Research Methods in Psychology Exam 2026 | Statistical
Concepts Practice Test
1. What is the primary purpose of descriptive statistics in psychological research?
A. To determine cause-and-effect relationships
B. To summarize and organize data
C. To manipulate variables
D. To eliminate bias
Correct Answer: B. To summarize and organize data
Explanation:
Descriptive statistics help researchers organize, summarize, and present data in a meaningful
way through measures such as mean, median, mode, and standard deviation.
2. Which measure of central tendency is most affected by extreme scores?
A. Median
B. Mode
C. Mean
D. Range
Correct Answer: C. Mean
Explanation:
The mean includes all scores in its calculation, making it sensitive to unusually high or low
values known as outliers.
3. A researcher reports the middle score in a distribution. Which measure is being used?
A. Mean
B. Median
C. Mode
D. Variance
Correct Answer: B. Median
Explanation:
,The median represents the midpoint of an ordered dataset where half the scores fall above
and half below.
4. Which statistical measure indicates the most frequently occurring score?
A. Mean
B. Median
C. Standard deviation
D. Mode
Correct Answer: D. Mode
Explanation:
The mode identifies the value or score that appears most often in a dataset.
5. What does a large standard deviation indicate?
A. Scores are closely clustered around the mean
B. Scores are widely spread out
C. There are no outliers
D. The distribution is normal
Correct Answer: B. Scores are widely spread out
Explanation:
A large standard deviation reflects greater variability among scores, meaning data points are
spread farther from the mean.
6. Which type of variable is measured in categories without numerical meaning?
A. Interval
B. Ratio
C. Nominal
D. Continuous
Correct Answer: C. Nominal
Explanation:
Nominal variables classify data into categories such as gender or eye color without
numerical ranking or order.
7. In a positively skewed distribution, the tail extends toward:
, A. Lower scores
B. Higher scores
C. The center
D. Both directions equally
Correct Answer: B. Higher scores
Explanation:
A positive skew has a long tail stretching toward higher numerical values due to extreme
high scores.
8. Which level of measurement includes a true zero point?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
Correct Answer: D. Ratio
Explanation:
Ratio scales contain equal intervals and a meaningful zero, allowing statements like “twice as
much.”
9. What is the range in statistics?
A. Average score
B. Difference between highest and lowest scores
C. Most frequent score
D. Square root of variance
Correct Answer: B. Difference between highest and lowest scores
Explanation:
Range is a simple measure of variability calculated by subtracting the smallest value from
the largest.
10. A bell-shaped curve represents which distribution?
A. Bimodal distribution
B. Positively skewed distribution
Concepts Practice Test
1. What is the primary purpose of descriptive statistics in psychological research?
A. To determine cause-and-effect relationships
B. To summarize and organize data
C. To manipulate variables
D. To eliminate bias
Correct Answer: B. To summarize and organize data
Explanation:
Descriptive statistics help researchers organize, summarize, and present data in a meaningful
way through measures such as mean, median, mode, and standard deviation.
2. Which measure of central tendency is most affected by extreme scores?
A. Median
B. Mode
C. Mean
D. Range
Correct Answer: C. Mean
Explanation:
The mean includes all scores in its calculation, making it sensitive to unusually high or low
values known as outliers.
3. A researcher reports the middle score in a distribution. Which measure is being used?
A. Mean
B. Median
C. Mode
D. Variance
Correct Answer: B. Median
Explanation:
,The median represents the midpoint of an ordered dataset where half the scores fall above
and half below.
4. Which statistical measure indicates the most frequently occurring score?
A. Mean
B. Median
C. Standard deviation
D. Mode
Correct Answer: D. Mode
Explanation:
The mode identifies the value or score that appears most often in a dataset.
5. What does a large standard deviation indicate?
A. Scores are closely clustered around the mean
B. Scores are widely spread out
C. There are no outliers
D. The distribution is normal
Correct Answer: B. Scores are widely spread out
Explanation:
A large standard deviation reflects greater variability among scores, meaning data points are
spread farther from the mean.
6. Which type of variable is measured in categories without numerical meaning?
A. Interval
B. Ratio
C. Nominal
D. Continuous
Correct Answer: C. Nominal
Explanation:
Nominal variables classify data into categories such as gender or eye color without
numerical ranking or order.
7. In a positively skewed distribution, the tail extends toward:
, A. Lower scores
B. Higher scores
C. The center
D. Both directions equally
Correct Answer: B. Higher scores
Explanation:
A positive skew has a long tail stretching toward higher numerical values due to extreme
high scores.
8. Which level of measurement includes a true zero point?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
Correct Answer: D. Ratio
Explanation:
Ratio scales contain equal intervals and a meaningful zero, allowing statements like “twice as
much.”
9. What is the range in statistics?
A. Average score
B. Difference between highest and lowest scores
C. Most frequent score
D. Square root of variance
Correct Answer: B. Difference between highest and lowest scores
Explanation:
Range is a simple measure of variability calculated by subtracting the smallest value from
the largest.
10. A bell-shaped curve represents which distribution?
A. Bimodal distribution
B. Positively skewed distribution
