Selection of influential variables in ordinal data with preponderance of zeros

Presence of excess zero in ordinal data is pervasive in areas like medical and social sciences. Unfortunately, analysis of such kind of data has so far hardly been looked into, perhaps for the reason that the underlying model that fits such data, is not a generalized linear model. Obviously some methodological developments and intensive computations are required. The current investigation is concerned with the selection of variables in such models. In many occasions where the number of predictors is quite large and some of them are not useful, the maximum likelihood approach is not the automatic choice. As, apart from the messy calculations involved, this approach fails to provide efficient estimates of the underlying parameters. The proposed penalized approach includes ?₁ penalty (LASSO) and the mixture of ?₁ and ?₂ penalties (elastic net). We propose a coordinate descent algorithm to fit a wide class of ordinal regression models and select useful variables appearing in both the ordinal regression and the logistic regression based mixing component. A rigorous discussion on the selection of predictors has been made through a simulation study. The proposed method is illustrated by analyzing the severity of driver injury from Michigan upper peninsula road accidents.     

钢丝网架轻质墙板在房屋墙体工程中的应用

文章结合湖南信托大厦高层框剪结构工程概况,介绍了钢丝网架墙体施工技术的工艺流程,对其施工要点进行了详细阐述,并对该墙体工程进行了经济效益分析。结果表明,该板是理想的轻质节能墙体材料,对取代传统的粘土砖建筑有着积极的作用。     

湖南省煤炭物流发展对策研究

从湖南省煤炭供需现状出发。分析了发展煤炭物流的可行性与必要性,找出了煤炭物流发展存在的一些问题,针对煤炭净调入省份的实际情况,提出了湖南省发展煤炭物流需要整合资源、建立区域煤炭物流中心等对策,以满足经济发展对不断增加的煤炭需求。     

房地产还原利率的构成与测算

从分析投资的风险补偿入手，提出了房地产还原利率的构成和测算公式，同时指出了构成房地产还原利率的银行利率应是复利计算方式下，相应年期的利率，然后探讨了房地产还原利率各构成部分的测算过程，并以中国房地产市场个人住房抵押贷款市场为例，给出了不同收益年限的房地产还原利率参考数据。     

灰色系统理论的财政支出效益研究——以广东省财政支出数据为例

人均收入的增长是度量财政支出效益的指标之一.考察财政支出各项目与人均收入的关系,不仅有利于提高财政支出资金的使用效果,也利于促进财政资源的配置效率,还有利于强化财政管理、完善单位预算管理.通过采用灰色系统理论对广东省城镇和农村2002-2009年的财政支出与人均收入的关系进行灰色关联度分析,得出如下结论:财政支出确实能够促进人民收入的增长;科技支出在促进广东省人均收入增加方面比其他支出的增收作用明显;教育支出对农村的增收作用比城镇大;基础建设在促进农村增收的作用比城镇小.同时提出了通过提高整个财政支出的绩效、加大对农村教育支出的力度并提高教育支出的边际收益率、增加向低收入群体的社会保障支出、提高农村基础建设投入效率并增强农村基础建设的利用率来有效提高广东省居民收入的财政政策建议.     

中国中部六省的碳排放趋势研究

采用王铮等人提出的中国碳排放预估模型,测算在经济平稳增长条件下,中部六省未来的能源碳排放趋势,考虑了6省未来水泥工业的碳排放,并采用CO2FIX模型计算各省森林碳汇量,从而得出各省的净碳排放量,为各省制定碳排放战略提供参考。结果显示：各省的能源碳排放量都呈现先增长后下降的倒U型特征,能源碳排放高峰出现的先后顺序分别是河南、湖南、山西、安徽、江西、湖北;6个省份水泥工业的碳排放都呈现不断增长的趋势,水泥工业产生的碳排放量最大的是河南,最小的是山西;累计森林碳汇量最大的是江西省,其次是湖南省,河南省最小;各省应在减少能源碳排放的同时,控制水泥工业产生的碳排放,积极增加森林碳汇,从多方入手减少碳排放。     

中国省际城镇职工工资收入分布演进的时空特征

运用Kernel密度估计方法和空间马尔科夫链分析方法,并将空间因素纳入分析框架中,对1978—2009年期间中国省际城镇职工工资收入分布演进的时空特征进行了分析。研究结果表明:从时间动态性看,中国省际城镇职工工资收入的差距正逐步固化和深化,多俱乐部收敛特征明显、贫困陷阱问题日益突出;从空间动态性看,近邻效应对省际城镇职工工资收入分布演进存在一定影响,多数省份的工资收入水平向邻区的平均工资收入水平演进。     

Economic structure and factor payments

There is a growing body of evidence that the labour payment share in national income varies across countries and over time, suggesting that the popular aggregate Cobb–Douglas production function may not capture income share dynamics. There remains conflicting evidence on the importance of natural resource rents among low income economies and on estimates of the rate of return to produced capital. This paper focuses on the structural differences among countries, confirming the importance of the agriculture sector in estimates of labour and land’s share of factor income based on 81 countries at diverse levels of economic development in the year 2005. I find that cross-country data are best modelled by a CES production function with an elasticity of substitution of 0.8 and that many low income countries have a higher return to capital than the United States.     

Local Area Inequality and Worker Well-Being

This paper uses General Social Survey data linked to Census data to investigate the effect of local area income and income inequality on worker well-being. Others have found a robust negative correlation between reference group income and self-reported well-being. However, in many cases the reference group is defined as a large geographic area. This paper adds to the literature in two ways. First, it considers multiple nested geographic reference groups with US data. Second, it explicitly considers income inequality in addition to the level of income. It is found that both income and income inequality are positively associated with well-being at the census tract level, but negatively associated at the county level. Further, the effect of inequality on well-being decreases as income increases at the census tract and county level, while it increases at the state level.     

The Dilemmas of Technology: A Review Article

During the 1990s, all of the European transition economies (TE) experienced a major recession and suffered from the explosion of income inequality. However, distribution of income between labor and capital differed greatly from one group of post-communist countries to another. The paper discusses and analyzes linkages between models of capitalism that emerged in former communist countries in the 1990s and the outcome of capitalist transition for labor in terms of income distribution and inequality. It is based on the estimates of the Marxian rate of exploitation and other indicators of labor income performance during the reform period.