<?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>2528-7907</journal-id>
<journal-title><![CDATA[Revista San Gregorio]]></journal-title>
<abbrev-journal-title><![CDATA[Revista San Gregorio]]></abbrev-journal-title>
<issn>2528-7907</issn>
<publisher>
<publisher-name><![CDATA[Universidad San Gregorio de Portoviejo ]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2528-79072020000400001</article-id>
<article-id pub-id-type="doi">10.36097/rsan.v1i43.1445</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Diferencias entre presupuestos referenciales y ejecutados en licitación de obra]]></article-title>
<article-title xml:lang="en"><![CDATA[Differences between reference and executed budget in public bidding processes]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ponce Zambrano]]></surname>
<given-names><![CDATA[José Miguel]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Loor Colamarco]]></surname>
<given-names><![CDATA[Ignacio Wilhem]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Pontificia Universidad Católica del Ecuador sede Manabí  ]]></institution>
<addr-line><![CDATA[Portoviejo Manabí]]></addr-line>
<country>Ecuador</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Universidad San Gregorio de Portoviejo  ]]></institution>
<addr-line><![CDATA[ Manabí]]></addr-line>
<country>Ecuador</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2020</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2020</year>
</pub-date>
<numero>43</numero>
<fpage>1</fpage>
<lpage>20</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://scielo.senescyt.gob.ec/scielo.php?script=sci_arttext&amp;pid=S2528-79072020000400001&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.senescyt.gob.ec/scielo.php?script=sci_abstract&amp;pid=S2528-79072020000400001&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://scielo.senescyt.gob.ec/scielo.php?script=sci_pdf&amp;pid=S2528-79072020000400001&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen La diferencia entre los presupuestos de contrato y ejecución en licitación de obra pública es un problema global. La literatura sugiere como causas prevalentes a la subestimación de precios referenciales de las entidades contratantes, la presentación de ofertas desequilibradas de las empresas contratistas, y la gestión de fiscalización y administración de contratos. Sin embargo, la mayoría de los estudios que abordan este problema se enfocan en la presentación de ofertas desequilibradas. El objetivo de esta investigación es identificar las obras de licitación con mayor probabilidad de que su precio ejecutado aumente en 15% o más respecto del monto contratado. Se analiza una muestra de contratos de licitación de obra publicados en el portal de compras públicas del Ecuador en el período 2008-2019. Utilizando el lenguaje de programación R, se desarrolló un modelo predictivo basado en Naïve Bayes para identificar combinaciones de parámetros de las variables región, sector, monto, plazo y entidad contratante, con probabilidad de 70% o más de que el precio ejecutado supere al contratado en 15%. El estudio identificó 15 combinaciones posibles que se circunscriben en este criterio. Este estudio puede ayudar a contratistas y a entidades contratantes para anticipar conflictos inherentes a la contratación pública.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract Differences between the estimated and final prices of government bidding processes is a global phenomenon. The literature suggests as prevalent causes the project costs underestimation by contracting entities, unbalanced offers by contractors, and the process of inspection and contract management. However, studies addressing this issue have focused primarily on the identification of unbalanced offers. This study uses a well-established machine learning approach to predict whether the reference budget of a government project will differ from the final project cost in 15% or more. A sample of contracts available on the public procurement portal of the Ecuadorian government in the period 2008-2019 is analyzed. With the help of R Core Team, the study uses Naïve Bayes predictive modeling to identify combinations of parameters for the variables region, sector, amount, term and contracting entity, with 70% or more probability that the final cost exceeds the contracted one by 15 % or more. The study identifies 15 possible combinations that can fall within this criterion. This study can help contractors identify risks that are typical of public procurement, and controlling entities to support the ability of government organizations to achieve the objectives set out in their operational and investment plans.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Contratación pública]]></kwd>
<kwd lng="es"><![CDATA[licitación de obra]]></kwd>
<kwd lng="es"><![CDATA[ofertas desequilibradas]]></kwd>
<kwd lng="es"><![CDATA[presupuesto ejecutado]]></kwd>
<kwd lng="es"><![CDATA[presupuesto referencial]]></kwd>
<kwd lng="es"><![CDATA[subestimación de precios.]]></kwd>
<kwd lng="en"><![CDATA[Cost underestimation]]></kwd>
<kwd lng="en"><![CDATA[government procurement]]></kwd>
<kwd lng="en"><![CDATA[public bidding]]></kwd>
<kwd lng="en"><![CDATA[price increase]]></kwd>
<kwd lng="en"><![CDATA[reference budget]]></kwd>
<kwd lng="en"><![CDATA[unbalanced offers]]></kwd>
</kwd-group>
</article-meta>
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