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This paper focuses on the construction of forecasts over long horizons where a typical long-horizon forecast might span four years using 20 to 40 years’ data. It is argued that the presence of persistence in the form of unit or near-unit autoregressive roots poses substantial difficulties for long-horizon interval and point forecasting. These difficulties may not be overcome even by efficient pre-testing or model-selection procedures and might, in general, lead to point forecasts with large asymptotic root mean squared errors and undesirably wide prediction intervals.  相似文献   
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Whilst the local multiplier impacts of the annual operation of universities has been the subject of intensive research, the economic impacts of capital construction projects have been almost completely ignored. This paper presents the results of detailed analysis of capital projects at Lancaster University in 1993-The reasons for the radically different annual operation and construction multipliers estimated in the Lancaster study are examined. Despite the smaller size of construction multipliers it is argued that it is a serious mistake to estimate local construction multipliers by making simplifying assumptions on the size of the key parameters in the multiplier equations.  相似文献   
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In this paper we consider the potential gain of a government pursuing a two-part trade policy: an import license for entry, along with a per-unit tariff on imports. The model is a two-stage game of complete but imperfect information. In the first stage, the domestic government sets trade policy, while in the second stage the home and foreign producers behave as Cournot competitors. The paper demonstrates that the optimal trade policy depends upon the number of firms, the degree of heterogeneity in cost functions, and the degree of convexity in cost functions.  相似文献   
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Ohne Zusammenfassung  相似文献   
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The purpose of this study was to assess the basis behavior of the Live Cattle Futures contract at the Chicago Mercantile Exchange (CME) before and after the 1995 contract changes. Additionally, an alternative method of basis calculation utilizing weighted mean futures prices versus settlement futures prices was compared to determine which method provides a better representation of the basis level. Within a regression model with heteroskedascity error framework, we found that the level of nearby basis in the period after June 1995 has shifted lower and the average monthly open interest of net commercial long positions has substantially increased after the contract modifications. These empirical results are consistent with the notion that more long activity entered the market in response to the contract modifications. Additionally, an alternative (new) measure of basis calculation (cash price minus weighted mean futures price) produced similar results to two other commonly used measures. In conclusion, the 1995 contract changes have neither increased nor decreased the volatility of live cattle basis. © 2004 Wiley Periodicals, Inc. Jrl Fut Mark 24:557–590, 2004  相似文献   
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Cross‐docking replaces traditional warehousing, enabling continuous flow of items without storage. Here we model location‐distribution networks, that include cross‐docking facilities, to obtain the latter's impact on the supply chain. We formulate optimization models to minimize total cost in three multi‐echelon networks, each model generalizing the preceding one. The first includes a single manufacturer, one product type, and multiple customers. Cross‐docks are to be located between origin and destinations. Besides solving optimally, a tool for quantitative analysis of direct‐shipment decisions is developed. The second model considers more than one product: We determine a cost‐effective sequence of items for indirect shipment (via cross‐docks). Finally, in a network with multiple origins, optimal solutions are obtained for 40 medium‐sized and larger examples.  相似文献   
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