What is commodity : Two axiomatic answers

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CAHIER 03-2001

WHAT IS A COMMODITY? TWO AXIOMATIC ANSWERS

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CAHIER 03-2001

WHAT IS A COMMODITY? TWO AXIOMATIC ANSWERS

Yves SPRUMONT1

1

Centre de recherche et développement en économique (C.R.D.E.) and Département de sciences économiques, Université de Montréal

February 2001

_______________

The author is grateful to S. Barberà, W. Bossert, N. Meddahi, E. Renault, and O. Sprumont for stimulating conversations. He thanks the Social Sciences and Humanities Research Council of Canada for support.

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RÉSUMÉ

Nous examinons sous quelles conditions des préférences à propos d'ensembles d'options de consommation peuvent se réduire à des préférences à propos de paniers de "biens". Nous distinguons les paniers ordinaux, dont les composantes sont définies à une transformation croissante près, des paniers cardinaux, définis à une transformation linéaire positive près.

Mots clés : bien, préférence, mesure ordinale, mesure cardinale

ABSTRACT

We identify conditions under which preferences over sets of consumption opportunities can be reduced to preferences over bundles of "commodities". We distinguish ordinal bundles, whose coordinates are defined up to monotone transformations, from cardinal bundles, whose coordinates are defined up to positive linear transformations only.

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