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41.
This article analyses the effects of action aimed at narrowing the gap between South Africa's ‘two agricultures’, specifically the effects of the Farmer Support Programme (FSP) on structural aspects of maize production under different marketing policies. This is done by assembling a sectoral linear programming model of the South African summer-rainfall grain-producing area. The emphasis is on the inclusion of supply, demand and production risk. Results show that the effects of a successful FSP on specific interest groups, e.g. consumers of a specific product, or producers in a specific region, depend on the marketing policy followed, as well as on the effectiveness of the FSP. The analysis accentuates the interrelationships in South African crop production and illustrates how past policies ignored regional comparative advantages, distorted regional development and affected social welfare.  相似文献   
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Trade negotiations between Canada and the United States are to begin in the near future. For there to be an ongoing free movement of commodities the question of nontariff barriers must be addressed in the negotiations. Livestock commodities are particularly prone to nontariff barriers due to the public health aspects of domestic regulations and the perishability of the products. Potential nontariff barriers in livestock and meat products are identified and the problems of normal negotiation procedures outlined. A proposal for an arbitration mechanism for the settlement of disputes is developed. It's essential elements are pre-approval of changes to regulations, extremely short arbitration periods and decentralized adjudication.
Les négociations de commerce entre le Canada et les États-Unis commenceront bientôt. Pour avoir un mouvement continuel des denrées, la question des barrières nontarifaires doit être adressée dans les négotiations. Les denrées bestiaux sont particulièrement portées aux barrières nontarifaires à cause des aspects de la santé publique dans les régulations domestiques et la nature périssable des produits. On identifie les barrières nontarifaires potentielles en des produits bestiaux et de viande. On indique aussi les problèmes avec les processus de négotiation normale. Une proposition pour un mécanisme d'arbitrage pour la résolution des disputes est developpée. Les elements essentiels de cette proposition sont l'approbation en avance des changements aux régulations, les périodes d'arbitration très courtes et les prononcements de jugements décentralisés.  相似文献   
44.
The influence of lagged adjustment and consumer spending on retail labour productivity is investigated. Both influences result in a procyclical productivity pattern.  相似文献   
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Forecast improvement is often approached by attempting to find the “best” model for a given situation. Less attention has been paid to the possibility of examining past prediction errors for patterns that may suggest forecast adjustments for the future. This empirical study involves one firm’s management judgment forecasts for product sales and the attempts made to improve their accuracy by removing certain types of bias. In three of the five series examined, error reduction averaging close to thirty percent occurs as a result of the adjustment procedure. The other two series proved to be relatively free from bias and were therefore not in need of the correction method described.  相似文献   
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The paper asks the question – as time series analysis moves from consideration of conditional mean values and variances to unconditional distributions, do some of the familiar concepts devised for the first two moments continue to be helpful in the more general area? Most seem to generalize fairly easy, such as the concepts of breaks, seasonality, trends and regime switching. Forecasting is more difficult, as forecasts become distributions, as do forecast errors. Persistence can be defined and also common factors by using the idea of a copula. Aggregation is more difficult but causality and controllability can be defined. The study of the time series of quantiles becomes more relevant.  相似文献   
49.
Two of the main forces driving European emigration in the late nineteenth century were real wage gaps between sending and receiving regions and demographic booms in the low‐wage sending regions. Our new estimates of net migration for the countries of sub‐Saharan Africa show that exactly the same forces driving African across‐border migration are at work today. The results suggest that rapid growth in the cohort of potential young emigrants, population pressure on the resource base, and slow economic growth are likely to intensify the pressure for migration out of Africa and into high‐wage OECD countries over the next two decades.  相似文献   
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