Understanding problem structuring methods interventions

This article presents a conceptual framework and methodological guide for researching and understanding OR interventions particularly problem structuring methods (PSM). The article argues that OR/PSM interventions are complex events which can not be understood by traditional approaches alone. In this paper an alternative methodology is developed, where the units of analysis are the narratives and networks produced during PSM interventions. The paper outlines the main theoretical and methodological concerns that need to be appreciated in studying PSM interventions. The paper then explores actor-network theory and narrative analysis as approaches to study them. A case study describing the use of these approaches is provided.     

Problem structuring methods: theorizing the benefits of deconstructing sustainable development projects

Problem structuring methods or PSMs are widely applied across a range of variable but generally small-scale organizational contexts. However, it has been argued that they are seen and experienced less often in areas of wide ranging and highly complex human activity—specifically those relating to sustainability, environment, democracy and conflict (or SEDC). In an attempt to plan, track and influence human activity in SEDC contexts, the authors in this paper make the theoretical case for a PSM, derived from various existing approaches. They show how it could make a contribution in a specific practical context—within sustainable coastal development projects around the Mediterranean which have utilized systemic and prospective sustainability analysis or, as it is now known, Imagine. The latter is itself a PSM but one which is ‘bounded’ within the limits of the project to help deliver the required ‘deliverables’ set out in the project blueprint. The authors argue that sustainable development projects would benefit from a deconstruction of process by those engaged in the project and suggest one approach that could be taken—a breakout from a project-bounded PSM to an analysis that embraces the project itself. The paper begins with an introduction to the sustainable development context and literature and then goes on to illustrate the issues by grounding the debate within a set of projects facilitated by Blue Plan for Mediterranean coastal zones. The paper goes on to show how the analytical framework could be applied and what insights might be generated.     

Problem structuring methods ‘in the Dock’: Arguing the case for Soft OR

Problem structuring methods (‘soft’ OR) have been around for approximately 40 years and yet these methods are still very much overlooked in the OR world. Whilst there is almost certainly a number of explanations for this, two key stumbling blocks are: (1) the subjective nature of the modelling yielding insights rather than testable results, and (2) the demand on users to both manage content (through modelling) and processes (work with rather than ‘on behalf’ of groups). However, as evidenced from practice there are also a number of significant benefits. This paper therefore aims to examine the case of Soft OR through examining the case for and against problem structuring methods.     

Problem structuring using computer-aided morphological analysis

General morphological analysis (GMA) is a method for structuring and investigating the total set of relationships contained in multidimensional, usually non-quantifiable, problem complexes. Pioneered by Fritz Zwicky at the California Institute of Technology in the 1930s and 1940s, it relies on a constructed parameter space, linked by way of logical relationships, rather than on causal relationships and a hierarchal structure. During the past 10 years, GMA has been computerized and extended for structuring and analysing complex policy spaces, developing futures scenarios and modelling strategy alternatives. This article gives a historical and theoretical background to GMA as a problem structuring method, compares it with a number of other ‘soft-OR’ methods, and presents a recent application in structuring a complex policy issue. The issue involves the development of an extended producer responsibility (EPR) system in Sweden.     

Towards a new framework for evaluating systemic problem structuring methods

Operational researchers and social scientists often make significant claims for the value of systemic problem structuring and other participative methods. However, when they present evidence to support these claims, it is usually based on single case studies of intervention. There have been very few attempts at evaluating across methods and across interventions undertaken by different people. This is because, in any local intervention, contextual factors, the skills of the researcher and the purposes being pursued by stakeholders affect the perceived success or failure of a method. The use of standard criteria for comparing methods is therefore made problematic by the need to consider what is unique in each intervention. So, is it possible to develop a single evaluation approach that can support both locally meaningful evaluations and longer-term comparisons between methods? This paper outlines a methodological framework for the evaluation of systemic problem structuring methods that seeks to do just this.     

Approaches to sharing knowledge in group problem structuring

Problem-structuring techniques are an integral aspect of ‘Soft-OR’. SSM, SAST, Strategic Choice, and JOURNEY Making, all depend for their success on a group developing a shared view of a problem through some form of explicit modelling. The negotiated problem structure becomes the basis for problem resolution. Implicit to this process is an assumption that members of the group share and build their knowledge about the problem domain. This paper explores the extent to which this assumption is reasonable. The research is based on detailed records from the use of JOURNEY Making, where it has used special purpose Group Support software to aid the group problem structuring. This software continuously tracks the contributions of each member of the group and thus the extent to which they appear to be ‘connecting’ and augmenting their own knowledge with that of other members of the group. Software records of problem resolution in real organisational settings are used to explore the sharing of knowledge among senior managers. These explorations suggest a typology of knowledge sharing. The implications of this typology for problem structuring and an agenda for future research are considered.     

Size matters: large group methods and the process of operational research

This paper will briefly outline some of the reasons for the burgeoning interest in working with the widest range of individuals in an organisation. The paper will explore the emergence of methods and processes to tackle large group work. It will then go on to describe, via case studies, a few methods that have been used in large-scale interventions. The paper will end with some reflections on working with large groups and explore some proposals for the process of OR.     

Past,present and future of problem structuring methods

To be able to exploit the future opportunities for Operational Research (OR), we need to prepare for them now. To conceptualize alternative futures for OR, we need to understand the potentialities of the present. To understand the present, we need to have a grasp of the past history that gave us the OR that we have, rather than some other analytic practice. OR was thrown up by a situation where traditional management methods were proving inadequate to handle the growing complexity of organizational arrangements. Problem structuring methods (PSMs) in turn were generated out of a sense that the trajectory of OR had led it away from important areas of social decision-making. PSMs have made great strides but are still encountering barriers to acceptance. This paper will explore the factors that presently constrain PSMs, and what developments could take them into new fields.     

Tensor-Krylov methods for large nonlinear equations

In this paper, we describe tensor methods for large systems of nonlinear equations based on Krylov subspace techniques for approximately solving the linear systems that are required in each tensor iteration. We refer to a method in this class as a tensor-Krylov algorithm. We describe comparative testing for a tensor-Krylov implementation versus an analogous implementation based on a Newton-Krylov method. The test results show that tensor-Krylov methods are much more efficient and robust than Newton-Krylov methods on hard nonlinear equations problems.Part of this work was performed while the author was research associate at CERFACS (Centre Européen de Recherche et de Formation Avancée en Calcul Scientifique).Research supported in part by the Office of Scientific Computing, U.S. Department of Energy, under Contract W-31-109-Eng-38.     

Symmetry group methods for fundamental solutions

This paper uses Lie symmetry group methods to study PDEs of the form u_t=xu_xx+f(x)u_x. We show that when the drift function f is a solution of a family of Ricatti equations, then symmetry techniques can be used to find a fundamental solution.     

Quantitative problem structuring methods for multi-actor problems: an analysis of reported applications

Problem structuring methods (PSMs) are proposed as vital tools for coping with complex and unstructured problems that help decision-makers make decisions or come to a shared understanding of a problem situation. Despite their popularity, choosing a PSM for an unstructured problem situation is problematic as good categorization and evaluation of PSMs is lacking. As a first step we postulate a categorization of quantitative PSMs applied to multi-actor situations. We list the different application areas, the types of design that were used, and the type of outcomes the methods provide. To understand why and how certain PSMs are applied, we categorize applications of metagames/conflict analysis, hypergames, drama theory, Q-methodology, and transactional analysis. We find that method choice and validation of the applications are yet underdeveloped for this specific sub-field, and suggest further work on this as it will help to understand the added value of PSMs.     

On becoming expert in the use of problem structuring methods

While much has been written about the theory and practice of using problem structuring methods (PSMs) there is little formal discussion of how individuals may effectively learn about their use. In this paper it is argued that a foundation for designing and providing a suitable learning environment lies in understanding the nature of being an expert user of PSMs and the knowledge that such experts hold and deploy. An analysis of how knowledge and expertise are grounded in the work involved in using PSMs is offered. This leads to some proposals for what is required if processes to support the acquisition of expertise in the use of PSMs are to be implemented.     

Renormalization group methods

An especially intractable breed of problems in physics involves those with very many or an infinite number of degrees of freedom and in addition involve “renormalization.” Renormalization is explained as the existence of very many length or energy scales of importance in the physics of the problem. The renormalization group approach is a way of reducing the complexity of these problems to the point where numerical methods can be used to solve them. The Kondo problem (dilute magnetic alloys) is used as an illustration.     

Numerical methods for simulation of large systems

The numerical solution of large initial value problems, including those that are derived as approximations to systems of partial differential equations, may encounter difficulties using conventional numerical methods because of stiffness (large range of eigenvalues of the associated linear system). In a nonlinear system, the eigenvalues may change greatly during the solution and a system that is initially well behaved may become stiff, yielding increased computer cost or inaccuracies. This paper contains a discussion of various definitions of stiffness, and several methods for overcoming it, including a new method for identifying and partitioning a two-time-scale system into fast and slow sub-systems. Also included are some experiences using the DARE continuous system simulation language for systems as large as 200 coupled nonlinear ordinary differential equations.