulane University ‘16, Course Hero Intern