WGU C207 DATA-DRIVEN DECISION-
MAKING COMPREHENSIVE EXAM
QUESTIONS AND ANSWERS
1. A researcher is measuring the weight of various packages in kilograms. Which level of
measurement does this data represent?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
Answer: D
Conceptual Explanation: Weight has a true zero point and consistent intervals between
units, making it ratio-level data.
2. In a normal distribution, what percentage of data falls within two standard deviations of
the mean?
A. 68%
B. 99.7%
,C. 95%
D. 50%
Answer: C
Conceptual Explanation: According to the Empirical Rule, approximately 95% of data falls
within two standard deviations of the mean in a normal distribution.
3. Which of the following occurs when a researcher fails to reject a null hypothesis that is
actually false?
A. Type II Error
B. Type I Error
C. Confidence Interval Error
D. Standard Error
Answer: A
Conceptual Explanation: A Type II error (false negative) occurs when the null hypothesis
is not rejected despite being false.
4. What is the primary purpose of a P-value in hypothesis testing?
A. To measure the probability of observing the results if the null hypothesis is true.
B. To determine the probability that the null hypothesis is true.
C. To prove the alternative hypothesis is true.
, D. To calculate the exact mean of the population.
Answer: A
Conceptual Explanation: The P-value represents the probability of obtaining test results
at least as extreme as the results actually observed, under the assumption that the null
hypothesis is correct.
5. In a simple linear regression model, what does the R-squared value represent?
A. The slope of the regression line.
B. The correlation coefficient between X and Y.
C. The average error of the prediction.
D. The proportion of variance in the dependent variable explained by the independent
variable.
Answer: D
Conceptual Explanation: R-squared, or the coefficient of determination, measures how
well the statistical model predicts the outcome by calculating the shared variance.
6. Which sampling method involves dividing the population into groups and then randomly
selecting individuals from every group?
A. Cluster Sampling
B. Convenience Sampling
C. Stratified Random Sampling
MAKING COMPREHENSIVE EXAM
QUESTIONS AND ANSWERS
1. A researcher is measuring the weight of various packages in kilograms. Which level of
measurement does this data represent?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
Answer: D
Conceptual Explanation: Weight has a true zero point and consistent intervals between
units, making it ratio-level data.
2. In a normal distribution, what percentage of data falls within two standard deviations of
the mean?
A. 68%
B. 99.7%
,C. 95%
D. 50%
Answer: C
Conceptual Explanation: According to the Empirical Rule, approximately 95% of data falls
within two standard deviations of the mean in a normal distribution.
3. Which of the following occurs when a researcher fails to reject a null hypothesis that is
actually false?
A. Type II Error
B. Type I Error
C. Confidence Interval Error
D. Standard Error
Answer: A
Conceptual Explanation: A Type II error (false negative) occurs when the null hypothesis
is not rejected despite being false.
4. What is the primary purpose of a P-value in hypothesis testing?
A. To measure the probability of observing the results if the null hypothesis is true.
B. To determine the probability that the null hypothesis is true.
C. To prove the alternative hypothesis is true.
, D. To calculate the exact mean of the population.
Answer: A
Conceptual Explanation: The P-value represents the probability of obtaining test results
at least as extreme as the results actually observed, under the assumption that the null
hypothesis is correct.
5. In a simple linear regression model, what does the R-squared value represent?
A. The slope of the regression line.
B. The correlation coefficient between X and Y.
C. The average error of the prediction.
D. The proportion of variance in the dependent variable explained by the independent
variable.
Answer: D
Conceptual Explanation: R-squared, or the coefficient of determination, measures how
well the statistical model predicts the outcome by calculating the shared variance.
6. Which sampling method involves dividing the population into groups and then randomly
selecting individuals from every group?
A. Cluster Sampling
B. Convenience Sampling
C. Stratified Random Sampling
