The goal of this project is to understand the influence of social and cultural factors on nuclear proliferation. We identified factors that contribute to a country’s motivation to initiate a nuclear weapons program from political science literature, obtained relevant social and cultural information, and developed a system dynamics model. System dynamics is used to understand complex interactive systems with feedback. The modeling process began with the construction of a causal loop diagram, which contains the essential elements that account for nuclear proliferation and relationships between these elements. The relationships between the elements are represented by arrows that are labeled either positively or negatively to show their causal relationship. A positive sign represents a direct relationship and a minus sign represents an indirect or inverse relationship. The causal loop diagram is a mental model used to construct a stock and flow simulation model. This stock and flow model can be quantified with equations that capture the relationships amongst the elements of the system. Through system dynamics we were able to interpret the levels of variables which indicate how the system changes and gives us insight as to how each variable affects proliferation. The software used for our project was VenSim, by Ventana Systems, which enabled us to create a system dynamics model including our causal loop diagram and then place relevant variables into our stock and flow diagram. We are in the process of completing our stock and flow diagram, which will help us to gain a better understanding of the motivations for state–level nuclear proliferation. Proliferation assessment has an immense amount of factors to take into account. Through preliminary simulations of the model we demonstrated the impact of autocratic versus democratic governments on motivation to proliferate which is mediated by the differential levels of integration that results from economic trade. The model allows for expansion and lays the foundation for further investigation.


Alan Brothers

Lab site

Pacific Northwest National Laboratory (PNNL)



URL: https://digitalcommons.calpoly.edu/star/13


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