<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0120-1751</journal-id>
<journal-title><![CDATA[Revista Colombiana de Estadística]]></journal-title>
<abbrev-journal-title><![CDATA[Rev.Colomb.Estad.]]></abbrev-journal-title>
<issn>0120-1751</issn>
<publisher>
<publisher-name><![CDATA[Departamento de Estadística - Universidad Nacional de Colombia.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0120-17512007000100004</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Cálculo de los estimadores de regresión cuantílica lineal por medio del método ACCPM]]></article-title>
<article-title xml:lang="en"><![CDATA[Calculus of the Estimators of Linear Quantile Regression by the Method ACCPM]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[LÓPEZ]]></surname>
<given-names><![CDATA[HÉCTOR ANDRÉS]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[MORA]]></surname>
<given-names><![CDATA[HÉCTOR MANUEL]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Universidad de la Sabana Facultad de Ingeniería Área de Matemáticas Aplicadas y Estadística]]></institution>
<addr-line><![CDATA[Chía ]]></addr-line>
<country>Colombia</country>
</aff>
<aff id="A02">
<institution><![CDATA[,Universidad Nacional de Colombia Facultad de Ciencias Departamento de Matemáticas]]></institution>
<addr-line><![CDATA[Bogotá ]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>15</day>
<month>06</month>
<year>2007</year>
</pub-date>
<pub-date pub-type="epub">
<day>15</day>
<month>06</month>
<year>2007</year>
</pub-date>
<volume>30</volume>
<numero>1</numero>
<fpage>53</fpage>
<lpage>68</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0120-17512007000100004&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0120-17512007000100004&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0120-17512007000100004&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Se muestra cómo calcular los estimadores en regresión cuantílica por medio del método de optimización no diferenciable ACCPM (Analytic Center Cutting Plane Method). El cálculo de dichos estimadores usualmente se encuentra por medio de programación lineal y sus respectivas técnicas de solución (método simplex, métodos de punto interior, etc.). La primera parte presenta las generalidades de la regresión cuantílica y su formulación como un problema de programación lineal. Además, se realiza una breve descripción del método ACCPM. Por último, se muestra la aplicación del método ACCPM para el cálculo de estimadores por cuantiles y los resultados numéricos y comparaciones del método ACCPM con el paquete estadístico R y el paquete de optimización GAMS.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[The present work shows how to calculate the estimators in quantile regression by nondifferentiable optimization method ACCPM (Analytic Center Cutting Plane Method). The calculus of the estimators is usually found by linear programming and its respective techniques of solution (Simplex method, interior point methods, etc.). The first part presents some generalities of quantile regression and its formulation as a linear programming problem. Also, a brief description of the ACCPM method is made. Finally, it is shown the application of the ACCPM method for the calculation of the estimators by quantiles and the numerical results and comparisons of the ACCPM with the statistic package R and the optimization package GAMS.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[optimización]]></kwd>
<kwd lng="es"><![CDATA[estimador de regresión]]></kwd>
<kwd lng="es"><![CDATA[programación lineal]]></kwd>
<kwd lng="es"><![CDATA[estimación cuantílica]]></kwd>
<kwd lng="en"><![CDATA[Optimization]]></kwd>
<kwd lng="en"><![CDATA[Regression estimator]]></kwd>
<kwd lng="en"><![CDATA[Linear programming]]></kwd>
<kwd lng="en"><![CDATA[Quantile estimation]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[   <font face="verdana" size="2">      <p><b><font size="4">    <center>C&aacute;lculo de los estimadores de regresi&oacute;n cuant&iacute;lica lineal por medio del m&eacute;todo ACCPM</center></font> </b></p>      <p><b><font size="3">    <center>Calculus of the Estimators of Linear Quantile Regression by the Method ACCPM</center></font> </b></p>      <p>    <center>H&Eacute;CTOR ANDR&Eacute;S L&Oacute;PEZ<sup>1</sup>, H&Eacute;CTOR MANUEL MORA<sup>2</sup></center></p>      <p> <sup>1</sup>Universidad de la Sabana, Facultad de Ingenier&iacute;a, &Aacute;rea de Matem&aacute;ticas Aplicadas y Estad&iacute;stica, Ch&iacute;a, Colombia. Profesor. E-mail: <a href="mailto:hector.lopez1@unisabana.edu.co">hector.lopez1@unisabana.edu.co</a>    <br>  <sup>2</sup>Universidad Nacional de Colombia, Facultad de Ciencias, Departamento de Matem&aacute;ticas, Bogot&aacute;. Profesor titular. E-mail: <a href="mailto:hmmorae@unal.edu.co">hmmorae@unal.edu.co</a> </p>  <hr size=1>      <p><b>    ]]></body>
<body><![CDATA[<center>Resumen</center></b></p>      <p>  Se muestra c&oacute;mo calcular los estimadores en regresi&oacute;n cuant&iacute;lica por medio del m&eacute;todo de optimizaci&oacute;n no diferenciable ACCPM (Analytic Center Cutting Plane Method). El c&aacute;lculo de dichos estimadores usualmente se encuentra por medio de programaci&oacute;n lineal y sus respectivas t&eacute;cnicas de soluci&oacute;n (m&eacute;todo simplex, m&eacute;todos de punto interior, etc.). La primera parte presenta las generalidades de la regresi&oacute;n cuant&iacute;lica y su formulaci&oacute;n como un problema de programaci&oacute;n lineal. Adem&aacute;s, se realiza una breve descripci&oacute;n del m&eacute;todo ACCPM. Por &uacute;ltimo, se muestra la aplicaci&oacute;n del m&eacute;todo ACCPM para el c&aacute;lculo de estimadores por cuantiles y los resultados num&eacute;ricos y comparaciones del m&eacute;todo ACCPM con el paquete estad&iacute;stico R y el paquete de optimizaci&oacute;n GAMS. </p>      <p>     <p><b>Palabras clave:</b> optimizaci&oacute;n, estimador de regresi&oacute;n, programaci&oacute;n lineal, estimaci&oacute;n cuant&iacute;lica.</p>  <hr size=1>      <p><b>    <center>Abstract</center></b></p>      <p> The present work shows how to calculate the estimators in quantile regression by nondifferentiable optimization method ACCPM (Analytic Center Cutting Plane Method). The calculus of the estimators is usually found by linear programming and its respective techniques of solution (Simplex method, interior point methods, etc.). The first part presents some generalities of quantile regression and its formulation as a linear programming problem. Also, a brief description of the ACCPM method is made. Finally, it is shown the application of the ACCPM method for the calculation of the estimators by quantiles and the numerical results and comparisons of the ACCPM with the statistic package R and the optimization package GAMS. </p>      <p><b>Key words:</b> Optimization, Regression estimator, Linear programming, Quantile estimation.</p>  <hr size=1>      <p>Texto completo disponible en <a href="pdf/rce/v30n1/v30n1a04.pdf">PDF</a></p>  <hr size=1>      <p><b><font size="3">Referencias</font></b></p>      ]]></body>
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