AI Grounds

Open AI Grounds on a desktop

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Guided discovery

Range, Quartiles & IQR

Move one point. Watch two measures of spread.

Your dataset

Drag a dot to change its value
Values

Box plot: minimum 18, Q1 26, median 36, Q3 46, maximum 58.

IQR (interquartile range) is the box width, from Q1 to Q3. The line inside marks the median; whiskers show min and max.

Focus a dot and use arrow keys. Shift moves by 10; Home / End moves to 0 / 100.

Sorted values

Lower half

  1. 18A
  2. 24B
  3. 28C
  4. 32D

Q1 = (24 + 28) / 2 = 26

Median

  1. 36E

Median = 36

Upper half

  1. 40F
  2. 44G
  3. 48H
  4. 58I

Q3 = (44 + 48) / 2 = 46

Median-of-halves rule: exclude the fifth value, then average each half’s middle pair. Other conventions can differ.

Range

The full span.

40

58 − 18 = 40

Before 40 → now 40

IQR

The middle 50%.

20

46 − 26 = 20

Before 20 → now 20

Point I: 58. Range 40; Q1 26; median 36; Q3 46; IQR 20.