我国城镇住宅产品供给结构的构建研究

在快速发展的过程中,我国房地产市场存在着住宅产品的供给结构不均衡的现象。论文分析了住宅产品供给不均衡的现象及原因,以浙江省为例,结合非均衡理论、梯度消费模型,从需求引导供给的角度,构建了合理的住宅产品的供给结构,提出了可操作的程序。     

产业集群对产业“梯度转移”理论的挑战

产业集群是我国东部沿海地区经济增长和竞争优势的主要来源 ,东部产业集群效应使东部地区强化了“后天优势” ,阻碍了东部产业向中西部的转移 ,对流行的产业“梯度转移”理论形成了重要挑战。东部地区利用西部低成本劳动力优势及高度专业化分工基础上的产业配套条件 ,使中西部地区利用产业“梯度转移”理论发展经济的难度加大了。     

贵州省近10年地闪分布特征分析

[目的]为系统分析研究贵州省地闪活动规律。[方法]利用2008—2017年ADTD闪电定位监测资料,主要采用数理统计和分析方法,结合ArcGIS插值,[结果]贵州省年平均地闪频次为44.5153万次,负地闪占总地闪的95.61%,3—10月、15h开始至次日2h闪电发生频繁,负地闪月分布呈现“双峰”特征,正地闪月分布呈现“单峰”特征,正地闪比例与总地闪频数发展趋势相反,地闪密度呈明显的西高东低区域分布;年平均雷电流强度为41.14kA,12月、10h雷电流强度最强,02h^13h的平均雷电流强度明显大于14h至次日01h;雷电流强度主要集中在10~50kA,占总地闪数的79.21%,贵阳市平均总地闪雷电流强度最大,为45.32kA,在高海拔地区正地闪的平均强度随着海拔高度上升不断增加;总地闪平均陡度为10.350kA/μs,陡度在8.2kA/μs以上的地闪频次占总地闪频次的50%。[结论]分析得出了贵州省地闪频次、雷电流幅值的时空分布、陡度分布特征,得到了雷电流幅值累积概率公式。     

我国外商投资梯度转移问题研究

改革开放以来，我国吸引的外商直接投资绝大部分分布于东部沿海地区，但近年来外商在华投资区域分布变化非常明显。通过调研，本文分析了“北上”是外商投资区域间转移的主要特征及原因，而“西进”不是目前外资进行区域间转移的主要方向，但中部地区吸引外资相对较好，并指出其原因；同时，调研中还发现，沿海地区外资向所在省较落后地区转移的现象明显。最后，本文提出进一步促进外商投资梯度转移的政策建议。     

神经网络与Logistic回归在基础研究成果综合评价中的应用比较

应用现代数理统计、系统综合评价及科学计量学方法构建对基础性研究成果的综合评价系统.在以科学计量学和数理统计方法处理综合评价指标集输入数据的基础上,通过Logistic回归和神经网络（网络类型为多层感知器,训练算法采用共轭梯度下降法）实现对基础研究成果多指标的综合评价并比较二法的评价效果.     

Housing-choice hindrances and urban spatial structure: Evidence from matched location and location-preference data in Chinese cities

In a monocentric city with a well-functioning residential market, Pareto-efficient spatial equilibrium entails the sorting of residents according to their bid–rent gradient in descending order away from city center. Violation of this sorting condition creates opportunities for Pareto-improving trading of locations and can be sustained only if the market is hindered. We propose a simple ordered-location-choice model using matched location and location-preference data of individual households to examine violations of the Pareto-efficient spatial sorting condition. In so doing we are able to identify population groups facing housing-choice hindrances. We find in a sample of Chinese cities undergoing housing market liberalization that poor marketability of the previously state-provided homes, inadequate provision of housing finance, and spatial mismatch between job-market and housing-market opportunities contribute to a Pareto-inefficient spatial structure.     

中国一级城市入境旅游流时空演变模式分析

对北京、上海和广州入境旅游流的流量、时间、流向等因子进行分析,发现流量特征具有较强的区位引导效应,时间特征具有很强的资源制约效应,流向特征具有很强的交通线路引导效应,指出城市入境旅游发展受经济、资源、区位三个主要因素共同作用.     

MODEL‐INDEPENDENT NO‐ARBITRAGE CONDITIONS ON AMERICAN PUT OPTIONS

We consider the pricing of American put options in a model‐independent setting: that is, we do not assume that asset prices behave according to a given model, but aim to draw conclusions that hold in any model. We incorporate market information by supposing that the prices of European options are known. In this setting, we are able to provide conditions on the American put prices which are necessary for the absence of arbitrage. Moreover, if we further assume that there are finitely many European and American options traded, then we are able to show that these conditions are also sufficient. To show sufficiency, we construct a model under which both American and European options are correctly priced at all strikes simultaneously. In particular, we need to carefully consider the optimal stopping strategy in the construction of our process.     

Differentiating peri-urban areas: A transdisciplinary approach towards a typology

Peri-urban areas have no clear boundaries, both in geographic and conceptual terms. This paper presents a transdisciplinary approach for the identification of typologies of peri-urban areas and applies it to the Lisbon Metropolitan Area (LMA), Portugal. It is based on the assumptions that more than one type of peri-urban region around an urban core can exist, and that a transdisciplinary approach, linking the physical, economic, social and personal aspects, is needed to capture the intrinsic variability and the complexity of the peri-urban character. The approach is based on four sequential steps: (i) identifying the important peri-urban dimensions to be considered, based on expert-knowledge and stakeholder perspectives; (ii) defining a set of indicators for each dimension; (iii) summarizing redundant information for each dimension; and (iv) applying cluster analysis to identify typologies of peri-urban. This approach was applied to the 211 parishes comprised in the LMA. Seven types of parishes were identified, of which two can be considered urban and five peri-urban, although with quite distinct features. This approach has the potential to be applied to other metropolitan regions, and the resulting peri-urban (and urban) typologies can contribute to a better understanding of the peri-urban character, and to a more targeted implementation of planning and management strategies taking into consideration the diversity and specificities of each peri-urban type.     

Childhood obesity and the income gradient: evidence from Australia

This article examines the dynamic nature of human capital formation in the context of childhood obesity and the association of household income and childhood obesity in Australia using the first five waves of the Longitudinal Study of Australian Children. Our results show a strong evidence of dynamic nature of child obesity: the lag obesity is a significant and robust predictor of obesity in the current period. We also found that the main channel for childhood obesity is inter-generational trait: the probability of obesity in children born to an obese mother or father is 15% higher than that of other children. Other important determinants are lifestyle factors, including the consumption of drinks with a high sugar content and the amount of time watching TV. Income becomes an insignificant determinant of childhood obesity once we control for unobserved individual heterogeneity.