Quiz 1
Question 1. 1. The sample proportion is the best point estimate of the population proportion. (Points : 5)
True
False
Question 2. 2. A researcher collected 15 data points that seem to be reasonably bell shaped. Which distribution should the researcher use to calculate confidence intervals? (Points : 5)
A t-distribution with 14 degrees of freedom
A t-distribution with 15 degrees of freedom
A general normal distribution
A nonparametric method
Question 3. 3. A point estimate is the value of a ____________ that estimates the value of a ______________. (Points : 5)
Parameter; statistic
Statistic; parameter
Random variable; statistic
Random variable; parameter
Question 4. 4. The _______________ hypothesis contains the "=" sign. (Points : 5)
Alternative
Conditional
Explanatory
Null
Question 5. 5. As the level of confidence increases the margin of error decreases. (Points : 5)
True
False
Question 6. 6. The margin of error of a confidence interval of a parameter depends on all but which of the following? (Points : 5)
The level of confidence
The sample mean
The sample size
The standard deviation of the population
Question 7. 7. If we reject the null hypothesis when the null hypothesis is true, then we have made a (Points : 5)
Correct decision
Type I error
Type II error
Type alpha error
Question 8. 8. A confidence interval for a parameter is (Points : 5)
A point estimate plus a margin of error
An interval of numbers combined with the likelihood the interval contains the unknown parameter
A statement of believability of a statistical result
An interval of probabilities concerning a parameter
Question 9. 9. If the sample mean is 9, which of these could reasonably be a confidence interval for the population mean? (Points : 5)
(12, 15)
(3, 6)
(7, 11)
None of the above
Question 10. 10. The best point estimate for the standard deviation of a population is (Points : 5)
The standard deviation of the sample
The variance of the sample
n-1
The variance of the population
Question 11. 11. In a one-tailed test of the hypothesis using the classical method, the critical region is the area under the graph located (Points : 5)
Only at the critical value
In the tail
Between the critical value and the mean
Below the mean on the side of the graph opposite the critical value
Question 12. 12. The mean age of professors at a university is 55.3 years. If a hypothesis test is performed, how should you interpret a decision that fails to reject the null hypothesis? (Points : 5)
There is not sufficient evidence to reject the claim mu is 55.3
There is sufficient evidence to reject the claim mu is 55.3
There is not sufficient evidence to support the claim mu is 55.3
There is sufficient evidence to support the claim mu is 55.3
Question 13. 13. Type I and Type II errors are independent events. (Points : 5)
True
False
Question 14. 14. A professor wishes to compute a confidence interval for the average percentage grade in the class. Which population parameter is being studied? (Points : 5)
The population mean
The population proportion
The population variance
The degrees of freedom
Question 15. 15. A study is trying to determine what percentage of students drive SUVs. The population parameter to be estimated is (Points : 5)
The sample mean
The population proportion
The standard error of the sample mean
The sample size required
Question 1. 1. The sample proportion is the best point estimate of the population proportion. (Points : 5)
True
False
Question 2. 2. A researcher collected 15 data points that seem to be reasonably bell shaped. Which distribution should the researcher use to calculate confidence intervals? (Points : 5)
A t-distribution with 14 degrees of freedom
A t-distribution with 15 degrees of freedom
A general normal distribution
A nonparametric method
Question 3. 3. A point estimate is the value of a ____________ that estimates the value of a ______________. (Points : 5)
Parameter; statistic
Statistic; parameter
Random variable; statistic
Random variable; parameter
Question 4. 4. The _______________ hypothesis contains the "=" sign. (Points : 5)
Alternative
Conditional
Explanatory
Null
Question 5. 5. As the level of confidence increases the margin of error decreases. (Points : 5)
True
False
Question 6. 6. The margin of error of a confidence interval of a parameter depends on all but which of the following? (Points : 5)
The level of confidence
The sample mean
The sample size
The standard deviation of the population
Question 7. 7. If we reject the null hypothesis when the null hypothesis is true, then we have made a (Points : 5)
Correct decision
Type I error
Type II error
Type alpha error
Question 8. 8. A confidence interval for a parameter is (Points : 5)
A point estimate plus a margin of error
An interval of numbers combined with the likelihood the interval contains the unknown parameter
A statement of believability of a statistical result
An interval of probabilities concerning a parameter
Question 9. 9. If the sample mean is 9, which of these could reasonably be a confidence interval for the population mean? (Points : 5)
(12, 15)
(3, 6)
(7, 11)
None of the above
Question 10. 10. The best point estimate for the standard deviation of a population is (Points : 5)
The standard deviation of the sample
The variance of the sample
n-1
The variance of the population
Question 11. 11. In a one-tailed test of the hypothesis using the classical method, the critical region is the area under the graph located (Points : 5)
Only at the critical value
In the tail
Between the critical value and the mean
Below the mean on the side of the graph opposite the critical value
Question 12. 12. The mean age of professors at a university is 55.3 years. If a hypothesis test is performed, how should you interpret a decision that fails to reject the null hypothesis? (Points : 5)
There is not sufficient evidence to reject the claim mu is 55.3
There is sufficient evidence to reject the claim mu is 55.3
There is not sufficient evidence to support the claim mu is 55.3
There is sufficient evidence to support the claim mu is 55.3
Question 13. 13. Type I and Type II errors are independent events. (Points : 5)
True
False
Question 14. 14. A professor wishes to compute a confidence interval for the average percentage grade in the class. Which population parameter is being studied? (Points : 5)
The population mean
The population proportion
The population variance
The degrees of freedom
Question 15. 15. A study is trying to determine what percentage of students drive SUVs. The population parameter to be estimated is (Points : 5)
The sample mean
The population proportion
The standard error of the sample mean
The sample size required
