ON THE RELATION BETWEEN USERS' BENEFITS AND THE ECONOMIC EFFECTS OF TRANSPORTATION ACTIVITIES

ABSTRACT. The addition of output variation benefits to the users' surplus generated by transportation improvements has been subject to debate, and no agreement has been reached. In this paper, the problem is restated at the level of the origins of transportation demand, which can be derived from the information provided by the economic activity. It is shown that a competitive productive environment makes the transportation consumers' surplus exactly equal to the net economic benefits provoked in the products' markets; however, when monopolistic production prevails, the users' surplus may not reflect the benefits to the economy with accuracy. Mixed conditions are also explored and the role of final products' demand elasticity is highlighted. Different styles of welfare analysis are recommended for different market conditions.     

Seasonality and seal exploitation in the southwestern Cape,South Africa

An ecological model is proposed for human responses to climatic seasonality in the later Holocene of the southwestern Cape in South Africa. This is an area where pronounced seasonality produces cyclical effects on plant, animal and human communities. The predictions of this model are that: 1. human foragers would switch from plant carbohydrates to seal fat as a winter energy source; 2. capture and butchery of seals would vary with season and seal age; 3. capture and butchery of ungulates would vary seasonally; and 4. seals would be exploited differently from ungulates throughout the year. The model is tested against faunal data from Smitswinkelbaai Cave.

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Résumé On propose un modèle écologique des réactions humaines à la saisonalité climatique pour l'Holocène récent dans le cap sud-ouest, Afrique du Sud. C'est une région où la saisonalité produit des effets cycliques sur les communautés végétale, animale et humaine. Les prédictions de ce modèle sont les suivantes: 1. les cueilleurs humains changeaient des féculents végétaux à la graisse de phoque comme source d'énergie en hiver; 2. la prise et la boucherie de phoques variaient avec les saisons et selon l'âge des phoques; 3. la prise et la boucherie des ongulés variaient de façon saisonnière; et 4. les phoques étaient exploités différemment des ongulés pendant toute l'année. On présente un essai préliminaire du modèle sur les données de la caverne Smitswinkelbaai.