Online hierarchical forecasting for power consumption data

This paper proposes a three-step approach to forecasting time series of electricity consumption at different levels of household aggregation. These series are linked by hierarchical constraints—global consumption is the sum of regional consumption, for example. First, benchmark forecasts are generated for all series using generalized additive models. Second, for each series, the aggregation algorithm ML-Poly, introduced by Gaillard, Stoltz, and van Erven in 2014, finds an optimal linear combination of the benchmarks. Finally, the forecasts are projected onto a coherent subspace to ensure that the final forecasts satisfy the hierarchical constraints. By minimizing a regret criterion, we show that the aggregation and projection steps improve the root mean square error of the forecasts. Our approach is tested on household electricity consumption data; experimental results suggest that successive aggregation and projection steps improve the benchmark forecasts at different levels of household aggregation.     

Enterprise system implementation issues: learning from field study in Poland

This study examines enterprise system (ES) implementation issues on the basis of research conducted among practitioners dealing with ES projects in Poland. The particular topics investigated include mechanisms determining the success of ES implementations, project conditions and implementation effects. Using a success factors model and a synthetic measure of implementation success, this paper recognises the factors that have the greatest influence on implementation success. While researching project conditions, this study discusses how the ES projects researched were linked with enterprise strategy, how their efficiency was measured and to what extent they defined implementation goals. This paper analyses also the positive and negative effects of ES implementations. The effects investigated were divided into technical, economic, organisational and social results. During the analysis, the implementations examined were divided into groups of projects on the basis of their duration, scope and company size. The findings recognise the leading roles of certain factors among specific project groups and suggest that participants from the most complicated projects are most aware of the overwhelming implementation challenge. The analysis reveals some differences in perceptions and attitudes between stakeholders involved in an implementation project. Managerial and research issues are discussed, together with country-specific aspects.     

Public ownership of banks and economic growth

In an influential article, La Porta et al. (2002) argue that public ownership of banks is associated with lower GDP growth. We show that this relationship does not hold for all countries, but depends on a country's initial conditions, in particular its financial development and political institutions. Public ownership is harmful only if a country has low financial development and low institutional quality. The negative impact of public ownership on growth fades quickly as the financial and political system develops. In highly developed countries, we find no or even positive effects. Policy conclusions for individual countries are likely to be misleading if such heterogeneity is ignored.     

浅析煤矿物资经营管理的问题及解决对策

加强煤炭企业的物资管理,对于企业产品生产成本的降低,企业经济效益的增加有极其重要的意义。现代的煤矿企业要想实现规范的、科学的、合理的物资管理系统,首先必须要有良好的物资管理流程,同时,还要抓好物资的计划与采购。利用现代化的信息手段实现煤炭企业物资问题的科学管理。     

试论居住区景观设计的几点问题

人民生活水平的日益提高,绿色生态住宅小区成为每个城市人的梦想。人们越来越注重自身的生活环境,但是在小区环境的营造中也存在着一些问题。     

类似条件下工程变更项目综合单价确定研究

工程施工期间工程变更的发生具有不可回避的特点,对于工程变更价款的有效确定,关键在于准确分析变更项目综合单价的组成以及所属类型。为了解决类似条件下变更项目综合单价的确定问题,文章从界定类似条件下变更项目综合单价的定价适用内容出发,对变更项目综合单价的确定过程展开研究,最终提出材料改变情况下变更工程综合单价的确定方法。     

试论湖南局第三产业的现状及发展

文章对湖南地勘局第三产业现状及存在的问题进行了分析,进而提出了加强三产发展的4条措施.     

论广告要约的隐含条件

广告的特点决定了其中不确定因素太多,作为要约容易引起争议.但是,在广告内容非常明确、肯定,足以构成一项要约时,合理地理解其中的隐含条件,不仅符合人们日常对广告的理解,也更有利于公平处理当事人之间的关系.     

老年社区的市场需求特征及启示研究——以长三角地区为例

随着我国老龄化问题的凸现,传统的养老观念和养老模式正在发生深刻的改变,老年社区的市场需求日益增长。本文运用数理统计方法,以长三角地区为例对选择老年社区的老年人养老和居住需求进行研究。据此探讨老年社区的市场需求特征,分析未来老年人养老和居住需求的发展趋势,并对老年社区建设提出相应的开发对策和建议。     

Comparing working conditions and job satisfaction in hospitality workers across Europe

Job satisfaction is important in the tourism sector since workers’ satisfaction is key to providing high-quality service, which is very important in determining organizational success. The working conditions that influence job satisfaction depend to a large extent on the institutional context, which shows similarities in some European countries. This research aims to compare working conditions and job satisfaction among European country blocks that have similar institutional characteristics. Unlike previous studies, this research adopts a comprehensive approach by considering institutional and organizational factors in the analysis of employees’ perceptions of job satisfaction. The sample is made up of 1633 workers in 16 European countries. The results demonstrate the existence of three different models of working conditions in Europe leading to differing levels of job satisfaction in tourism. These models do not correspond to the clusters identified by the previous literature, which adopts an institutional perspective.