<?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>2448-718X</journal-id>
<journal-title><![CDATA[El trimestre económico]]></journal-title>
<abbrev-journal-title><![CDATA[El trimestre econ]]></abbrev-journal-title>
<issn>2448-718X</issn>
<publisher>
<publisher-name><![CDATA[Fondo de Cultura Económica]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S2448-718X2006000100005</article-id>
<article-id pub-id-type="doi">10.20430/ete.v73i289.551</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Las privatizaciones y la eficiencia a largo plazo]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Balasko]]></surname>
<given-names><![CDATA[Yves]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Paris-Jourdan Sciences Économiques  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>France</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>03</month>
<year>2006</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>03</month>
<year>2006</year>
</pub-date>
<volume>73</volume>
<numero>289</numero>
<fpage>5</fpage>
<lpage>21</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S2448-718X2006000100005&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S2448-718X2006000100005&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S2448-718X2006000100005&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen: El teorema de la envolvente de Viner-Wong afirma que los costos marginales son iguales, a largo y corto plazos, a la capacidad óptima. Este teorema implica que la combinación de la capacidad óptima a largo plazo con el comportamiento competitivo a corto plazo genera eficiencia a largo plazo. Esta propiedad se encuentra detrás de muchos proyectos de privatización de los pasados dos decenios. Exploramos aquí la solidez de esta propiedad de eficiencia a largo plazo extendiendo el contexto de equilibrio parcial de Viner-Wong a un contexto de equilibrio general simple. Demostramos entonces que la eficiencia a largo plazo no es cierta porque el modelo de corto plazo podría contener varios equilibrios de corto plazo que son ineficientes a largo plazo, excepto uno de ellos. Por tanto, es necesario complementar la capacidad óptima y el comportamiento competitivo a corto plazo por un tope para la tasa de remuneración del insumo de capital de la empresa, de modo que no exceda significativamente la remuneración de activos de riesgo comparable.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract: The Viner-Wong envelope theorem tells us that at optimum capacity, long-run and short-run marginal costs are equal. This theorem implies that the combination of long-run optimal capacity with short-run competitive behavior generates long-run efficiency. This property underlies many privatization schemes of the past two decades. We explore the robustness of this long-run efficiency property by extending the Viner-Wong partial equilibrium setup to a simple general equilibrium one. We show that long-run efficiency then fails to be true because the short-run model may feature multiple short-run equilibria that are all except one long-run inefficient. Therefore, it is necessary to supplement optimal capacity and short-run competitive behavior by a cap on the remuneration rate of the firm's capital input so that the latter does not significantly exceed the remuneration of comparably risky as sets.]]></p></abstract>
</article-meta>
</front><back>
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</article>
