Quartile: Difference between revisions
From Glossary of Meteorology
imported>Perlwikibot (Created page with " {{TermHeader}} {{TermSearch}} <div class="termentry"> <div class="term"> == quartile == </div> <div class="definition"><div class="short_definition">One of a set of nu...") |
imported>Perlwikibot No edit summary |
||
| Line 9: | Line 9: | ||
</div> | </div> | ||
<div class="definition"><div class="short_definition">One of a set of numbers (a [[quantile]]) on the [[random-variable]] axis that divides a [[probability distribution]] into four equal areas.</div><br/> <div class="paragraph">The three quartile points that lie between the extremes of the distribution are designated as ''Q''<sub>1</sub>, ''Q''<sub>2</sub>, ''Q''<sub>3</sub> and are defined in terms of the [[distribution function]] ''F''(''x'') as follows: <div class="display-formula"><blockquote>[[File:ams2001glos-Qe2.gif|link=|center|ams2001glos-Qe2]]</blockquote></div> Thus, ''Q''<sub>2</sub> coincides with the [[median]]. In empirical [[relative frequency]] tables, the quartiles are estimated by [[interpolation]]. The [[interquartile range]] 2''Q'' is the distance from ''Q''<sub>1</sub> to ''Q''<sub>3</sub>; half of this distance ''Q'' is called the [[semi-interquartile range]] (or quartile deviation) and is sometimes used as a crude measure of [[variability]] or [[spread]].</div><br/> </div> | <div class="definition"><div class="short_definition">One of a set of numbers (a [[quantile]]) on the [[random variable|random-variable]] axis that divides a [[probability distribution|probability distribution]] into four equal areas.</div><br/> <div class="paragraph">The three quartile points that lie between the extremes of the distribution are designated as ''Q''<sub>1</sub>, ''Q''<sub>2</sub>, ''Q''<sub>3</sub> and are defined in terms of the [[distribution function]] ''F''(''x'') as follows: <div class="display-formula"><blockquote>[[File:ams2001glos-Qe2.gif|link=|center|ams2001glos-Qe2]]</blockquote></div> Thus, ''Q''<sub>2</sub> coincides with the [[median]]. In empirical [[relative frequency]] tables, the quartiles are estimated by [[interpolation]]. The [[interquartile range]] 2''Q'' is the distance from ''Q''<sub>1</sub> to ''Q''<sub>3</sub>; half of this distance ''Q'' is called the [[semi-interquartile range]] (or quartile deviation) and is sometimes used as a crude measure of [[variability]] or [[spread]].</div><br/> </div> | ||
</div> | </div> | ||
Latest revision as of 16:41, 25 April 2012
quartile
One of a set of numbers (a quantile) on the random-variable axis that divides a probability distribution into four equal areas.
The three quartile points that lie between the extremes of the distribution are designated as Q1, Q2, Q3 and are defined in terms of the distribution function F(x) as follows: Thus, Q2 coincides with the median. In empirical relative frequency tables, the quartiles are estimated by interpolation. The interquartile range 2Q is the distance from Q1 to Q3; half of this distance Q is called the semi-interquartile range (or quartile deviation) and is sometimes used as a crude measure of variability or spread.
