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51.
A variety of methods and ideas have been tried for electricity price forecasting (EPF) over the last 15 years, with varying degrees of success. This review article aims to explain the complexity of available solutions, their strengths and weaknesses, and the opportunities and threats that the forecasting tools offer or that may be encountered. The paper also looks ahead and speculates on the directions EPF will or should take in the next decade or so. In particular, it postulates the need for objective comparative EPF studies involving (i) the same datasets, (ii) the same robust error evaluation procedures, and (iii) statistical testing of the significance of one model’s outperformance of another.  相似文献   
52.
Tourism demand exhibits growth cycles, and it is important to forecast turning points in these growth cycles to minimise risks to destination management. This study estimates logistic models of Hong Kong tourism demand, which are then used to generate both short- and long-term forecasts of tourism growth. The performance of the models is evaluated using the quadratic probability score and hit rates. The results show that the ways in which this information is used are crucial to the models’ predictive power. Further, we investigate whether combining probability forecasts can improve predictive accuracy, and find that combination approaches, especially nonlinear combination approaches, are sensitive to the quality of forecasts in the pool. In addition, model screening can improve forecasting performance.  相似文献   
53.
The efficient flow of goods and services involves addressing multilevel forecast questions, and careful consideration when aggregating or disaggregating hierarchical estimates. Assessing all possible aggregation alternatives helps to determine the statistically most accurate way of consolidating multilevel forecasts. However, doing so in a multilevel and multiproduct supply chain may prove to be a very computationally intensive and time-consuming task. In this paper, we present a new, two-level oblique linear discriminant tree model, which identifies the optimal hierarchical forecast technique for a given hierarchical database in a very time-efficient manner. We induced our model from a real-world dataset, and it separates all historical time series into the four aggregation mechanisms considered. The separation process is a function of both the positive and negative correlation groups' variances at the lowest level of the hierarchical datasets. Our primary contributions are: (1) establishing a clear-cut relationship between the correlation metrics at the lowest level of the hierarchy and the optimal aggregation mechanism for a product/service hierarchy, and (2) developing an analytical model for personalized forecast aggregation decisions, based on characteristics of a hierarchical dataset.  相似文献   
54.
Keynes (1930) and Samuelson (1965) proposals open the possibility of matching predictability and efficiency, as evidenced by the seminal study by Fisher (1930). Recent findings suggest that the foreign exchange market gradually incorporates relevant information allowing the formation of prices in a rational manner but not randomly. Models of exchange rate by term based on asset valuation suggest that the inclusion of risk in the spot rate increases the degree of predictability. The results show that after incorporating an accurate measure of risk, predictability of medium term foreign exchange rate increases.  相似文献   
55.
吕岩 《价值工程》2011,30(14):196-197
从DSS应用现状出发,介绍了马尔柯夫分析的定义和数学原理,阐述了马尔柯夫分析的过程和预测的基本步骤,利用Excel设计了进行市场占有率预测的应用模型,并进行了仿真预测和决策分析。测试表明,应用模型简便通用,操作方便,提高了预测的计算精度和效率。  相似文献   
56.
以哈尔滨市2000—2015年的城市人均住房使用面积和总人口数为基础,分别对总人口数建立三次指数平滑法模型,对人均住房使用面积建立二次指数平滑法模型,预测出哈尔滨市未来五年总人口数和人均住房使用面积,将总人口数和人均住房使用面积的预测结果代入M-W优化后的预测模型,更加精准的预测出了哈尔滨市未来五年的住房需求量,并对此提出对策和建议。  相似文献   
57.
但亚松 《物流科技》2010,33(6):11-13
研究同一产品在不同生命周期对配件的库存预测方法,生命周期包括新产品,成熟产品,产品生命后周期。其中对成熟产品,产品生命后周期的配件预测给出了预测公式。  相似文献   
58.
随着世界金融危机的出现,航空公司的运营效益受到了很大的影响,如何提高航空公司的经济效益是当今民航界的又一主题。文章对提高我国航空公司运行效率有一定的理论指导意义。  相似文献   
59.
文章从国内外帘子布行业的现状及其格局的重新调整,汽车、公路运输业、轮胎相关行业的现状及发展前景,加入WTO和国家宏观政策变化对帘子布行业的影响等方面进行全面、深层次的分析,应用两种数学公式模型对未来15年的国内帘子布市场需求量的上下限进行预测,并提出应对措施。  相似文献   
60.
This paper examines whether the use of non-financial information by sell-side financial analysts influences the accuracy of analysts’ forecasts. The research findings, based on a survey of Belgian financial analysts, suggest that financial analysts who use more forward-looking information and more internal-structure information offer more accurate forecasts. Furthermore, the listed Belgian firms examined in this study have improved their non-financial information reporting over time. However, neither the frequency nor the quantity of non-financial information mentioned by financial analysts in their reports appears to have increased over time.  相似文献   
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