# How does the interquartile range relate to percentiles?

Feb 24, 2015

It's the range between the $25 t h$ and $75 t h$ percentile.

Working with quartiles means you order your cases by value and then divide into four equal groups.

The interquartile range (abbreviated as $Q 3 - Q 1$) is the difference between the first quartile and the third, these being the 'border' values between the first quarter and the second, and between the third and fourth.
In this range you'll find 50% of your values (the second and third quarter of your data).