<?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>1405-3195</journal-id>
<journal-title><![CDATA[Agrociencia]]></journal-title>
<abbrev-journal-title><![CDATA[Agrociencia]]></abbrev-journal-title>
<issn>1405-3195</issn>
<publisher>
<publisher-name><![CDATA[Colegio de Postgraduados]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1405-31952007000300307</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Estimación mediana-insesgada de la persistencia de perturbaciones en los precios de seis bienes primarios]]></article-title>
<article-title xml:lang="en"><![CDATA[Median-unbiased estimation of persistence of shocks to price series of six commodities]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Fernández-Cadena]]></surname>
<given-names><![CDATA[M. Andrés]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Escuela Superior Politécnica del Litoral  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Ecuador</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>05</month>
<year>2007</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>05</month>
<year>2007</year>
</pub-date>
<volume>41</volume>
<numero>3</numero>
<fpage>307</fpage>
<lpage>315</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1405-31952007000300307&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1405-31952007000300307&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1405-31952007000300307&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Este artículo examina la persistencia de las perturbaciones en los precios internacionales de seis bienes primarios que componen cerca del 70% de la canasta exportadora ecuatoriana. Utilizando el estimador mediano insesgado en series mensuales entre 1970 y el 2005, se encuentra que las perturbaciones a los precios tienen larga duración y la variabilidad de su persistencia es amplia. Las series temporales del café, cacao y camarón exhiben persistencia infinita a las perturbaciones, mientras que en el petróleo, banano y derivados del pescado, estas persistencias, aunque finitas, tienen duración variable. Se discuten las implicaciones en política de la duración típica de las perturbaciones, ya que éstas indican vías hacia el entendimiento del comportamiento de los precios y de sus tendencias, siendo insumos en el diseño de esquemas de estabilización.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract This paper examines the persistence of shocks to international prices of six basic commodities, comprising nearly 70% of Ecuadorian exports. Using the median unbiased estimator in monthly series from 1979 to 2005, it was found that the shocks to prices are of long duration and the variability of their persistence is broad. The times series of coffee, cacao, and shrimp exhibit infinite persistence to shocks, while those of crude oil, bananas and fish derivatives, although they are finite, are of variable duration. Implications of typical duration of shocks for policies are discussed since these indicate ways by which understanding of price behavior and trends can be reached, and these are inputs for designing stabilization schemes.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Estabilización]]></kwd>
<kwd lng="es"><![CDATA[impulso-respuesta]]></kwd>
<kwd lng="es"><![CDATA[vida media]]></kwd>
<kwd lng="es"><![CDATA[volatilidad]]></kwd>
<kwd lng="en"><![CDATA[Stabilization]]></kwd>
<kwd lng="en"><![CDATA[impulse-response]]></kwd>
<kwd lng="en"><![CDATA[half-life]]></kwd>
<kwd lng="en"><![CDATA[volatility]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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</article>
