The Dynamics of the Field of System Dynamics

by

Deborah L. Andersen

Rockefeller College

SUNY Albany

Albany, NY 12222, USA

dla@cnsvax.albany.edu

 

Michael J. Radzicki

Department of Social Science & Policy Studies

Worcester Polytechnic Institute

Worcester, MA 01609, USA

mjradz@wpi.edu

 

Roberta L. Spencer

Milne 300

Rockefeller College

SUNY Albany

Albany, NY 12222, USA

System.Dynamics@albany.edu

W. Scott Trees

Department of Economics

Siena College

Route 9

Loudonville, NY 12211, USA

trees@siena.edu

 

Shoemakers are always the worst shod.[1]

 

Future of the Field Project

Although the field of system dynamics has had many noteworthy successes during the preceding forty-one years,[2] some system dynamicists[3] would argue that it is not as “well-known, widely used, extensively taught, respected and influential as it ‘should be’ based on the breadth and power of its principles and the need of industry and society for dynamic analysis”[4] of the type that system dynamics can offer. The purpose of this paper is to provide an overview of an on-going project, recently initiated by the authors, to systematically investigate the possible futures for, and reasons for the below-potential growth of, the field of system dynamics.

As can be seen in Figure 1, the “Future of the Field” project consists of four primary, interactive, activities:

1.   Organize Existing Data. This activity includes archiving the Field's historical documents, making data available on the System Dynamics Society's web site, and assembling reference mode data to assist in the creation of system dynamics models for new initiatives and policy analysis.

2.   System Dynamics Modeling. This activity involves the creation of a series of system dynamics models, from new and existing data and knowledge of the Field, that address questions related to the future of the Field. These models will be available via the Society's web site.

3.   New Policies and Initiatives. This activity involves the implementation of new policies and initiatives devised via system dynamics modeling and the collection and analysis of data from the Field.

4.   Collect New Data. This activity involves the collection of new data for the purpose of validating/altering the relationships put forth in the system dynamics models of the Field. It will also enable the responses of the Field to new initiatives and policies to be measured and will facilitate the creation of an on-going process of program evaluation (see Ganter et al. 1995).

Future of the Field Modeling

As shown in Figure 2, the first model created for the project examines the interactions between the structure of the supply side of the Field, the demand side of the Field, the System Dynamics Society, and the Society's annual conference, and the dynamic behavior of the Field.

Figure 3 shows four time series plots from two simulations of the Future of the Field model. The first simulation run (run 1 in all of the plots) mimics the actual behavior of the Field from 1956 to 1997 and serves as the model’s base case. In this run, the number of veteran system dynamicists rises to approximately 550 by 1997, the Field exhibits an annual growth rate of approximately 15% (except during its initial years and the mid-1970s through the early-1980s), the average quality of system dynamics projects remains very high throughout the 1960s and 1970s, but begins to decline during the 1980s and 1990s, and the number of published system dynamics studies reaches a level of approximately 5000.

The second simulation run (run 2 in all of the plots) shows what would have happened during the last forty-one years of the Field’s existence if the normal fraction of veteran system dynamicists who teach system dynamics to rookies were 14% (instead of 12% as in the base run). Clearly, the additional fraction of veterans who are able to train new modelers causes a much larger growth in the field. Of note, however, is that the average quality of system dynamics projects still declines due to the flood of rookie modelers during the 1990s.

Conclusions

If the Field of system dynamics has been growing below its potential since its inception, the tools of system dynamics should be used to determine how the situation can be corrected. It is the authors’ hope that the research underlying this paper will be the first step in an on-going research project aimed at continuously examining the future of the field of system dynamics.

Bibliography

Fey, Willard. 1981. “The Dynamics of System Dynamics.” Proceedings of the 1981 International Conference on Cybernetics and Society. New York: Institute of Electrical and Electronic Engineers.

Ganter, Susan L., James K. Doyle, and Michael J. Radzicki. 1995. “Assessing System Dynamics Curricula: Past, Present, and Future. ”pp. 484-493. In: Toshiro Shimada and Khalid Saeed, eds. Proceedings of the 1995 International Conference of the System Dynamics Society. Gakushuin University. Tokyo, Japan. July 30-August 4.

Greenberger, Martin, Matthew A. Crenson and Brian L. Crissey. 1976. Models in the Policy Process: Public Decision Making in the Computer Era. New York: Russell Sage Foundation. Distributed by Basic Books.

Maloney, Stephen. 1993. “Notes and Insights on Essential Tension.” System Dynamics Review 9(3): 301-305.

Richardson, George P. 1996. “Problems for the Future of System Dynamics.” System Dynamics Review 12(2): 141-157.

Scholl, Greg J. 1995. “Benchmarking the System Dynamics Community: Research Results.” System Dynamics Review 11(2): 139-155.

Scholl, Greg J. 1992. “Benchmarking the System Dynamics Community.” System Dynamics Review 8(3): 263-266.

Scholl, Greg J. 1991. The Dynamics of System Dynamics: Past and Future. Unpublished Undergraduate Thesis. Harvard College. Harvard University Archives. Cambridge, MA 02138.

Sterman, John D. 1992. “Opening Speech: 1992 International System Dynamics Conference.” System Dynamics Group. Massachusetts Institute of Technology.

Figure 1: Overview of the Future of the Field Project

Figure 2: Overview of the Future of the Field Model

 

Figure 3: Two Simulation Runs from the Future of the Field Model



[1] Old French proverb. Fey (1981, p. 3).

[2] See Greenberger et al. (1976) and Sterman (1992) for some examples.

[3] For example Fey (1981), Scholl (1991, 1992, 1995), and Maloney (1993).

[4] Fey (1981, p. 1).