When would you report the median instead of the mean? Give a business example.

What the interviewer wants to hear

• Median is robust to outliers and skew
• Mean is pulled by extreme values
• Examples: income, order value, delivery time, house prices
• Report both or percentiles when distribution matters

Model answer

I use the median when the data is skewed or has outliers, because the mean gets pulled toward extreme values. For example, delivery time for a food app: most orders arrive in 30 minutes, but a few take two hours because of rain or a lost rider. The mean might say 38 minutes, which does not describe a typical order, while the median of 30 minutes does. Income, house prices and order values are similar. That said, the mean is still important when totals matter, like average revenue per user for forecasting total revenue, since total equals mean times count. Often the best answer is to show the distribution with percentiles, such as the median and the 90th percentile, because the long tail is where customer pain often hides.

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