This preview shows pages 1–4. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: STATISTICAL INFERENCE: REVIEW MULTIPLE CHOICE QUESTIONS In the following multiplechoice questions, please circle the correct answer. 1. In testing the difference between two population means, for which the population variances are unknown and assumed to be equal, two independent samples are drawn from the populations. Which of the following tests is appropriate? a. ztest b. Equalvariances ttest c. Ftest d. Matched pairs ttest ANSWER: b 2. When the necessary conditions are met, a twotail test is being conducted to test the difference between two population proportions. If the value of the test statistic z is 1.86, then the pvalue is: a. 0.4686 b. 0.0314 c. 0.0628 d. 0.0942 ANSWER: c 3. A random sample of 20 observations taken from a normally distributed population revealed a sample mean of 65 and a sample variance of 16. The lower limit of a 90% confidence interval for the population mean would equal: a. 66.546 b. 63.454 c. 63.812 d. 66.188 ANSWER: b Statistical Inference: Review 4. In testing for the equality of two population variances, when the populations are normally distributed, the 5% level of significance has been used. To determine the rejection region, it will be necessary to refer to the F table corresponding to an uppertail area of: a. 0.950 b. 0.050 c. 0.025 d. 0.100 ANSWER: c 5. When the necessary conditions are met, a twotail test is being conducted to test the difference between two population proportions. The two sample proportions are 1 0.20 p = and 2 0.15 p = , and the standard error of the sampling distribution of 2 1 p p is 0.25. The calculated value of the test statistic will be: a. z = 2.0 b. z = 1.15 c. t = 2.0 d. t = 1.2 ANSWER: a 6. A random sample of size 15 taken from a normally distributed population resulted in a sample variance of 25. The upper limit of a 99% confidence interval for the population variance would be: a. 12.868 b. 92.032 c. 85.896 d. 75.100 ANSWER: c 7. In testing the null hypothesis : 2 1 = p p H , if H is true, the test could lead to: a. a Type I error b. a Type II error c. either a Type I or a Type II error d. none of the above ANSWER: a 8. A sample of size 200 from population 1 has 50 successes. A sample of size 200 from population 2 has 40 successes. The value of the test statistic for testing the null hypothesis that the proportion of successes in population 1 exceeds the proportion of successes in population 2 by 0.025 is: a. 1.96 b. 1.25 Statistical Inference: Review c. 0.5998 d. 1.20 ANSWER: c 9. A sample of size 400 had 60 successes. The upper limit of a 90% confidence interval for the A sample of size 400 had 60 successes....
View
Full
Document
 Fall '10
 huang

Click to edit the document details