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Everything about Interquartile range
Measure of statistical dispersion
In descriptive statistics, the interquartile range (IQR) is a measure of statistical dispersion, which is the spread of the data. The IQR may also be called the midspread, middle 50%, fourth spread, or H‑spread. It is defined as the difference between the 75th and 25th percentiles of the data. To calculate the IQR, the data set is divided into quartiles, or four rank-ordered even parts via linear interpolation. These quartiles are denoted by Q1, Q2, and Q3. The lower quartile corresponds with the 25th percentile and the upper quartile corresponds with the 75th percentile, so IQR = Q3 − Q1. Wikipedia →
🧭 Start here: a 6-step reading path
- Read the overview: Interquartile rangeA 5-minute orientation
- Skim a recent paper: Selecting relevant wavelength intervals for PLS calibration based on absorbance interquartile rangesInfluential work since 2022
- Pick up a classic book: Understanding Research MethodsThe most-reprinted book on the subject
- Read the landmark paper: Estimating the sample mean and standard deviation from the sample size, median, range and/or interquartile rangeCited 10,682 times
- Go sideways: QuartileA closely related topic
- Go sideways: Box plotA closely related topic
📖 Definitions
Noun The difference between the first and third quartiles; a robust measure of sample dispersion.
🗂️ The subject at a glance
🏆 Landmark papers (most cited)
Estimating the sample mean and standard deviation from the sample size, median, range and/or interquartile range
A fire risk assessment method for high-capacity battery packs using interquartile range filter
On Efficient Monitoring of Process Dispersion using Interquartile Range
General-Surrogate Adaptive Sampling Using Interquartile Range for Design Space Exploration
Feature Selection for Binary Classification Within Functional Genomics Experiments via Interquartile Range and Clustering
On Enhanced Interquartile Range Charting for Process Dispersion
On testing the equality between interquartile ranges
Q-convergence with interquartile ranges
🆕 Influential since 2022
Selecting relevant wavelength intervals for PLS calibration based on absorbance interquartile ranges
Enhancing patient rehabilitation predictions with a hybrid anomaly detection model: Density‐based clustering and interquartile range methods
Two-sided automatic censoring CFAR detector based on the interquartile range in a heterogeneous Weibull clutter
Gravity-Aided Navigation Underwater Positioning Confidence Study Based on Bayesian Estimation of the Interquartile Range Method
A study of ionospheric anomaly detection before the August 14, 2021 Mw7.2 earthquake in Haiti based on sliding interquartile range method
📚 Books worth reading
Understanding Research MethodsMildred L. Patten · 1996
Business Analytics, Global EditionEvans, James R. · 1920
Encyclopedia of Measurement and Statistics 3-Volume SetNeil J. Salkind · 2006- 📕Learning statistics with JamoviDanielle J. Navarro, David R. Foxcroft · 2025
Ranked by number of editions on Open Library, a rough measure of how lasting a book is.
🔗 Related topics
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