Psychology Statistics Exam Bank 2026/2027 |
Verified Questions
Official Academic Board of Psychology | Verified Q&A | Undergraduate Psychology Students
Introduction
This document presents original practice questions covering Descriptive Statistics and Data Visualization,
Probability and Theoretical Distributions, Inferential Statistics and Hypothesis Testing, and Correlation,
Regression, and Effect Size. The items are designed to reinforce official course objectives, accurate data
interpretation, appropriate statistical test selection, and research methods reasoning for exam readiness and
academic success. These are original study questions created for mastery practice and are not disclosed course
examination items.
Content Area Overview
Content Area Questions Key Topics Weight
Mean, median, mode,
variability, frequency
Descriptive Statistics and
25 distributions, histograms, 25%
Data Visualization
boxplots, percentile
interpretation
Probability rules, normal
distribution, z scores,
Probability and
25 sampling distributions, 25%
Theoretical Distributions
standard error, Central
Limit Theorem
Null and alternative
hypotheses, p values,
Inferential Statistics and
25 alpha, Type I and Type II 25%
Hypothesis Testing
errors, t tests, ANOVA,
assumptions
Pearson r, Spearman rho,
Correlation, Regression, regression, residuals, r
25 25%
and Effect Size squared, Cohen's d, eta
squared, statistical power
Actual Questions
Domain: Descriptive Statistics and Data Visualization
1. A researcher records the quiz scores 4, 6, 8, and 10. What is the mean score?
A. 6
B. 7
C. 8
D. 9
Answer: B
Rationale: The mean is found by adding the values and dividing by the number of scores. Here, 4 + 6 + 8 + 10 =
28, and 28 divided by 4 equals 7.
Psychology Statistics Exam Bank 2026/2027
,2. A data set contains the values 2, 3, 3, 4, and 20. Which measure of central tendency best
represents the center of this skewed distribution?
A. Mean
B. Median
C. Mode
D. Range
Answer: B
Rationale: The outlier of 20 pulls the mean upward, so the median is a better indicator of center for this skewed
set.
3. Which measure of central tendency is most appropriate for nominal data such as favorite
therapy approach?
A. Mean
B. Median
C. Mode
D. Standard deviation
Answer: C
Rationale: Nominal data are categorical, so the mode is the only measure of central tendency that identifies the
most frequent category.
4. Why is a weighted mean used instead of a simple mean in some psychology courses?
A. To ignore low scores entirely
B. To give different contributions to values based on importance or credit hours
C. To remove all variability from the data
D. To convert raw scores into z scores
Answer: B
Rationale: A weighted mean is appropriate when some observations count more than others, such as exams
worth more course points than quizzes.
5. What does the range measure in a data set?
A. The middle score
B. The most common score
C. The difference between the highest and lowest scores
D. The average distance from the mean
Answer: C
Rationale: The range is the simplest measure of variability and is calculated as maximum minus minimum.
6. Which statement best describes the interquartile range?
A. It uses every score equally and is highly affected by outliers
B. It measures the spread of the middle 50 percent of scores and is resistant to extreme values
C. It is identical to the total range in every data set
D. It is used only for nominal variables
Answer: B
Rationale: The interquartile range summarizes the distance between the first and third quartiles, making it less
sensitive to outliers than the total range.
7. Two classes have the same mean exam score, but Class A has a much larger variance than Class B.
What does this indicate?
A. Class A has scores clustered more tightly around the mean
B. Class A has more spread in scores around the mean
C. Class A must also have a lower median
D. Class A has no outliers
Answer: B
Rationale: Larger variance means scores are more dispersed around the mean rather than tightly clustered.
8. Which statement best describes the standard deviation?
A. It is the number of categories in a variable
B. It is a measure of how far scores typically vary from the mean
C. It is the same as the median in normal distributions only
D. It measures only the highest score in a sample
Answer: B
Psychology Statistics Exam Bank 2026/2027
, Rationale: Standard deviation expresses the typical spread of scores around the mean in the original units of the
variable.
9. What is one key difference between sample variance and population variance formulas?
A. Sample variance divides by n minus 1, while population variance divides by n
B. Sample variance always equals zero
C. Population variance is used only for ordinal data
D. Population variance cannot be calculated numerically
Answer: A
Rationale: Sample variance uses n minus 1 to adjust for estimating population variability from a sample.
10. What is the main purpose of a frequency distribution?
A. To test a null hypothesis directly
B. To show how often each score or category occurs
C. To compute regression slopes automatically
D. To convert a sample into a population
Answer: B
Rationale: A frequency distribution organizes data by displaying how many times each value or category
appears.
11. If 15 of 60 students prefer Study Method A, what is the relative frequency for Method A?
A. 0.15
B. 0.20
C. 0.25
D. 0.40
Answer: C
Rationale: Relative frequency is the proportion of cases in a category. Here, 15 divided by 60 equals 0.25.
12. A cumulative frequency table is most useful for answering which question?
A. Which score occurs most often only at one value
B. How many cases fall at or below a given score
C. Whether a variable is nominal or interval
D. Whether the mean equals the median
Answer: B
Rationale: Cumulative frequency adds frequencies across ordered values, allowing quick identification of how
many scores fall at or below a cutoff.
13. Which graph is most appropriate for displaying the distribution of continuous test scores?
A. Histogram
B. Pie chart
C. Bar chart for categories
D. Line graph of months only
Answer: A
Rationale: Histograms are designed for continuous or interval level data and show frequencies across score
intervals.
14. A researcher wants to compare the number of participants in four therapy preference
categories. Which graph is most appropriate?
A. Histogram
B. Scatterplot
C. Bar chart
D. Boxplot
Answer: C
Rationale: Bar charts are best for categorical data because they compare frequencies across discrete categories.
15. In a standard boxplot, what does the line inside the box represent?
A. The mode
B. The median
C. The maximum score only
D. The sample size
Answer: B
Rationale: The line inside the box marks the median, while the box boundaries show the quartiles.
Psychology Statistics Exam Bank 2026/2027
Verified Questions
Official Academic Board of Psychology | Verified Q&A | Undergraduate Psychology Students
Introduction
This document presents original practice questions covering Descriptive Statistics and Data Visualization,
Probability and Theoretical Distributions, Inferential Statistics and Hypothesis Testing, and Correlation,
Regression, and Effect Size. The items are designed to reinforce official course objectives, accurate data
interpretation, appropriate statistical test selection, and research methods reasoning for exam readiness and
academic success. These are original study questions created for mastery practice and are not disclosed course
examination items.
Content Area Overview
Content Area Questions Key Topics Weight
Mean, median, mode,
variability, frequency
Descriptive Statistics and
25 distributions, histograms, 25%
Data Visualization
boxplots, percentile
interpretation
Probability rules, normal
distribution, z scores,
Probability and
25 sampling distributions, 25%
Theoretical Distributions
standard error, Central
Limit Theorem
Null and alternative
hypotheses, p values,
Inferential Statistics and
25 alpha, Type I and Type II 25%
Hypothesis Testing
errors, t tests, ANOVA,
assumptions
Pearson r, Spearman rho,
Correlation, Regression, regression, residuals, r
25 25%
and Effect Size squared, Cohen's d, eta
squared, statistical power
Actual Questions
Domain: Descriptive Statistics and Data Visualization
1. A researcher records the quiz scores 4, 6, 8, and 10. What is the mean score?
A. 6
B. 7
C. 8
D. 9
Answer: B
Rationale: The mean is found by adding the values and dividing by the number of scores. Here, 4 + 6 + 8 + 10 =
28, and 28 divided by 4 equals 7.
Psychology Statistics Exam Bank 2026/2027
,2. A data set contains the values 2, 3, 3, 4, and 20. Which measure of central tendency best
represents the center of this skewed distribution?
A. Mean
B. Median
C. Mode
D. Range
Answer: B
Rationale: The outlier of 20 pulls the mean upward, so the median is a better indicator of center for this skewed
set.
3. Which measure of central tendency is most appropriate for nominal data such as favorite
therapy approach?
A. Mean
B. Median
C. Mode
D. Standard deviation
Answer: C
Rationale: Nominal data are categorical, so the mode is the only measure of central tendency that identifies the
most frequent category.
4. Why is a weighted mean used instead of a simple mean in some psychology courses?
A. To ignore low scores entirely
B. To give different contributions to values based on importance or credit hours
C. To remove all variability from the data
D. To convert raw scores into z scores
Answer: B
Rationale: A weighted mean is appropriate when some observations count more than others, such as exams
worth more course points than quizzes.
5. What does the range measure in a data set?
A. The middle score
B. The most common score
C. The difference between the highest and lowest scores
D. The average distance from the mean
Answer: C
Rationale: The range is the simplest measure of variability and is calculated as maximum minus minimum.
6. Which statement best describes the interquartile range?
A. It uses every score equally and is highly affected by outliers
B. It measures the spread of the middle 50 percent of scores and is resistant to extreme values
C. It is identical to the total range in every data set
D. It is used only for nominal variables
Answer: B
Rationale: The interquartile range summarizes the distance between the first and third quartiles, making it less
sensitive to outliers than the total range.
7. Two classes have the same mean exam score, but Class A has a much larger variance than Class B.
What does this indicate?
A. Class A has scores clustered more tightly around the mean
B. Class A has more spread in scores around the mean
C. Class A must also have a lower median
D. Class A has no outliers
Answer: B
Rationale: Larger variance means scores are more dispersed around the mean rather than tightly clustered.
8. Which statement best describes the standard deviation?
A. It is the number of categories in a variable
B. It is a measure of how far scores typically vary from the mean
C. It is the same as the median in normal distributions only
D. It measures only the highest score in a sample
Answer: B
Psychology Statistics Exam Bank 2026/2027
, Rationale: Standard deviation expresses the typical spread of scores around the mean in the original units of the
variable.
9. What is one key difference between sample variance and population variance formulas?
A. Sample variance divides by n minus 1, while population variance divides by n
B. Sample variance always equals zero
C. Population variance is used only for ordinal data
D. Population variance cannot be calculated numerically
Answer: A
Rationale: Sample variance uses n minus 1 to adjust for estimating population variability from a sample.
10. What is the main purpose of a frequency distribution?
A. To test a null hypothesis directly
B. To show how often each score or category occurs
C. To compute regression slopes automatically
D. To convert a sample into a population
Answer: B
Rationale: A frequency distribution organizes data by displaying how many times each value or category
appears.
11. If 15 of 60 students prefer Study Method A, what is the relative frequency for Method A?
A. 0.15
B. 0.20
C. 0.25
D. 0.40
Answer: C
Rationale: Relative frequency is the proportion of cases in a category. Here, 15 divided by 60 equals 0.25.
12. A cumulative frequency table is most useful for answering which question?
A. Which score occurs most often only at one value
B. How many cases fall at or below a given score
C. Whether a variable is nominal or interval
D. Whether the mean equals the median
Answer: B
Rationale: Cumulative frequency adds frequencies across ordered values, allowing quick identification of how
many scores fall at or below a cutoff.
13. Which graph is most appropriate for displaying the distribution of continuous test scores?
A. Histogram
B. Pie chart
C. Bar chart for categories
D. Line graph of months only
Answer: A
Rationale: Histograms are designed for continuous or interval level data and show frequencies across score
intervals.
14. A researcher wants to compare the number of participants in four therapy preference
categories. Which graph is most appropriate?
A. Histogram
B. Scatterplot
C. Bar chart
D. Boxplot
Answer: C
Rationale: Bar charts are best for categorical data because they compare frequencies across discrete categories.
15. In a standard boxplot, what does the line inside the box represent?
A. The mode
B. The median
C. The maximum score only
D. The sample size
Answer: B
Rationale: The line inside the box marks the median, while the box boundaries show the quartiles.
Psychology Statistics Exam Bank 2026/2027
