The interquartile range, or IQR, can be found after the median has been determined by dividing the data sets that are above and below the median in half, which divides the entire set into quarters, and then combining the second quarter with the third quarter.
Once you've determined your first and third quartiles, calculate the interquartile range by subtracting the value of the first quartile from the value of the third quartile. To finishing the example used over the course of this article, you would subtract 8.5 from 17 to find that the interquartile range of the data set equals 8.5.
Finding the TI 83 interquartile range involves nothing more than entering your data list and pushing a couple of buttons. Sample problem: Find the TI 83 interquartile range for the heights of the top 10 buildings in the world (as of 2009). The heights, (in feet) are: 2717, 2063, 2001, 1815, 1516, 1503, 1482, 1377, 1312, 1272.
In descriptive statistics, the interquartile range (IQR), also called the midspread or middle 50%, or technically H-spread, is a measure of statistical dispersion, being equal to the difference between 75th and 25th percentiles, or between upper and lower quartiles, IQR = Q 3 − Q 1.
How to Find the IQR. The IQR is the "interquartile range" of a data set. It is used in statistical analysis to help draw conclusions about a set of numbers. The IQR is often preferred over the range because it excludes most outliers. Read...
Once we have determined the values of the first and third quartiles, the interquartile range is very easy to calculate. All that we have to do is to subtract the first quartile from the third quartile. This explains the use of the term interquartile range for this statistic.
The interquartile range is defined as follows: Interquartile Range = Q 3-Q 1. With an Even Sample Size: For the sample (n=10) the median diastolic blood pressure is 71 (50% of the values are above 71, and 50% are below). The quartiles can be determined in the same way we determined the median, except we consider each half of the data set ...
Find IQR using interquartile range calculator which is the most important basic robust measure of scale and variability on the basis of division of data set in the quartiles. Use this online interquartile range (IQR) calculator to find the values of first quartile, third quartile, median and inter quartile range.
Interquartile Ranges & Outliers. Quartiles & Boxes 5-Number Summary IQRs & Outliers. Purplemath. The "interquartile range", abbreviated "IQR", is just the width of the box in the box-and-whisker plot. That is, IQR = Q 3 – Q 1. The IQR can be used as a measure of how spread-out the values are.
The range, inter-quartile range and standard deviation are all measures that indicate the amount of variability within a dataset. The range is the simplest measure of variability to calculate but can be misleading if the dataset contains extreme values.