Productivity differences across OECD countries in the presence of environmental constraints

The purpose of this paper is to carry out a computational analysis of the tradeoffs between a good output and the CO₂ emissions or bad output that is often created as a by-product of the production process. The efficiency of this process is computed through a series of DEA formulations, related to the two outputs. One formulation considers the strategy of minimizing the pollution level produced for the generation of a given good-output level. Another seeks the maximum good-output production for a set bad-output level. A mixed strategy looks for simultaneous increases in the good output and decreases in CO₂ emissions. A fourth ignores altogether the presence of the bad output. The empirical analysis illustrates the feasibility of achieving productivity growth and pollution decreases. It also identifies country trends for the 1970–1990 period in the production of good and bad outputs of 14 OECD countries. These trends resemble quite closely the strategies described in the paper.     

Measuring sectoral productivity across time and across countries

This paper examines the problem of measuring the evolution of productivity changes over time and across the 14 countries included in the OECD's International Sectoral Data Base of two sectors considered essential to the economic growth of any nation, namely manufacturing and services. The basic units of analysis are generalized Malmquist productivity indices. These in turn can be decomposed into several components, associated to the various sources of productivity change. Included here are productivity fluctuations due to economies of scale, being constant or variable, to technical change and technical efficiency change. The computational procedure is based upon the concept of distance function, computed through the use of variations of data envelopment analysis.     

战略性新兴产业典型国家的产业发展对比研究

以战略性新兴产业领域发展较好的世界典型国家为研究对象,与中国七个战略性新兴产业发展现状进行一一对比分析.结果表明:(1)美国占据节能环保产业的生产和消费绝对优势,中国的节能环保产业市场规模相比显得幼小;(2)全球新一代信息技术产业的主要市场份额由美国、欧盟占据,但中国对该产业的国内市场需求发展迅速;(3)全球生物医药产业呈现集群化发展态势,美国、欧洲、日本拥有世界94%的专利,中国的技术研发薄弱;(4)美国、加拿大、欧洲、俄罗斯的高端装备制造业在全球处于全面领先地位,中国的该产业在市场和技术上紧追发达国家;(5)美国、日本、德国、俄罗斯的新材料产业技术处于全球领先地位,中国、印度和巴西的迅速发展;(6)新能源产业方面以光伏为主,中国光伏装机规模最大,北美、欧洲、日本出口市场放缓,中国仍然存在产能过剩风险;(7)中国、美国、欧洲新能源汽车销售增长率最快,中国新能源汽车自主使用率高,但对政府补贴的依赖很严重.针对上述分析结果,结合中国战略性新兴产业发展存在的实际问题,提出了相应的对策建议.     

Assessment of teacher knowledge across countries: a review of the state of research

This review presents an overview of research on the assessment of mathematics teachers’ knowledge as one of the most important parameters of the quality of mathematics teaching in school. Its focus is on comparative and international studies that allow for analyzing the cultural dimensions of teacher knowledge. First, important conceptual frameworks underlying comparative studies of mathematics teachers’ knowledge are summarized. Then, key instruments designed to assess the content knowledge and pedagogical content knowledge of future and practicing mathematics teachers in different countries are described. Core results from comparative and international studies are documented, including what we know about factors influencing the development of teacher knowledge and how the knowledge is related to teacher performance and student achievement. Finally, we discuss the challenges connected to cross-country assessments of teacher knowledge and we point to future research prospects.     

The impact of information technology on the banking industry

This paper analyses the effects of investment in information technologies (IT) in the banking sector using bank-level data from a panel of 68 US banks over the period 1986–2005. Although IT can improve bank's performance by reducing operational cost (supply side), it can bring in competition among banks in order to embrace new technology (demand side). Since most empirical studies have adopted the production function approach, it is difficult to identify which effect has dominated. In a differentiated model with network effects, this paper characterizes the conditions to identify these two effects. The results suggest that (at individual firm levels) the bank profits can decline due to adoption and diffusion of IT investment, reflecting negative network competition effects in this industry. Using panel cointegration tests, we confirm that the estimated profit equation is indeed a long-run equilibrium relation.     

Opportunity to learn in the preparation of mathematics teachers: its structure and how it varies across six countries

Cross-national research studies such as the Program for International Student Assessment and the Third International Mathematics and Science Study (TIMSS) have contributed much to our understandings regarding country differences in student achievement in mathematics, especially at the primary (elementary) and lower secondary (middle school) levels. TIMSS, especially, has demonstrated the central role that the concept of opportunity to learn plays in understanding cross-national differences in achievement Schmidt et al., (Why schools matter: A cross-national comparison of curriculum and learning  2001). The curricular expectations of a nation and the actual content exposure that is delivered to students by teachers were found to be among the most salient features of schooling related to academic performance. The other feature that emerges in these studies is the importance of the teacher. The professional competence of the teacher which includes substantive knowledge regarding formal mathematics, mathematics pedagogy and general pedagogy is suggested as being significant—not just in understanding cross-national differences but also in other studies as well (Hill et al. in Am Educ Res J 42(2):371–406, 2005). Mathematics Teaching in the 21st Century (MT21) is a small, six-country study that collected data on future lower secondary teachers in their last year of preparation. One of the findings noted in the first report of that study was that the opportunities future teachers experienced as part of their formal education varied across the six countries (Schmidt et al. in The preparation gap: Teacher education for middle school mathematics in six countries, 2007). This variation in opportunity to learn (OTL) existed in course work related to formal mathematics, mathematics pedagogy and general pedagogy. It appears from these initial results that OTL not only is important in understanding K-12 student learning but it is also likely important in understanding the knowledge base of the teachers who teach them which then has the potential to influence student learning as well. This study using the same MT21 data examines in greater detail the configuration of the educational opportunities future teachers had during their teacher education in some 34 institutions across the six countries.     

The transfer of systems technology: logistics systems for underdeveloped countries

New approaches to large scale industrial development in less developed countries require closer attention to the design of the support systems needed to keep the plants running after construction. System redundancy, loose coupling of subsystems and the capability for adaptive learning become particularly important design principles given the complexity of the operating environment. This paper discusses the application of these principles to logistics systems design for a multibillion dollar steel plant. Specific guidelines are developed for the requisitioning process for spare parts and materials, for item identification, for the use of assemblies and for the organization of storage and retrieval procedures.     

A dialectical framework for problem structuring and information technology

This paper proposes that problem structuring is characterized by dialectical processes, and that different problem situations call for differing emphasis on the organizing versus disorganizing potential of information technologies. The term ‘dialectical’ emphasizes the conflicting forces of structuring and unstructuring in processes of problem solving. A case study of an enterprise software conversion project examines four processes: structuring, unstructuring, groping, and adjusting. Applying the dialectic perspective to the classic Gorry and Scott-Morton framework yields propositions as to which of these four processes should be emphasized by information systems addressing different types of problems. Implications for the design of decision support systems and for future research are discussed.     

Investigating and comparing the dynamic patterns of the business value of information technology over time

The long-debated issue of the business value of information technology (IT) to the firm (country) has received a great deal of attention in the literature. But the studies have rarely examined the dynamic patterns of the IT value as measured by the firm’s productive efficiency over time. The objective of this paper is to apply the three-factor constant elasticity of substitution (CES) time-varying stochastic production frontier models and use the same data set as used in several previous studies to investigate the dynamic patterns of IT value over time in connection with the issues of inputs substitution and complement and the productivity paradox. This paper adopts two analytical skills, collective and individual, to analyze the empirical results. Collectively, we find that the dynamic patterns of IT value are closely related to the substitution and complement of three inputs and the IT productivity paradox. Individually, we identify five common dynamic patterns of the IT value measured by productive efficiency and interpret their implications for the productivity paradox as summarized in a two by two matrix of practical applications and strategies. This matrix accounts for four different scenarios of the relationship between the average productive efficiency and the IT productivity paradox, illustrates some practical applications by the analytical results, and provides some business insights and managerial strategies for IT decision makers and PO/IS managers. This represents a new contribution to the understanding of the dynamic influence of IT investments upon the value of IT over time.     

A study on the modeling ability of the IDS method: A soft computing technique using pattern-based information processing

The ink drop spread (IDS) method is a modeling technique developed by algorithmically mimicking the information-handling processes of the human brain. This method has been proposed as a new approach to soft computing. IDS modeling is characterized by processing that uses intuitive pattern information instead of complex formulas, and it is capable of stable and fast convergences. This paper investigates the modeling ability of the IDS method based on three typical benchmarks. Experimental results demonstrated that the IDS method can handle various modeling targets, ranging from logic operations to complex nonlinear systems, and that its modeling performance is satisfactory in comparison with that of feedforward neural networks.     

A multicriteria accreditation system for information technology skills and qualifications

Employees must acquire new competences and qualifications throughout their lives, in order to be able to deal with the multiple changes in the labour market. The specific knowledge and competences, acquired either formally or non-formally, must be recognized so that they can be transferred and utilized. The existing titles of studies and accreditation mechanisms do not generally cover this need. This paper aims to propose an integrated approach for the evaluation of information technology knowledge and skills, regardless of where and how they have been acquired, so as to apply a continuous education and training policy. The proposed multicriteria methodology for the evaluation of qualifications and skills concerns candidates wishing to be accredited in an information technology specialization or profession. The methodology refers to the evaluation of the professional experience, studies and vocational training of the candidates for accreditation. It contains the analysis and modelling of the qualitative criteria as well as the implementation of multicriteria aggregation–disaggregation techniques attributing value to each criterion. Then, the candidates are classified in categories of professionals using the Electre Tri method, accepting as input data the multicriteria assessments on each criterion. The proposed evaluation approach has been adapted to the Greek educational system and is applied to a specific example of candidate.     

In search of information technology productivity: Assessment issues

Despite the massive investments in Information Technology (IT) in the developed economies, the IT impact on productivity and business performance continues to be questioned. The paper critically reviews this ‘IT productivity paradox’ debate. It suggests that important elements in the uncertainty about the IT payoff relate to deficiencies in measurement at the macroeconomic level, but also to weaknesses in organisational evaluation practice. The paper reports evidence from a 1996 UK survey pointing to such weaknesses. Focusing at the more meaningful organisational level, an integrated systems lifecycle approach is put forward as a long term way of strengthening evaluation practice. This incorporates a cultural change in evaluation from ‘control through numbers’ to a focus on quality improvement. The approach is compared against 1995–96 research findings in a multinational insurance company, where senior managers in a newly created business division consciously sought related improvements in evaluation practice, and IT productivity.     

On the breakdown of perturbation theory

The production of particles in a weakly-coupled theory is believed to be non-perturbatively suppressed. I comment on the prospects of (a) establishing this rigorously, and (b) estimating the effect to exponential accuracy semiclassically, by discussing two closely-related problems: the large-order behavior of few-point Green functions, and induced excitation in quantum mechanics. Induced tunneling in the latter case is exponentially enhanced for frequencies of the order of the barrier height.Published in Teoreticheskaya i Matematicheskaya Fizika, Vol. 95, No. 2, pp. 187–196, May, 1993.     

Problem of the breakdown of polymer materials

The kinetic dependence of the strength characteristics of polymers is examined in relation to the specific characteristic features of their structure. The interrelationship of the process of breakdown to relaxation transitions in the polymers and to factors influencing the temperature characteristics of the transitions has been demonstrated.     

On the complexity of computing treelength

We resolve the computational complexity of determining the treelength of a graph, thereby solving an open problem of Dourisboure and Gavoille, who introduced this parameter, and asked to determine the complexity of recognizing graphs of a bounded treelength Dourisboure and Gavoille (2007) [6]. While recognizing graphs with treelength 1 is easily seen as equivalent to recognizing chordal graphs, which can be done in linear time, the computational complexity of recognizing graphs with treelength 2 was unknown until this result. We show that the problem of determining whether a given graph has a treelength at most k is NP-complete for every fixed k≥2, and use this result to show that treelength in weighted graphs is hard to approximate within a factor smaller than . Additionally, we show that treelength can be computed in time O^∗(1.7549ⁿ) by giving an exact exponential time algorithm for the Chordal Sandwich problem and showing how this algorithm can be used to compute the treelength of a graph.     

On computing the entropy of braids

We consider the problem of computing the entropy of a braid. We recall its definition and for each braid construct a sequence of real numbers whose limit is the braid’s entropy. We state one conjecture on the convergence speed and two conjectures on braids that have high entropy but are written with few letters.