Modelling of ecological and/or economic systems is a complex, yet essential, task. In recent years, improved modelling software and computer hardware have made at least the technical part of the task much easier. It is now possible to devote more of the modelling effort to using the model to understand the system rather than simply in coding and debugging the model. This increased ease of construction also helps prevent the modeler from ‘falling in love’ with the model, and allows changes in model structure to be more easily effected and their implications analyzed. The papers in this special issue are the product of a graduate level modelling course/ workshop held at the Department of Systems Ecology, Stockholm University, between September and December 1995. The course/workshop brought together a diverse group of researchers, each with a particular research question that could benefit from a dynamic modelling approach. Many of the participants had little or no previous modelling experience. Therefore, we needed a modelling package that would allow participants to begin modelling in a short time. There are various graphical programming languages available that are specifically designed to facilitate modelling of nonlinear, dynamic systems. Among the most versatile of these languages is the graphical programming language STELLA II (Costanza, 1987; Hannon and Ruth, 1994; Richmond and Peterson, 1994) which we employed in the course. STELLA II runs in both the Macintosh and MS-Windows environments and models created in either environment can run in the other. The language is described in a little more detail below. The course was organised as an interactive workshop where there was little distinction between teacher and student. Several faculty and students participated. The first several sessions were an introduction to dynamic systems modelling and STELLA with several examples. Participants then began to ‘learn by doing’ by building their own models, either individually or in a team. Most of the remaining sessions * Corresponding author. E-mail: costza@cbl.umces.edu 1 Tel.: +46 8 164258; fax: +46 8 158417; e-mail: danield@system.ecology.su.se 2 E-mail: ulrik@system.ecology.su.se
[1]
C. S. Holling.
The functional response of invertebrate predators to prey density
,
1966
.
[2]
Robert Costanza,et al.
Simulation modeling on the Macintosh using STELLA
,
1987
.
[3]
Thomas Maxwell,et al.
Distributed modular spatial ecosystem modeling
,
1995,
Int. J. Comput. Simul..
[4]
C. S. Holling.
The Analysis of Complex Population Processes
,
1964,
The Canadian Entomologist.
[5]
K. Mäler,et al.
Modeling Complex Ecological Economic Systems: Toward an Evolutionary, Dynamic Understanding of People and Nature
,
1993
.
[6]
R. Levins.
The strategy of model building in population biology
,
1966
.