Statistics & Probability

Median

The middle value when the data is sorted in order. For an even count, average the two middle values.

Definition

Sort the data first. For n values: the median is at position (n + 1) ÷ 2. The median is more robust than the mean against outliers.

Example

Median of 3, 5, 7, 9, 11 is 7. Median of 3, 5, 7, 9 is (5 + 7) ÷ 2 = 6.

Used in these topics

Related terms

Mean

The arithmetic average. Sum of values divided by the number of values.

Mode

The value that appears most often. A data set can have one mode, more than one (bimodal), or no mode.

Quartile

The values that split sorted data into four equal parts. Q1 (25%), Q2 (median, 50%), Q3 (75%).

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