Confidence votes 114. Like the standard deviation, the interquartile range (IQR) is a descriptive statistic used to summarize the extent of the spread of your data. The IQR is the distance between the 1st quartile (25th percentile) and 3rd quartile (75th percentile). Q3 - Q1 = IQR. To find these numbers you must divide your data set in half, and find the median of each half and that will be your Q1 and Q3.
http://www.answers.com/Q/What_is_the_interquartile_range
To find out if there are any outliers, I first have to find the IQR. There are fifteen data points, so the median will be at position (15 + 1) ÷ 2 = 8. Then Q2 = 14.6. There are seven data points on either side of the median, so Q1 is the fourth value in the list and Q3 is the twelfth: Q1 = 14.4 and Q3 = 14.9.
http://www.purplemath.com/modules/boxwhisk3.htm
(April 2009) (Learn how and when to remove this template message) The interquartile mean (IQM) (or midmean) is a statistical measure of central tendency based on the truncated mean of the interquartile range.
https://en.wikipedia.org/wiki/Interquartile_mean
Sometimes a cut is between two numbers ... the Quartile is the average of the two numbers. The numbers are already in order. Cut the list into quarters: In this case Quartile 2 is half way between 5 and 6:
https://www.mathsisfun.com/data/quartiles.html
The IQR is the distance between the 1st quartile (25th percentile) and 3rd quartile (75th percentile). To find these numbers you must divide your data set in half, and find the median of each half and that will be your Q1 and Q3.
http://www.answers.com/Q/What_is_the_interquartile_range
In calculation of the IQM, only the data in the second and third quartiles is used (as in the interquartile range), and the lowest 25% and the highest 25% of the scores are discarded.
https://en.wikipedia.org/wiki/Interquartile_mean
From Wikipedia, the free encyclopedia. The interquartile mean (IQM) (or midmean) is a statistical measure of central tendency based on the truncated mean of the interquartile range.
https://en.wikipedia.org/wiki/Interquartile_mean
Quartiles are the values that divide a list of numbers into quarters: 1  Put the list of numbers in order. 2  Then cut the list into four equal parts.  The Quartiles are at the cuts.
https://www.mathsisfun.com/data/quartiles.html
The IQR is the length of the box in your box-and-whisker plot. An outlier is any value that lies more than one and a half times the length of the box from either end of the box. That is, if a data point is below Q1 – 1.5×IQR or above Q3 + 1.5×IQR, it is viewed as being too far from the central values to be reasonable.
http://www.purplemath.com/modules/boxwhisk3.htm
The interquartile range, abbreviated IQR, is just the width of the box in the box-and-whisker plot. That is, IQR = Q3 – Q1. The IQR can be used as a measure of how spread-out the values are. Statistics assumes that your values are clustered around some central value. The IQR tells how spread out the middle values are; it can also be used to tell when some of the other values are too far from the central value.
http://www.purplemath.com/modules/boxwhisk3.htm
what is iqr
The IQR or interquartile range is a descriptive statistic used to summarize the extent of the spread of your data. The interquartile range is a descriptive statistic used to summarize the extent of the spread of your data.