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71.
Copulas provide an attractive approach to the construction of multivariate distributions with flexible marginal distributions and different forms of dependences. Of particular importance in many areas is the possibility of forecasting the tail-dependences explicitly. Most of the available approaches are only able to estimate tail-dependences and correlations via nuisance parameters, and cannot be used for either interpretation or forecasting. We propose a general Bayesian approach for modeling and forecasting tail-dependences and correlations as explicit functions of covariates, with the aim of improving the copula forecasting performance. The proposed covariate-dependent copula model also allows for Bayesian variable selection from among the covariates of the marginal models, as well as the copula density. The copulas that we study include the Joe-Clayton copula, the Clayton copula, the Gumbel copula and the Student’s t-copula. Posterior inference is carried out using an efficient MCMC simulation method. Our approach is applied to both simulated data and the S&P 100 and S&P 600 stock indices. The forecasting performance of the proposed approach is compared with those of other modeling strategies based on log predictive scores. A value-at-risk evaluation is also performed for the model comparisons.  相似文献   
72.
The main objectives of this study are (1) to identify the factors that influence the demand for hotel rooms in Hong Kong and (2) to generate quarterly forecasts of that demand to assess the impact of the ongoing financial/economic crisis. The demand for four types of hotel room from the residents of nine major origin countries is considered, and forecasts are generated from the first quarter of 2009 to the fourth quarter of 2015. Econometric approaches are employed to calculate the demand elasticities and their corresponding confidence intervals, which are then used to generate interval demand predictions. The empirical results reveal that the most important factors in determining the demand for hotel rooms in Hong Kong are the economic conditions (measured by income level) in the origin markets, the price of the hotel rooms and the ‘word of mouth’ effect. Demand for High Tariff A and Medium Tariff hotel rooms is estimated to have experienced negative annual growth in 2009 due to the influence of the financial/economic crisis, whereas that for High Tariff B hotel rooms is thought to have grown in 2009 after having decreased in 2008. The demand for tourist guesthouse rooms is expected to be the least affected by the crisis. Overall demand is predicted to recover gradually from 2010 onwards.  相似文献   
73.
We present a simple quantile regression-based forecasting method that was applied in the probabilistic load forecasting framework of the Global Energy Forecasting Competition 2017 (GEFCom2017). The hourly load data are log transformed and split into a long-term trend component and a remainder term. The key forecasting element is the quantile regression approach for the remainder term, which takes into account both weekly and annual seasonalities, such as their interactions. Temperature information is used only for stabilizing the forecast of the long-term trend component. Information on public holidays is ignored. However, the forecasting method still placed second in the open data track and fourth in the definite data track, which is remarkable given the simplicity of the model. The method also outperforms the Vanilla benchmark consistently.  相似文献   
74.
在海南远期经济指标的预测过程中,时间跨度较大,经济社会发展的不确定因素很多,利用传统的数学模型不易把握其发展态势,难以预测。借鉴管理学上“标杆管理”的模式成功地对海南远景经济指标进行了分析预测,该思路同样适用于其他区域经济远景指标的预测。  相似文献   
75.
本文给出了E-Bayes方法,以上海证券个股五粮液52个连续交易日的收盘价格为例,建立数学模型进行分析和预测,预测结果与市场实际值相当吻合。与灰色系统理论中的GM(1,1)预测模型相比,本文提出的方法预测的精度更高,计算量小。不仅适用于经济系统的分析与预测,也适用于其它系统的分析与预测。  相似文献   
76.
The Asian financial crisis has drawn worldwide attention because of its significant economic impact on local economics, especially on the economy of a tourism‐dependent destination. Unfortunately, there have been very few articles about the relationship of the Asian financial crisis and tourism demand forecasting. This relative lack of prior studies on the Asian financial crisis and tourism demand forecasting is particularly true in the context of Hong Kong. This article reports on a study that utilized officially published data to test the accuracy of forecasts of Japanese demand for travel to Hong Kong, measured in terms of the number of Japanese tourist arrivals. Seven commonly‐used tourism forecasting techniques were used to determine the forecasting accuracy. The quality of forecasting accuracy was measured in five dimensions. Experimental results indicated mixed results in terms of forecasting accuracy. Overall, artificial neural network outperformed other techniques in three of the five dimensions.  相似文献   
77.
Abstract

Numerous outdoor recreation forecasting studies have included household characteristics as well as aspects of the recreation facilities and accessibility. Only a few studies, however, have included in the prediction equation any measure of the effects of urban milieu on behavior. Four commonly cited surrogates of urban milieu are used to cluster the cities of Illinois into three relatively homogeneous groups of environments. Regression analyses are then undertaken using individual household data, aspects of the recreation facilities patronized by the households, participation, and distance and travel time estimates. Comparisons of the regression analyses indicate that, as a concept, milieu is an important predictor of both the volume of recreation participation and salient features of recreation facilities.  相似文献   
78.
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   
79.
Economic forecasts are useful to policymakers both as aids to planning, and as baselines against which counterfactual scenarios can be compared. However, policy makers should be aware that assumptions relating to model structure can influence forecast results. We explore the sensitivity of forecasts to one aspect of model structure important in modelling developing economies: surplus agricultural labour. We outline a framework for modelling surplus agricultural labour that relies on average product remuneration. We embed this within a model of a developing economy (the Philippines) characterized by surplus agricultural labour. We compare the results of two forecasts that differ in their treatment of the agricultural labour market. In the first, the surplus labour theory is activated, establishing average product remuneration in agriculture. In the second, the surplus labour theory is not activated, creating a failure to recognize average product remuneration in agriculture. By comparing the two simulations, we show that failure to model the presence of average product remuneration, when it would be appropriate to do so, has an impact that would be material to economic planners, leading them to: under-estimate agricultural employment; over-estimate GDP growth; and, over-estimate important policy variables (like tax revenue) that are related to GDP growth.  相似文献   
80.
This article provides out-of-sample forecasts of linear and nonlinear models of US and four Census subregions’ housing prices. The forecasts include the traditional point forecasts, but also include interval and density forecasts, of the housing price distributions. The nonlinear smooth-transition autoregressive model outperforms the linear autoregressive model in point forecasts at longer horizons, but the linear autoregressive and nonlinear smooth-transition autoregressive models perform equally at short horizons. In addition, we generally do not find major differences in performance for the interval and density forecasts between the linear and nonlinear models. Finally, in a dynamic 25-step ex-ante and interval forecasting design, we, once again, do not find major differences between the linear and nonlinear models. In sum, we conclude that when forecasting regional housing prices in the United States, generally the additional costs associated with nonlinear forecasts outweigh the benefits for forecasts only a few months into the future.  相似文献   
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