The interquartile range or IQR is the range of the middle half of a set of data. It is the difference between the upper quartile and the lower quartile.
The lower quartile is the value of the middle of the first set, where 25% of the values are smaller than Q1 and 75% are larger. ... This first quartile takes the notation Q1. The upper quartile is the value of the middle of the second set, where 75% of the values are smaller than Q3 and 25% are larger.
The lower quartile is the value of the middle of the first set, where 25% of the values are smaller than Q1 and 75% are larger. ... This first quartile takes the notation Q1. The upper quartile is the value of the middle of the second set, where 75% of the values are smaller than Q3 and 25% are larger.It is also called the 75th percentile. The interquartile range (IQR) is the difference between the upper (Q3) and lower (Q1) quartiles, and describes the middle 50% of values when ordered from lowest to highest.
