## 3 System Dynamics and Agent-Based Modeling and Simulation Techniques
### Modeling and Simulation Tools  
Several modeling and simulation tools are available on the market. Some are for free use; others are proprietary toolkits for commercial use. Examples of such tools can be found in [41; 42; 43].  
Within recent decades, several software tools have been developed and applied by SD and AB modelers. SD tools have reached a greater stage of maturity than those for AB-based modeling, but still offer many areas for growth. A summary of some simulation tools that feature either SD and AB paradigms, as well as hybrid SD-AB modeling, is given in Table 2.  
The choice of the appropriate tool to satisfy a certain problem is not easy, due to the inherent complexity of systems. In this work, the selection criteria was first based on tools that provide a hybrid SD-AB approach, second on the license character, with a preference for free licenses, and finally on the  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Tool** & **SD** & **AB** & **Characteristics** \\ \hline Versim (www.vensim.com) & X & & Free version \\ \hline Repast Simphony & & \multicolumn{2}{c}{Dedicated AB prototyping environment} \\ (Repast S) & & X & Large-scale (scalable) agent development environment \\ ([[https://repast.github.io/](https://repast.github.io/)]([https://repast.github.io/](https://repast.github.io/))) & & & Free version \\ \hline NetLogo & & \multicolumn{2}{c}{Dedicated AB prototyping environment} \\ ([[https://ccl.northwestern.edu/netlogo/](https://ccl.northwestern.edu/netlogo/)]([https://ccl.northwestern.edu/netlogo/](https://ccl.northwestern.edu/netlogo/))) & X & Modified version of the Logo programming language \\  & & & Free \\ \hline Swarm & & \multicolumn{2}{c}{Large-scale (scalable) agent development environment.} \\ ([[http://www.swarm.org/](http://www.swarm.org/)]([http://www.swarm.org/](http://www.swarm.org/))) & & X & Java interface \\  & & & Free \\ \hline AnyLogic & & \multicolumn{2}{c}{Multi-method tool} \\ (www.anylogic.com) & X & X & Integration and interaction of the two methods \\  & & \multicolumn{2}{c}{Large-scale (scalable) agent development environment} \\  & & & \multicolumn{2}{c}{Large-scale (scalable) agent development environment} \\  & & & \multicolumn{2}{c}{Java} \\  & & & Proprietary toolkit (free version for students) \\ \hline Insight Maker & & \multicolumn{2}{c}{X} & \multicolumn{2}{c}{Online software} \\ (www.insightmaker.com) & & & Free \\ \hline MASON & & \multicolumn{2}{c}{Large-scale (scalable) agent development environment} \\ ([[https://cs.gmu.edu/](https://cs.gmu.edu/)]([https://cs.gmu.edu/](https://cs.gmu.edu/))\(\sim\)|jeclab/projects/mason/) & & & Java \\ \hline Stella/fThink & & \multicolumn{2}{c}{Multi-method tool (depending on the products)} \\ ([[https://www.iseesystems.com/store/products/ithink.aspx](https://www.iseesystems.com/store/products/ithink.aspx)]([https://www.iseesystems.com/store/products/ithink.aspx](https://www.iseesystems.com/store/products/ithink.aspx))) & & & Proprietary toolkit \\ \hline PowerSim & & \multicolumn{2}{c}{Build models with the System Dynamics approach} \\  & & \multicolumn{2}{c}{Run what-if scenarios and do policy design} \\ (www.powersim.com) & X & Quickly assemble a flexible user interface \\  & & \multicolumn{2}{c}{Connect to MS Excel or different Databases} \\  & & & Free \\ \hline NOVA & & \multicolumn{2}{c}{Multi-method tool} \\ (www.novamodeler.com) & X & X & Java-based modeling platform \\  & & & Free version \\ \hline \hline \end{tabular}
\end{table}
Table 2: Some of the available modeling and simulation tools for system dynamics (SD) and agent-based (AB)modeling tool experience of the authors. In this line, the adopted tool is the AnyLogic tool that will be further described in Section 5.