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Statistics vocabulary · Descriptive Statistics

Quartile

Meaning in statistics, with examples

/ˈkwɔːrtaɪl/nounCommon term

In statistics, quartile means: One of the three values that divide ordered data into four equal parts: the first quartile (Q1), the median (Q2) and the third quartile (Q3).

In Turkish: çeyrek, çeyreklik, kartil

How it is used

Used to describe skewed data and to draw box plots. 'Lower quartile' and 'upper quartile' are common alternatives for Q1 and Q3. In everyday reports, 'quartile' can also mean one of the four groups: 'students in the bottom quartile'.

Example sentences

  1. The first quartile of monthly rent was 9,500 lira and the third quartile 16,000 lira.

  2. Schools in the lowest income quartile received extra funding.

Common collocations

  • first quartile
  • upper quartile
  • bottom quartile
  • lower quartile
  • percentileA value below which a given percentage of the observations fall; for example, 90% of the data lie below the 90th percentile.
  • medianThe middle value when the data are put in order from smallest to largest; with an even number of values, it is the mean of the two middle ones.
  • interquartile rangeThe distance between the first and third quartiles (Q3 − Q1), showing how spread out the middle 50% of the data is.
  • box plotA chart that shows the median, the quartiles and the spread of the data as a box with lines (whiskers) extending from it, with outliers marked as separate points.

More terms: Descriptive Statistics

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