On Measuring the Contribution of OR

Cost-benefit analysis offers a common-sense approach to measuring the contribution of OR but encounters difficulties which have been recognized by Ackoff. Ackoff's concept of adaptivity appears to offer a neat solution to those difficulties but can be seen to provide only a methodology and to lack a background theory. The authors argue that: in general the development of background theory should precede the development of a methodology; for OR the background theory required is one of decision-making; and that the social sciences provide the resource from which an adequate theory of decision-making can be developed.     

On the statistical origins of the learning curve

This paper presents a statistical rationale for the existence of the learning curve phenomenon. We consider a firm which allocates a fixed amount of input into several activities under uncertainty concerning the values of the parameters of the production function. It is shown, under fairly reasonable assumptions, that if the firm learns about the parameters of the production function from previous observations of allocations and outputs, then a learning curve phenomenon will emerge. This result occurs since the estimates of the parameters become more precise over time, and thus the allocation of the production factor into the various activities becomes more efficient (i.e. closer to the optimum allocation that would have been determined if the parameters were known with certainty). Output, therefore, increases and inputs per unit of output decrease as a function of time (and cumulative output), and a learning curve emerges.‘Plateauing’ of the learning curve is discussed, as are the conditions sufficient for the existence of this phenomenon, for which the model presented herein is offered as a possible explanation.     

OR groups and the professionalisation of OR

OR groups have been studied from several perspectives and increasingly their role as a means of organising OR work is seen to be subject to a variety of external influences. In this paper OR groups are examined as a form of arranging professional work in organisations using an analytic framework based on concepts from the sociology of professions. The changing character and fortune of such groups is shown to be related to processes involved with the professional character of OR. The role of education, changing organisational contexts, the emergence of other professions and the ability of OR to respond to these are all key factors in explaining the development of OR groups. Issues of relevance to the future of OR groups arising from this analysis are finally considered.     

On the nature of OR: taking stock

This paper argues that OR, having reached its maturity, must now play to its strengths. In strategic terms this means competing in those areas where OR's core competences can be brought to bear. Using a competence model it is suggested that OR's core products are (i) the development and implementation of the quantitative, algorithmic ‘smart bits’ and (ii) the ‘helpful ways’ of managing intervention processes. These core products are supported and sustained by three core competences labelled process, analytic, and context. Individuals and small groups of practitioners develop ‘strands of practice’ and larger groups ‘webs of practice’ on the basis of their core competences. It is argued that this is giving rise to the emergence of three archetypes of OR service, namely the OR technical consultancy, the OR process consultancy, and the full service OR consultancy. Both the technical and process consulting are built around ‘strands of practice’ of individuals and find their natural home in small service providers. The full service OR consulting practice, in the past located in internal OR groups, will in the future be located within the large management consultancies, which are capable of managing ‘webs of practice’. The implications for the worlds of OR practice and academia are examined.     

On the Nature of OR — Entering the Fray

In 1980 a seminar of operational researchers and practitioners from a variety of different countries concluded that there was a remarkable consensus about the way that the process of operational research and systems analysis should be understood and practised. Since then the development of new methods has continued apace, stimulated by interaction with the social sciences and paradigms other than natural science. This paper enters the debate, started in this journal, about the nature of OR's status as science or technology. It recognizes the historic claims of science on OR, but it suggests that for ‘private’ consumption, technology will prove more fruitful, and for ‘public’ consumption practitioners will increasingly adopt the label ‘consultant’. Ackoff's original six-step method of OR is updated to reflect current OR practice. The process suggested acknowledges the importance of context, socio-political factors and the growing role of facilitation.     

On the roles of OR/MS practitioners in supporting strategy

This paper presents an exploratory account of how Operational Research/Management Science (OR/MS) practitioners understand their role in supporting an organisational strategy process. The role of strategy support is characterised by five dimensions: the activities supported within the strategy process; the nature of support provided; the orientation of the support provided; the tools used in providing support; and the nature of the relationship between consultant and client. The research draws on case studies of four OR/MS practitioners working as internal and as external consultants. The work of the practitioners is mapped onto the framework and gaps are identified. The research proposes a further dimension, namely, ‘the purpose of the support provided’, and suggests four purposeful support roles adopted by practitioners in supporting strategy within organisations: sensemaking/sensegiving; decision support tool development; problem solving/solution exploration; and process facilitation. The paper concludes with suggestions for further research.     

OR and the Social Sciences

The text is the opening address of the conference on OR and the Social Sciences organized by the Operational Research Society, in Cambridge, 10-13 April 1989.     

Supercomputers and OR

This paper presents a literature survey on the use of supercomputers in operational research.     

OR and the management of electronic services

This review paper is meant to provide some insight to the relation between operations research and the management of electronic services. We use the term electronic services, within the broader e-business context, to refer to any service that is delivered to the customer via electronic means, mainly the Internet as a new channel to communicate with customers, but also through mobile and other digital communications. During the last years we have experienced an explosion in the development of electronic services, which is creating abundant opportunities for operations research (OR) applications, required to empower several types of technology-mediated interactions, exploit the large-scale digital data sources, and automate the recurring operational decisions. In this paper we summarise the various aspects in which operations research may support the management of electronic services, taking into account the different characteristics of alternative electronic media, such as the Internet, mobile communications, interactive television etc.     

Justifying the methods of OR

Operational research practitioners use mathematical, statistical, scientific, and other methods to structure and analyse issues in order to advise and assist their clients. In doing so they apply values, follow rules and use methodologies. The paper examines the justification of these methods, values and methodologies. Starting with a conceptual model drawn from the philosophy of science, a justification framework is developed for operational research (OR). Making a distinction between OR academic research and OR practice helps to clarify the issues. OR research is similar to scientific, mathematical and social science research; OR practice, as technology, is closer to engineering. While OR academic researchers will seek justification in the academic discipline within which they choose to work, it is argued that the justification of OR practice lies in its usefulness. For academic OR, justification lies in the justification of mathematics, statistics, science and social science; for practice, it is practitioners who decide what usefulness means in their context.     

On the LASSO and its Dual

Abstract

Proposed by Tibshirani, the least absolute shrinkage and selection operator (LASSO) estimates a vector of regression coefficients by minimizing the residual sum of squares subject to a constraint on the l ¹-norm of the coefficient vector. The LASSO estimator typically has one or more zero elements and thus shares characteristics of both shrinkage estimation and variable selection. In this article we treat the LASSO as a convex programming problem and derive its dual. Consideration of the primal and dual problems together leads to important new insights into the characteristics of the LASSO estimator and to an improved method for estimating its covariance matrix. Using these results we also develop an efficient algorithm for computing LASSO estimates which is usable even in cases where the number of regressors exceeds the number of observations. An S-Plus library based on this algorithm is available from StatLib.     

On the Size of Convoys: An Example of the Methodology of Leading Wartime OR Scientists

The achievements of OR in the Second World War were immense, and yet the teams were without computers and their specialist OR techniques were few and primitive. This brief re-examination of one crucial analysis reveals an approach that diverged substantially from the modern methodology, but was on time and successful, and is of more than historical interest.     

The origins and history of the fields medal

The Fields Medal is the most distinguished unternational award in mathematics. John Charles Fields felt strongly the lack of a Novel Prize in mathematics. He was also disturbed, as Chairman of the Committee of the 1924 International Mathematical Congress, by the scars left from the Versailles Treaty which marred the international character of the Congress. This paper traces the evolution of the award from incidents in Fields' background, through its formal inception at meetings of the University of Toronto Committee fir the 1924 Congress, to its eventual establishment and the first awards at the Oslo International Congress in 1936. Included are a list of all Fields Medal winners to date, the text of Fields' proposal for the establishment of the award, and relevant excerpts from minutes of the Toronto Committee, and a photograph of the medal.     

George Boole and the origins of invariant theory

Historians have repeatedly asserted that invariant theory was born in two papers of George Boole (1841 and 1842). Although several themes and techniques of 19th-century invariant theory are enunciated in this work, in reacting to it (and thereby founding the British school of invariant theory), Arthur Cayley shifted Boole's research program.