This paper examines the relationship between the price for Canadian wheat and the price for U.S. wheat. While a great deal of the variation in the Canadian series can be attributed to oscillations in either the exchange rate or the U.S. price of wheat, changing technologies, shifting market power, the marketing strategies of major market participants, and domestic market conditions are also seen to play a role in the price determination process and should be considered when making longer‐term forecasts. The fact that the most encompassing price linkage specifications identified in this study differ significanty from the specification in a number of forecasting models in use today should be a point of particular concern. Since many of the decision equations (area seeded, inputs purchased, etc.) in place in these models essentially are driven off the Canada U.S. price linkage equation, the observed misspecification may have a detrimental impact on all forecasted series. Les auteurs examinent les rapports existants entre les prix canadiens et les prix américains du blé. Si une grande portion de la variabilité observée dans la série de donnée canadienne peut s'expliquer par les taux de change ou par le prix américain du blé, l'évolution des techniques, les déplacements des marchés, les stratégies de commercialisation des grands intervenants commerciaux et les conditions du marché intérieur jouent apparemment aussi un rôle dans la formation des prix. Ces facteurs devraient done être pris en compte dans les prévisions à long terme. Le fait que les spécifications de liaisons de prix les plus complètes dégagées dans cette étude s'técartent significativement de celles en usage dans plusieurs modèles de prévision mérite qu'on s'y arrête. Comme un bon nombre d'équations de décision (superficies emblavées, agrofournitures, etc.) utilisées dans ces modèles s'éloignent de l'équation de liaison de prix canado‐américaine, cet écart pourrait avoir un impact défavorable sur toutes les séries de prévisions.

This paper explores how health aspects connected with the planning of urban green space are currently supported through two types of impact assessments: health impact assessment (HIA) and environmental assessment, including strategic environmental assessment (SEA) of policies, plans and programmes and environmental impact assessment (EIA) of projects. Seven HIAs and five EIAs/SEAs from the UK, the US, the Netherlands, Austria and Germany are reviewed, using an analytical framework designed on the basis of a literature review. An important finding is that whilst all HIAs follow a problem-/objectives-driven approach, designing guidelines for potential future projects, all EIAs/SEAs use an impact-driven approach, focusing on the impacts of planned and concrete action. HIAs therefore approach policy, plan, programme and project-making exercises from the outside, making suggestions to those working on them to consider certain aspects in the future, rather than working with them on improving things within a decisionmaking process, as is usually is usually the case with EIAs/SEAs.

No abstract

No abstract

No abstract