In a small dataset, which measure is more robust to outliers: median or mean?

In a small dataset, which measure is more robust to outliers: median or mean?

• A. Median
• B. Mean
• C. Mode
• D. Range

Answer: (A)

When summarizing data, robustness to outliers is the key idea. The median is more robust because it depends on the middle value(s) after sorting the data, not on how big or small the extreme observations are. In a small dataset, an outlier can pull the mean toward itself, dramatically changing the average, while the median stays near the center of the data. For example, with values like 1, 2, 3, 100, the mean is 26.5, but the median is 2.5. The median thus better represents the typical observation when outliers are present. The mode is about the most frequent value, not a measure of central tendency in the sense of an average, and the range describes spread, not a central value. So the median is the more robust choice.

When summarizing data, robustness to outliers is the key idea. The median is more robust because it depends on the middle value(s) after sorting the data, not on how big or small the extreme observations are. In a small dataset, an outlier can pull the mean toward itself, dramatically changing the average, while the median stays near the center of the data. For example, with values like 1, 2, 3, 100, the mean is 26.5, but the median is 2.5. The median thus better represents the typical observation when outliers are present. The mode is about the most frequent value, not a measure of central tendency in the sense of an average, and the range describes spread, not a central value. So the median is the more robust choice.