偏最小二乘神经网络在建筑造价预测中的应用

偏最小二乘回归方法在提取主成分方面具有很好的解释性,而且可以避免因素之间的多重相关性,提取的成分作为输入变量再用神经网络进行预测仿真,影响因素考虑周全,不用计算工程量,计算速度快,克服了普通神经网络运算量大,样本有限情况下易出现问题的弊端。     

经济活动中关于寻租问题的博弈模型

“腐败”现象在经济活动中是经常出现的 ,一些学者也称之为“寻租” ,这种行为显然会对经济活动构成极大的危害。要想分析它必须使用博弈论的理论和方法建立起数学模型 ,对这种现象进行定量分析 ,并在完全信息和不完全信息两种情况下 ,分别给出了纳什均衡和贝叶斯纳什均衡。这样 ,才能根据模型的结论 ,采取相关的对策。     

基于投资者行为参数的股票指数广义回归神经网络预测模型

在运用神经网络模型对股票价格进行短期预测时,一般的神经网络预测模型都是以价格的时间序列滞后作为输入变量,但是由于影响价格的因素错综复杂,很多因素无法准确测量,而且市场信息的噪音太大,因此预测效果往往不太理想,于是如何选择有效的输入变量就成为一个困扰这项研究的难题。     

Trip Cultural Activities and Tourism Expenditure in Emerging Urban‐cultural Destinations

Although tourism expenditure is determined by different factors, the literature has not analysed the extent to which trip cultural activities affect tourism expenditure in the destination. The focus of this paper is a microeconomic analysis performed in 14 emerging urban‐cultural destinations in Andalusia (Spain). The results confirm that there are activities related to cultural visits, attendance at events or gastronomic activities that determine tourism expenditure. These results guide the implementation of specific actions by the policy‐makers in these destinations aimed at increasing the economic impact of tourism, based on the creation of high value‐added tourism products to overcome their mere dependence on built heritage. Copyright © 2015 John Wiley & Sons, Ltd.     

A travel demand model for Mainland Chinese tourists to Hong Kong

The purpose of the study was to determine what exogenous variables best explained the travel demand for Mainland Chinese tourists to Hong Kong. The 12 years (1984–1995) annual time series data of ‘number of Mainland Chinese tourist arrivals’, ‘China disposable income per capita’, ‘consumer price indices in Hong Kong and China’ and ‘exchange rates’ was used to develop a travel demand model. Seven exogenous variables were selected for the model through a literature review. An OLS multiple regression analysis was performed to identify the ‘best’ subset of seven exogenous variables to determine the demand model. The results showed that travel demand for Mainland Chinese tourists to Hong Kong could be explained by ‘disposable income per capita’ and ‘relaxation of visa requirements’.     

学科差异下的大学英语成绩——基于北京市七所高校本科生的分析

在对北京市海淀区七所"211工程"高校计算机及经管专业大四本科学生问卷调查的基础上,及在将新、旧四六级成绩统一转化为可比的旧四级成绩后,利用一般MLE回归模型纠正、解释了学科差异与大学英语成绩间的生态学谬误。学科差异对于个人的英语成绩并不存在直接影响。还利用国外教育界经常采用的分层线性模型重新估计了学科差异对于我国大学生英语成绩的影响。在理工科学生组中,解释变量对于因变量的影响更为强烈。     

Consumer preference among fluid milks: low‐fat vs. high‐fat milk consumption in the United States

The present study uses data from the Continuing Survey of Food Intakes by Individuals 1994–1996, 1998 in order to analyse milk consumption by type, specifically high‐fat milk vs. low‐fat milk. Whereas trend analysis displays an overall increase in low‐fat milk consumption over the last few decades in the United States, a number of individuals still consume high‐fat milk varieties, and overall dietary intakes have yet to achieve recommended levels. In light of recent research regarding fat intakes, it is important to understand what factors might cause consumers to purchase high‐fat options given the number of low‐fat options available in the market. Through the use of Logistic regression, key socio‐economic and demographic variables are analysed in order to determine their impacts on the probability of consuming low‐fat milk vs. high‐fat milk. The results indicate that a number of factors do influence probability of low‐fat milk consumption as compared with high‐fat milk consumption. Most notably, probability of low‐fat milk consumption appears to be positively related to age, education level, and income level. African Americans and other minorities had a lower probability of consuming low‐fat milk when compared with White people in the sample population. Also, those respondents designated as low income or living in the South were less likely to consume low‐fat milk.     

探究我国上市公司股利政策的实证研究——基于代理成本理论

采用多元回归的方法研究派现与上市公司三种不同代理成本之间的关系。实证发现,派现能降低股东与管理者的代理成本,正常现金股利发放只是大股东获取公共收益的一种手段,不能缓解大小股东之间的利益冲突,降低大股东的私有收益。     

THE ROLE OF THE EXCHANGE RATE IN A NEW KEYNESIAN DSGE MODEL FOR THE SOUTH AFRICAN ECONOMY

We build a small open economy New Keynesian dynamic stochastic general equilibrium model for South Africa similar to Steinbach et al. We abandon their assumption of complete risk sharing with the foreign economy, and introduce country risk shocks to allow deviations from uncovered interest rate parity. These changes allow us to include the exchange rate as an observable variable in the estimation of the model. Using forecast error variance decompositions and historical decompositions, we show that country risk shocks have sizable effects on the South African business cycle. We also explore the optimal monetary policy implications of our model within the context of Taylor rules.     

城镇医疗保险改革对预防性储蓄有挤出效应吗？

利用中国健康与营养调查（CHNS）数据和倍差法,分析1998年的城镇医疗保险改革对预防性储蓄的影响,实证发现：城镇医疗保险改革对预防性储蓄没有挤出效应;对贫困个体而言,医疗保险改革甚至使其增加了预防性储蓄。医疗支出风险并没有随着改革的推进而降低,是我国城镇医疗保险改革对储蓄没有影响的重要原因。