Abstract
In this paper we say that a preference (i.e. irreflexive) relationP isregular (or aweak order) if both it and its non-comparability relation are transitive; we also say that a preference relationP * is aconvex extension of another preference relationP ifP⊆P * holds andP * is regular and convex-valued. We prove that a convex extension ofP exists if and only if every non-empty and finite set of alternativesA is not included in the convex hull of ∪ x∈A P(x).
Riassunto
In questo lavoro diciamo che una relazione di preferenza (ossia irriflessiva)P èregolare (o unordinamento debole) se tanto essa quanto la sua relazione di non paragonabilità sono transitive; diciamo anche che una relazione di preferenzaP * costituisce un'estensione convessa di un'altra relazione di preferenzaP se vale l'inclusioneP⊆P * eP * è regolare ed a valori convessi. Provereino che un'estensione convessa dellaP esiste se e solo se ogni insieme non vuoto e finito di alternativeA non è incluso nell'involucro convesso dell'insieme ∪ x∈A P(x).
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References
Bridges D. S., Metha G. B.,Representations of Preference Orderings, Springer, Berlin, 1995.
Fishburn P. C.,Utility Theory for Decision Making, John Wiley, New York, 1970.
Gay A.,Complete vs. Incomplete Preferences and Economic Behaviour, Italian Economic Papers, 1, 1992, 123–188.
Kelley J. L.,General Topology, Van Nostrand, Princeton, 1995.
Levin V. L.,Some Applications of Set-valued Mappings in Mathematical Economics, Journal of Mathematical Economics, 20, 1991, 69–87.
Mas-Colell A.,An Equilibrium Existence Theorem without Complete or Transitive Preferences, Journal of Mathematical Economics, 1, 1974, 237–246.
Peleg B., “Utility Functions for Partially Ordered Topological Spaces. Econometrica, 38, 1970, 93–96.
Richter M. K.,Revealed Preference Theory, Econometrica, 34, 1966, 635–645.
Sondermann D.,Utility Representations for Partial Orders, Journal of Economic Theory, 23, 1980, 183–188.
Szpilrajn E.,Sur l'extension de l'ordre particl, Fundamenta Mathematicae, 16, 1930, 386–389.
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Scapparone, P. Existence of a convex extension of a preference relation. Decisions Econ Finan 22, 5–11 (1999). https://doi.org/10.1007/BF02912347
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DOI: https://doi.org/10.1007/BF02912347