C784 Applied Healthcare Statistics Midterm Exam 3 Study Guide 2026
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1. Which of the following describes the probability of an event that is certain to
occur?
A. 0.0
B. 0.5
C. 1.0
D. -1.0
Answer: C
Rationale: Probability ranges from 0 to 1, where 1 indicates an event is certain to occur.
2. In a normal distribution, what percentage of data falls within one standard
deviation of the mean?
A. 95%
B. 99.7%
C. 68%
D. 50%
Answer: C
Rationale: According to the Empirical Rule (68-95-99.7), approximately 68% of the data in
a normal distribution falls within one standard deviation of the mean.
,3. What is the primary purpose of a Null Hypothesis (H0)?
A. To state there is no effect or no difference between groups.
B. To prove the researcher’s theory is correct.
C. To predict a specific direction of the outcome.
D. To calculate the standard error of the mean.
Answer: A
Rationale: The Null Hypothesis assumes that any observed difference is due to chance and
that there is no real effect or relationship.
4. A researcher fails to reject the null hypothesis when the null hypothesis is
actually false. What type of error is this?
A. Type I Error
B. Sampling Error
C. Standard Error
D. Type II Error
Answer: D
Rationale: A Type II error occurs when you fail to reject a false null hypothesis (a ‘false
negative’).
5. Which statistical test is most appropriate for comparing the means of three or
more independent groups?
A. ANOVA
B. Chi-Square
C. T-test
D. Pearson Correlation
Answer: A
Rationale: ANOVA (Analysis of Variance) is used to determine if there are any statistically
significant differences between the means of three or more independent groups.
, 6. What does a P-value of 0.03 indicate if the significance level (alpha) is 0.05?
A. Reject the null hypothesis.
B. The results are not statistically significant.
C. Fail to reject the null hypothesis.
D. The test is invalid.
Answer: A
Rationale: When the P-value is less than the significance level (alpha), we reject the null
hypothesis as the result is statistically significant.
7. The Central Limit Theorem states that as sample size increases, the sampling
distribution of the mean approaches which shape?
A. Normal
B. Skewed Left
C. Uniform
D. Bimodal
Answer: A
Rationale: The Central Limit Theorem states that the distribution of sample means will be
approximately normal regardless of the population distribution shape, provided the
sample size is large enough.
8. Which of the following correlation coefficients indicates the strongest linear
relationship?
A. 0.75
B. -0.92
C. 0.00
D. 0.15
Answer: B
Rationale: The strength of a correlation is determined by the absolute value of the
coefficient. 0.92 is higher than 0.75, regardless of the negative sign.
|WGU
1. Which of the following describes the probability of an event that is certain to
occur?
A. 0.0
B. 0.5
C. 1.0
D. -1.0
Answer: C
Rationale: Probability ranges from 0 to 1, where 1 indicates an event is certain to occur.
2. In a normal distribution, what percentage of data falls within one standard
deviation of the mean?
A. 95%
B. 99.7%
C. 68%
D. 50%
Answer: C
Rationale: According to the Empirical Rule (68-95-99.7), approximately 68% of the data in
a normal distribution falls within one standard deviation of the mean.
,3. What is the primary purpose of a Null Hypothesis (H0)?
A. To state there is no effect or no difference between groups.
B. To prove the researcher’s theory is correct.
C. To predict a specific direction of the outcome.
D. To calculate the standard error of the mean.
Answer: A
Rationale: The Null Hypothesis assumes that any observed difference is due to chance and
that there is no real effect or relationship.
4. A researcher fails to reject the null hypothesis when the null hypothesis is
actually false. What type of error is this?
A. Type I Error
B. Sampling Error
C. Standard Error
D. Type II Error
Answer: D
Rationale: A Type II error occurs when you fail to reject a false null hypothesis (a ‘false
negative’).
5. Which statistical test is most appropriate for comparing the means of three or
more independent groups?
A. ANOVA
B. Chi-Square
C. T-test
D. Pearson Correlation
Answer: A
Rationale: ANOVA (Analysis of Variance) is used to determine if there are any statistically
significant differences between the means of three or more independent groups.
, 6. What does a P-value of 0.03 indicate if the significance level (alpha) is 0.05?
A. Reject the null hypothesis.
B. The results are not statistically significant.
C. Fail to reject the null hypothesis.
D. The test is invalid.
Answer: A
Rationale: When the P-value is less than the significance level (alpha), we reject the null
hypothesis as the result is statistically significant.
7. The Central Limit Theorem states that as sample size increases, the sampling
distribution of the mean approaches which shape?
A. Normal
B. Skewed Left
C. Uniform
D. Bimodal
Answer: A
Rationale: The Central Limit Theorem states that the distribution of sample means will be
approximately normal regardless of the population distribution shape, provided the
sample size is large enough.
8. Which of the following correlation coefficients indicates the strongest linear
relationship?
A. 0.75
B. -0.92
C. 0.00
D. 0.15
Answer: B
Rationale: The strength of a correlation is determined by the absolute value of the
coefficient. 0.92 is higher than 0.75, regardless of the negative sign.
