Descriptive Statistics Online Test for Data Science (Free MCQs)

1. Which measure of central tendency is most affected by extreme values?

• (a) Mean
• (b) Median
• (c) Mode
• (d) None

2. The middle value of an ordered dataset is called:

• (a) Mean
• (b) Median
• (c) Mode
• (d) Range

3. The measure representing the most frequent value in a dataset is:

• (a) Mean
• (b) Median
• (c) Mode
• (d) Variance

4. The difference between the maximum and minimum values of a dataset is:

• (a) Mean
• (b) Range
• (c) Variance
• (d) Standard deviation

5. Variance measures:

• (a) Central tendency
• (b) Dispersion
• (c) Probability
• (d) Skewness

6. Standard deviation is the:

• (a) Square of variance
• (b) Square root of variance
• (c) Twice the variance
• (d) None

7. The interquartile range (IQR) measures:

• (a) Spread of all values
• (b) Spread of middle 50% of values
• (c) Central tendency
• (d) Skewness

8. Skewness indicates:

• (a) Mean value
• (b) Symmetry of data
• (c) Median value
• (d) Variance

9. For a perfectly symmetric dataset:

• (a) Mean = Median = Mode
• (b) Mean > Median
• (c) Median > Mode
• (d) Mean < Mode

10. Which measure is least affected by outliers?

• (a) Mean
• (b) Median
• (c) Variance
• (d) Standard deviation

11. A box plot is used to visualize:

• (a) Frequency distribution
• (b) Spread and central tendency
• (c) Probability distribution
• (d) Correlation

12. The sum of deviations of all data points from the mean is:

• (a) Positive
• (b) Negative
• (c) Zero
• (d) Depends on data

13. A dataset with a few extreme values has:

• (a) Low variance
• (b) High variance
• (c) Zero mean
• (d) Zero range

14. Which plot best visualizes the distribution of a single quantitative variable?

• (a) Pie chart
• (b) Histogram
• (c) Scatter plot
• (d) Line chart

15. The formula for population variance is:

• (a) $\frac{\sum (x_i – \bar{x})^2}{n}$
• (b) $\frac{\sum (x_i – \bar{x})^2}{n-1}$
• (c) $\sum x_i$
• (d) $\sum x_i^2$