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Interquartile range Definition

The difference between the 25th percentile (first quartile) and the 75th percentile (third quartile) in an ordered array of data. This range contains the middle 50% of the data.

The interquartile range (IQR) is a statistical measure of variability that represents the range between the 25th percentile (Q1) and the 75th percentile (Q3) of a dataset. It shows the spread of the middle 50% of values.

What are the key aspects of interquartile range in marketing research?

• Calculated as Q3 minus Q1.
• Less affected by outliers than the full range.
• Highlights the central tendency and variability.
• Useful for understanding distribution in skewed data.
• Often visualized in box plots.

Why is interquartile range important in market research?

IQR helps identify the consistency or dispersion in responses, especially when analyzing satisfaction scores, pricing sensitivity or behavioral data. It provides a clearer picture of variability without being skewed by extreme values.

Who relies on interquartile range in marketing research?

• Data analysts.
• Quantitative researchers.
• Statisticians.
• Insights and analytics teams.
• CX and satisfaction measurement professionals.

How do market researchers use interquartile range?

Researchers use IQR to assess data spread, detect outliers, compare segment variability and support robust statistical reporting. It is commonly used in survey analysis, concept testing and when evaluating central trends in customer feedback.