Productivity breakdown of the information and computing technology industries across countries

In this paper, we measure productivity growth of the information and computing technology (ICT) industries in 14 Organization for Economic Cooperation and Development countries over the 13-year period of 1978–1990. The ICT industries are the providers of essential information technology (IT) capital goods. This macro-level analysis seeks to find out how productively such IT capital goods are provided. The basic unit of analysis employed is the Malmquist Total Factor Productivity (TFP) index. The Malmquist TFP index is then decomposed into three constituent elements accounting for different sources of productivity growth: technological progress, efficiency change, and change in economies of scale. The approach of measurement is based on the concept of distance functions and employs the non-parametric frontier method of data envelopment analysis. Our results indicate that each country's ICT industry manifests its own particular patterns in various performance measures. Among the 14 countries examined, 10 had witnessed productivity growth in their ICT industries. Overall, these ICT industries are found more productive than other industries when compared with previous research. Further analyses reveal that (1) most of the productivity growth measured is due to technological progress; (2) efficiency change exerts a relatively small positive effect on productivity growth; and (3) the change in scale economies unfavourably affects productivity for most countries. Finally, practical implications for formulating IT policy are drawn from our results, and topics are identified for future research.     

Age replacement in the presence of inventory constraints

Many authors in the literature have treated the age replacement problem and its various modifications. One generally is asked to assume the ability of a system to provide instantaneous replacements whenever needed. This is often not a very realistic assumption. In this paper we will examine one recent age replacement model when replacements are constrained by two simple inventory models.     

Asset allocation strategies in the presence of liability constraints

The performance of portfolio managers is usually assessed by comparing their allocation strategies to a benchmark portfolio. A major issue for portfolio managers of liability driven institutions is that no benchmark is given to them, although they face mid-term objectives with short term constraints. No performance attribution methodology may then be used to serve as a reference. Assessing the performance of the asset manager as an agent, represents a major stake for the institution as a principal delegating a mandate of asset management. We propose an optimal asset allocation approach taking into account liability constraints to build a benchmark. This benchmark will be used to compare the ex-post effective performance of the asset manager to the effective performance of the ex-ante optimal dynamic asset allocation.     

Pareto-optimal reinsurance policies in the presence of individual risk constraints

Annals of Operations Research - The notion of Pareto optimality is commonly employed to formulate decisions that reconcile the conflicting interests of multiple agents with possibly different risk...     

Statistics of a polymer chain in the presence of random topological constraints

Tomsk State Pedagogical Institute; Scientific-Research Institute of the Iron Industry of the Ministry of Chemical and Oil Refining Industry of the USSR. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 86, No. 3, pp. 344–352, March, 1991.     

Linear differential pursuit games with integral constraints in the presence of delay

Problems involving linear differential pursuit games were studied by many authors; their work served as a basis for studying pursuit problems in linear differential games with integral constraints. In the present paper, we obtain sufficient conditions for the solvability of linear pursuit problems with integral constraints on the control of the players in the presence of delay.     

Optimal solutions to differential inclusions in presence of state constraints

Necessary conditions in terms of the Hamiltonian are given for optimal solutions to the differential inclusion problem when state constraints are present. This result extends a result of Clarke for the unconstrained problem. The data are nonsmooth, nonlinear, nonconvex. The method incorporates the state constraint in the cost functional as a penalty term for a sequence of unconstrained problems that approximate our problem. An application of Ekeland's variational principle, the known necessary conditions for the auxiliary problems, and a limiting process provide the necessary conditions.     

Network DEA efficiency in input–output models: With an application to OECD countries

We undertake network efficiency analysis within an input–output model that allows us to assess potential technical efficiency gains by comparing technologies corresponding to different economies. Input–output tables represent a network where different sectoral nodes use primary inputs (endowments) to produce intermediate input and outputs (according to sectoral technologies), and satisfy final demand (preferences). Within the input–output framework it is possible to optimize primary inputs allocation, intermediate production and final demand production by way of non-parametric data envelopment analysis (DEA) techniques. DEA allows us to model the different subtechnologies corresponding to alternative production processes, to assess efficient resource allocation among them, and to determine potential output gains if inefficiencies were dealt with. The proposed model optimizes the underlying multi-stage technologies that the input–output system comprises identifying the best practice economies. The model is applied to a set of OECD countries.     

Optimal separation of a specified harmonic using feedback in the presence of phase constraints

The Pontryagin maximum principle is applied to solve the problem of minimizing the deviation of the state of a parabolic system from a specified harmonic while keeping constant the sum of Fourier coefficients (phase coordinates). Translated from Algoritmy Upravleniya i Identifikatsii, pp. 77–84, 1997.     

Assessing efficiency of public health and medical care provision in OECD countries after a decade of reform

Central European Journal of Operations Research - The objective of this study was to examine the change in efficiency of health care systems of 34 OECD countries between 2000 and 2012, a period...     

Sufficient optimality criteria in non-linear programming in the presence of convex equality and inequality constraints

Summary Sufficient optimality criteria are derived for mathematical programs in which non-linear inequality and equality constraints are present. These are similar to those ofKuhn-Tucker andFritz John optimality criteria.

---

Zusammenfassung Für mathematische Optimierungsprobleme mit nichtlinearen Nebenbedingungen in Ungleichungs- und Gleichungsform werden hinreichende Optimalitätskriterien entwickelt, die denen vonKuhn-Tucker undFritz John gleichen.

     

An iterative algorithm for estimation of signals from analytical instruments in the presence of constraints

Translated from Pryamye i Obratnye Zadachi Matematicheskoi Fiziki, pp. 45–48, 1991.     

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.     

Total factor productivity growth and directions of technical change bias: evidence from 99 OECD and non-OECD countries

Based on data of 99 nations during 1991–2003, the Malmquist index and its composition of technical change and efficiency change are estimated. In particular, the hypothesis of neutral technology is released to divide technology into the magnitude of the shift in the world production frontier and input-biased technology, and to show that in order to gain more benefit or not to lose so much benefit from technology change, it is important for countries to coordinate their choice of input mix with the directions of technology bias if their technical changes are biased. The results indicate that both OECD and non-OECD countries tend to show capital-using/labor-saving, capital-using/energy-saving and energy-using/labor-saving technical change bias over the entire period. The production pattern of a majority of countries is shown to have been able to take advantage of their technological innovations.     

Collisionless diffusion of particles across a magnetic field at a plasma edge in the presence of turbulence

We study the collisionless diffusion of electrons and ions across a magnetic field at a plasma edge, in the turbulent field produced by a Kelvin–Helmholtz instability. Ions and electrons are described by gyro-kinetic equations which include the finite Larmor radius correction and the polarization drift. Characteristic methods associated with cubic spline interpolation in two dimensions (2D) are used to integrate the gyro-kinetic equations in a slab geometry.     

Learning from similarities and differences: a reflection on the potentials and constraints of cross-national studies in mathematics

Research in mathematics education that crosses national boundaries provides new insights into the development and improvement of the teaching and learning of mathematics. In particular, cross-national comparisons lead researchers to more explicit understanding of their own implicit theories about how teachers teach and how children learn mathematics in their local contexts as well as what is going on in school mathematics in other countries. Further, when researchers from multiple countries and regions study collaboratively aspects of teaching and learning of mathematics, the taken-for-granted familiar practices in the classroom can be questioned. Such cross-national comparisons provide opportunities for researchers and educators to probe typical dichotomies such as “high-performing” versus “low performing”, “teacher-centred versus student-centred”, or even “East versus West”, in searching for similarities and differences in educational policies and practices in different cultural contexts.