Michael Pidd

A conceptual framework for understanding business processes and business process modelling

It is increasingly common to describe organizations as sets of business processes that can be analysed and improved by approaches such as business process modelling. Successful business process modelling relies on an adequate view of the nature of business processes, but there is a surprising divergence of opinion about the nature of these processes. This paper proposes a conceptual framework to organize different views of business processes under four headings. It also aims at providing an integrated discussion of the different streams of thought, their strengths and limitations, within business process modelling. It argues that the multifaceted nature of business processes calls for pluralistic and multidisciplinary modelling approaches.

Discrete event simulation for performance modelling in health care: a review of the literature

Discrete Event Simulation (DES) has been widely used in modelling health-care systems for many years and a simple citation analysis shows that the number of papers published has increased markedly since 2004. Over the last 30 years several significant reviews of DES papers have been published and we build on these to focus on the most recent era, with an interest in performance modelling within hospitals. As there are few papers that propose or illustrate general approaches, we classify papers according to the areas of application evident in the literature, discussing the apparent lack of genericity. There is considerable diversity in the objectives of reported studies and in the consequent level of detail: We discuss why specificity dominates and why more generic approaches are rare.

Discrete-event simulation is dead, long live agent-based simulation!

There has been much discussion about why agent-based simulation (ABS) is not as widely used as discrete-event simulation in Operational Research (OR) as it is in neighbouring disciplines such as Computer Science, the Social Sciences or Economics. To consider this issue, a plenary panel was organised at the UK Operational Research Societys Simulation Workshop 2010 (SW10). This paper captures the discussion that took place and addresses the key questions and opportunities regarding ABS that will face the OR community in the future.

A simulation model for emergency evacuation

Abstract This paper describes the development of a prototype spatial decision support system for use by emergency planners in developing contingency plans for evacuations from disaster areas. It links together a geographical information system (ARC/INFO) with a specially written object-oriented micro-simulator via a windowing computer operating system. The details of the system are described, its limitations are discussed and potential enhancements are identified.

Just Modeling Through: a Rough Guide to Modeling

Skill in modeling is one of the keys to success in OR/MS practice. This has been recognized for many years, but we often give it only lip service. Models are used in many ways in OR/MS practice. A few simple principles of modeling may be useful. The six principles discussed here cover simplicity versus complexity; model development as a gradual, almost piecemeal process; dividing larger models into smaller components; using analogies; proper uses of data; and finally the way in which the modeling process can seem chaotic. Others may wish to comment on these principles and add their own.

Perversity in public service performance measurement

Purpose – To discuss some of the reasons why performance measurement systems in public services can lead to dysfunctional consequences even when people operate with the best of intentions.Design/methodology/approach – The paper draws together literature from the UK public sector, from writers in performance measurement and from cultural insights in anthropology to understand why some of these perverse effects occur.Findings – Though many reasons are cited for public service performance measurement regimes, it is clear that control aspects dominate the others. This, when allied to an unthinking use of cybernetic metaphors, is what can lead to dysfunctionality.Originality/value – The paper should appeal to those who wish to improve the performance of performance measurement systems in public services and to those who wish to understand why things can go wrong.

Understanding accident and emergency department performance using simulation

As part of a larger project examining the effect of performance targets on UK hospitals, we present a simulation of an Accident and Emergency (A&E) Department. Performance targets are an important part of the National Health Service (NHS) performance assessment regime in the UK. Pressures on A&Es force the medical staff to take actions meeting these targets with limited resources. We used simulation modelling to help understand the factors affecting this performance. We utilized real data from patient admission system of an A&E and presented some data analysis. Our particular focuses are the multitasking behaviour and experience level of medical staff, both of which affect A&E performance. This performance affects, in turn, the overall performance of the hospital of which it is part

Simulation model reuse: definitions, benefits and obstacles

Abstract The term ‘simulation model reuse’ can be taken to mean various things from the reuse of small portions of code, through component reuse, to the reuse of complete models. On a more abstract level, component design, model design and modelling knowledge are prime candidates for reuse. The reuse of simulation models is especially appealing, based on the intuitive argument that it should reduce the time and cost for model development. In a discussion with four simulation modelling experts, however, a number of issues were raised that mean these benefits may not be obtainable. These issues include the motivation to develop reusable models, the validity and credibility of models to be reused, and the cost and time for familiarisation. An alternative simulation methodology was proposed, that may lend itself better to model reuse.

Wisdom, decision support and paradigms of decision making

Many decision support tools have been developed over the last 20 years and, in general, they support what Simon termed substantive rationality. However, such tools are rarely suited to helping people tackle wicked problems, for which a form of procedural rationality is better suited. Procedurally rational approaches have appeared in both management science and computer science, examples being the soft OR approach of cognitive mapping and the design rationale based on IBIS. These approaches are reviewed and the development of Wisdom, a procedurally rational decision support process and accompanying tool, is discussed and evaluated. � 2004 Elsevier B.V. All rights reserved.

Use of business process simulation: A survey of practitioners

In order to understand the requirements of people engaged in business process simulation (BPS), a survey was conducted among potential business process simulation users. The survey had a 37% response rate and revealed a low usage of simulation in the design, modification and improvement of business processes. It confirms that BPS projects are typically short, relatively non-technical, and rely on good project management for their success. Most BPS users employ general-purpose simulation software rather than purpose-designed business process simulators. There is no evidence of a skills gap, rather a feeling that there is no net gain from employing simulation methods when simpler methods will suffice. These findings are discussed and conclusions drawn.