BSTAT2 2nd Edition By Gerald Keller – Test Bank

Test Bank For BSTAT2 2nd Edition By Gerald Keller

CHAPTER 11: INFERENCE ABOUT A POPULATION

TRUE/FALSE

1. To determine the significance associated with hypothesis testing regarding the population mean μ, it is necessary to be aware of the value of the test statistic.

ANS: True, NAT: Analytic; Hypothesis Testing

2. Understanding the significance associated with hypothesis testing regarding the population mean μ requires knowledge of the test statistic.

ANS: False, NAT: Analytic; Hypothesis Testing

3. When a sample consists of 15 observations and a 95% confidence estimate for μ is needed, the correct t value is 1.753.

ANS: False, NAT: Analytic; Hypothesis Testing

4. If a sample includes 18 observations and a 90% confidence estimate for μ is necessary, the appropriate t value is 1.740.

ANS: True, NAT: Analytic; Hypothesis Testing

5. The statistic for a normally distributed sampled population follows a Student t-distribution with n degrees of freedom.

ANS: False, NAT: Analytic; Hypothesis Testing

6. Even when the sampled population is non-normal, the t-test for the population mean μ remains valid, as long as the condition is not extreme.

ANS: True, NAT: Analytic; Hypothesis Testing

7. A racing driver conducted tests on his car from 0 to 60 mph, with 20 trials resulting in an average time of 48.5 seconds and a standard deviation of 1.47 seconds. A 95% confidence interval for the 0 to 60 time is 45.2 seconds to 51.8 seconds.

ANS: False, NAT: Analytic; Hypothesis Testing

8. When creating a 95% confidence interval for a population mean from a sample size of 20, the degrees of freedom in the t-distribution is not 20.

ANS: False, NAT: Analytic; Hypothesis Testing

9. The t-distribution is utilized in constructing a confidence interval for a mean when the exact standard error is unknown.

ANS: True, NAT: Analytic; Hypothesis Testing

10. The t-distribution enables the computation of confidence intervals for means in small samples when the population variance is unidentified, irrespective of the distribution shape in the population.

ANS: False, NAT: Analytic; Hypothesis Testing

11. The t-distribution is employed to formulate a confidence interval estimate of the population mean when the population standard deviation is not known.

ANS: True, NAT: Analytic; Hypothesis Testing

12. The t-distribution assumes a normal distribution in the population.

ANS: True, NAT: Analytic; Hypothesis Testing

13. For estimating the population mean with an unknown population standard deviation and a sample size of 16, the degrees of freedom are not 8.

ANS: False, NAT: Analytic; Hypothesis Testing