Rui Manuel de Sousa Fragoso^†

Maria Leonor da Silva Carvalho ^‡

Pedro Damião de Sousa Henriques ^‡

 ^† Universidade de Évora, Departamento de Gestão, Instituto de Ciências Agrárias Mediterrânicas (ICAM), Centro de Estudos e Formação Avançada em Gestão e Economia (CEFAGE)

rfragoso@uevora.pt

^‡ Universidade de Évora, Departamento de Economia, Instituto de Ciências Agrárias Mediterrânicas (ICAM), Centro de Estudos e Formação Avançada em Gestão e Economia (CEFAGE)

leonor@uevora.pt

pdamiao@uevora.pt

Title: Positive Mathematical Programming: an instrument for calibration and prescription of agricultural supply models.

Abstract

In this paper, calibration and prescription capacity of different types of positive mathematical programming models applied to the Alentejo agricultural sector is analysed. Model results are compared in the 2000 and 2004 agricultural price and subsidies scenarios, regarding optimal combination of activities. Results allow concluding that positive mathematical programming is an efficient instrument on calibration of agricultural supply models, as well as on prescription of their results.

Key Words: positive mathematical programming, agricultural supply, calibration, prescription.

Neste artigo avalia-se a capacidade de calibração e de prescrição de resultados de um modelo de oferta agrícola da Região Alentejo. A capacidade de calibração é analisada para o regime de preços e de ajudas agrícolas em vigor no ano 2000, comparando os resultados de diferentes formas de especificação da função dos custos variáveis totais do modelo de programação matemática positiva com os resultados do modelo tradicional de programação linear e com os dados estatísticos observados. Depois de calibrado, o modelo de programação matemática positiva é utilizado na prescrição dos resultados relativos ao cenário de preços e ajudas em vigor no ano de 2004. Conclui-se que a programação matemática positiva para além de ser um eficaz instrumento de calibração dos modelos de oferta agrícola, constitui também uma forma de prescrição de resultados futuros.

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Full text only available in PDF format.

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