The Effect of Sample Size on the Mean Efficiency in DEA with an Application to Electricity Distribution in Australia,Sweden and New Zealand

This study examines the effect of sample size on the mean productive efficiency of firms when the efficiency is evaluated using the non-parametric approach of Data Envelopment Analysis. By employing Monte Carlo simulation, we show how the mean efficiency is related to the sample size. The paper discusses the implications for international comparisons. As an application, we investigate the efficiency of the electricity distribution industries in Australia, Sweden and New Zealand.     

对管理会计方法的几点质疑

管理会计学科知识中涉及到大量的分析模型和数据指标，在现实生活中往往被人们不加推敲地生搬硬套，视其为当然的权威、绝对地正确，使管理会计的学习应用趋于教条化。而实际上，管理会计还是一门发展并不十分成熟的学科，其中存在许多值得我们进一步研究和论证的问题。例如，有些方法已明显与现实脱节，有些方法还停留在以静止的观点看问题。有的不考虑管理会计这一信息系统中数据信息的取得成本，有的分析模型一味追求精确复杂反而推动了实际应用价值，有的分析方法干脆就不具备多少严谨性和可信性。本文针对以上问题进行了讨论，旨在抛砖引玉，使管理会计这一学科更加健全和完善。     

Technology gaps in European banking: Put the blame on inputs or outputs?

This paper investigates the production efficiency of 12 European banking systems over the period 1997–2004, taking into account possible technology heterogeneity. Using a non-parametric metafrontier framework, efficiency and metatechnology ratio measures are computed and decomposed into input- and output-invariant components. Empirical findings indicate the existence of significant and rather increasing technology heterogeneity within European banking. A typology of the national banking systems is also developed, based on the overall productive performance with respect to the European technological edge, the absorptive capacity and the role of knowledge spillover effects. Decomposition results draw attention to catching up policies focusing on input and/or output scale adjustments.     

Testing population variance in case of one sample and the difference of variances in case of two samples: Example of wage and pension data sets in Serbia

Testing one population variance and the difference in variances of two populations based on the ordinary t-statistics combined with the bootstrap method are suggested in this article. Suggested techniques are combined with Hall's transformation approach. Application of presented methods in domain of real economic data set is described and analyzed. We compare the outputs of suggested methods and traditional methods for considered data set. The results show that these introduced methods have small advantages in comparisons with traditional methods especially for small samples.     

网络系统并行数据库中数据均衡分配方案的探讨

介绍了网络并行机群的特点以及目前并行机系统新的发展趋势,分析了网络并行机群环境下，并行数据库数据分布中数据倾斜问题的特点，提出了一种具有适应环境能力的动态数据均衡分配方案。     

Evaluating the efficiency and productivity change within government subsidy recipients of a national technology innovation research and development program

This study analyzes the efficiency and productivity change within government subsidy recipients of a national technology innovation research and development (R&D) program. We examine 6,990 government‐sponsored, completed R&D projects during the last three performance follow‐up survey years from 2010 to 2012, and present a design of the sample of panel data to cope with the typical R&D performance time lag using a set of massive observations associated with completed R&D projects for the past 7 years from 2005 to 2011. In particular, data envelopment analysis is adopted to measure the efficiency and productivity change, which is measured in the Malmquist index. Parametric and nonparametric statistical tests are carried out to check for statistically significant differences among the characteristics regarding the types of government subsidy recipients. This study's major findings are as follows. First, during the entire period analyzed (2010–2012), there was a similar yearly pattern of statistically significant differences in the government subsidy means among the recipient types. In contrast, there were no obviously equivalent differences in the efficiency and productivity change. Second, the productivity had increased year on year, but the increments were reduced from year to year. Third, the productivity change was induced mainly by the Frontier‐shift, which indicates overall technology innovation progress, compared with the Catch‐up, which only indicates a simple increase in the efficiency. In particular, in this empirical analysis, the recipient types of ‘national laboratory’ and ‘large company’ had relatively larger sizes of government subsidies per project. However, the efficiency and productivity change of these types was not better than the others. This implies, therefore, that the government should control the ratio of the subsidy to the total R&D budget with an appropriate upper limit.

• I empirically evaluate the productivity change within a national technology innovation R&D program.
• I design a sample of panel data to cope with the typical R&D performance time lag using massive observations.
• There is no obvious relationship between the government subsidy size and R&D productivity change.
• Some particular types of government subsidy recipient are inferior in terms of R&D productivity change.
• It practically implies that the government should control the ratio of the subsidy to the total R&D budget.

     

DM技术及其在数据处理中的应用

简要介绍了DM(数据挖掘 )及其工作过程 ,并指出了数据挖掘过程中应注意的问题 ,最后给出了一个具体的数据挖掘的例子     

Customer relationship management in retailing: A content analysis of retail trade journals

The purpose of this research was to increase knowledge and understanding of how retailers use business intelligence and data mining tools to implement customer relationship management (CRM) in retailing. Specific objectives were to (1) identify organization and infrastructure requirements for CRM effectiveness, (2) identify CRM objectives and goals of retail companies, (3) identify data mining tools utilized by retailers to perform CRM functions, and (4) identify CRM strategies used by retail companies. A keyword search within business databases using CRM and CRM identified publications with CRM content. Content analysis was used on articles (N=149) drawn from Stores, Chain Store Age, Harvard Business Review, and Retail Forward over a 5 year period (2000–2005). Selected articles were stored as text files in QDA Miner, a computerized qualitative analysis tool. Key organization/infrastructure needs emerged focusing on data structure, organizational systems, technology structure, and data accessibility. Retailers goals/objectives and strategies focused on marketing, customer service, understanding customers through data analysis and increasing acquisition and retention through customer loyalty programs. Data mining tools identified supported marketing and customer analysis efforts. Findings provide insight into the challenges retailers face as they implement a more customer-centric business strategy.     

Incorporating satisfaction measures into a restaurant productivity index

The increasing stature of the foodservice industry in the global service economy suggests that productivity analyses—similar to those performed in non-service-based settings—would benefit multi-unit operators by maximizing their desirable operational outcomes while minimizing expenses and other detrimental conditions such as low job satisfaction. This paper suggests that such analyses might be possible through the application of a holistic productivity metric—one that includes traditional operational variables such as revenue, profit, food cost, and labor cost, and previously ignored variables such as guest and employee satisfaction as well as retention equity. Through data gathered from a single chain's 36 corporate-owned, same-brand casual-theme restaurants located in metropolitan centers across the United States, we found that factors leading to maximum outputs such as controllable profit and retention equity include employee satisfaction in addition to expected variables such as cost of goods sold and number of seats. Most notably, employee satisfaction as an input proved to be the most volatile variable in maximizing operational outputs.     

LZW压缩数据的不均一两分段误码保护编码

由T.A.Welch提出的LZW数据压缩方法已经被广泛地应用于文字压缩。然而，因为误码对压缩数据的危害很大，所以对压缩数据的纠错编码是十分重要且必不可少的。本文分析了误码对LZW压缩数据的影响，指出同样的误码对用于重建辞书的前一部分压缩数据的危害比对后面的其它数据的危害要严重得多，提出用一种不均一两分段误码保护编码方法，对用于重建辞书的前一部分压缩数据进行更好地保护。计算机模拟显示，该方法比传统的误码保护方法更有效。