Vensim

Last updated
Vensim
Developer(s) Ventana Systems, Inc.
Initial release1990(34 years ago) (1990)
Stable release
Version 9.3.2 / July 2022(2 years ago) (2022-07)
Written inC
Operating system Windows and OS X applications, Linux and iOS libraries
Type Simulation software
License Proprietary
Website vensim.com

Vensim is a simulation software developed by Ventana Systems. It primarily supports continuous simulation (system dynamics), with some discrete event and agent-based modelling capabilities. It is available commercially and as a free "Personal Learning Edition".

Contents

Modeling environment

Vensim provides a graphical modeling interface with stock and flow and causal loop diagrams, on top of a text-based system of equations in a declarative programming language. It includes a patented method for interactive tracing of behavior through causal links in model structure (the patent expired in 2012), [1] [2] [3] as well as a language extension for automating quality control experiments on models called Reality Check. [4]

The modeling language supports arrays (subscripts) and permits mapping among dimensions and aggregation. Built-in allocation functions satisfy constraints that are sometimes not met by conventional approaches like logit. [5] It supports discrete delays, queues and a variety of stochastic processes.

There are multiple paths for cross sectional and time-series data import and export, including text files, spreadsheets and ODBC. Models may be calibrated against data using optimization, Kalman Filtering [6] or Markov chain Monte Carlo methods. Sensitivity analysis options provide a variety of ways to test and sample models, including Monte Carlo simulation with Latin Hypercube sampling.

Vensim model files can be packaged and published in a customizable read-only format that can be executed by a freely available Model Reader. This allows sharing of interactive models with users who do not own the program and/or who the model author does not wish to have access to the model's code base. [7]

Applications

Vensim is general-purpose software, used in a wide variety of problem domains. Common or high-profile applications include:

See also

Related Research Articles

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References

  1. "Vensim Causal Tracing™". Vensim - Ventana Systems.
  2. "Simulation system employing causal tracing. US Patent Application EP19910909851, Feb. 26 1991".
  3. "Applying successive data group operations to an active data group. Patent # 5,428,740". Justitia.com.
  4. Peterson, David W.; Eberlein, Robert L. (1994). "Reality check: A bridge between systems thinking and system dynamics". System Dynamics Review. 10 (2–3): 159–174. doi: 10.1002/sdr.4260100205 .
  5. Vensim Allocation by Priority
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  17. Sterman, John D.; Fiddaman, Thomas; Franck, Travis; Jones, Andrew; McCauley, Stephanie; Rice, Philip; Sawin, Elizabeth; Siegel, Lori (2013). "Management flight simulators to support climate negotiations". Environmental Modelling & Software. 44: 122–135. doi:10.1016/j.envsoft.2012.06.004.
  18. Weller, Florian; Sherley, Richard B.; Waller, Lauren J.; Ludynia, Katrin; Geldenhuys, Deon; Shannon, Lynne J.; Jarre, Astrid (2016). "System dynamics modelling of the Endangered African penguin populations on Dyer and Robben islands, South Africa". Ecological Modelling. 327: 44–56. doi:10.1016/j.ecolmodel.2016.01.011.
  1. Martinez-Moyano, I. J. (2012). "Documentation for model transparency". System Dynamics Review. 28 (2): 199–208. doi: 10.1002/sdr.1471 .