Which statistic describes the percent of data below a threshold?

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

Answer: (B)

Percentiles measure where a value stands in the ordered data in terms of percentage. They tell you what percent of observations fall at or below a given threshold. For example, the 75th percentile is the value below which 75% of the data lie, so if your threshold is that value, you know what portion of data is below it. The mean is just the average value, not about cutting the data at a threshold. The range is the span from smallest to largest value, and the mode is the most frequent value. Thus, percentile is the statistic that describes the percent of data below a threshold.