This is a simulation tool for the paper “The Statistical Physics of Psychological Networks: Zero matters” of van der Maas et al. (2025).
It requires installation of Netlogo (https://www.netlogo.org/), an open-source, multi-platform, multi-agent simulation environment that allows users to model and explore complex systems by defining simple rules for large numbers of interacting agents. The download
It allows readers new to this type of modeling to visually verify the properties of several spin models. The program incorporates the Ising, Blume Capel (BC), Ubics, Blume-Emery-Griffiths (BEG) model, different network types (Lattice, Erdős–Rényi, prefential-attachment), and allows one to vary network size, connectivity and connection strength. In addition, spin values can take on any number between -1 and 1 (the general-spin case). Also, mixtures of node types (some being only negative or positive) can be investigated. The main model parameters a,T (1⁄β),τ, and ρ can be varied while nodes are continuously updated. This way the user can move over the phase diagram (figure 3 in the paper). A more systemtic approach is to construct bifurcation plots. One can select one of the variables, set its mimimum and maximum, and the speed of change in this variable. The bifurcation plot shows the resulting bifurcation. Specific scenarios are readily accessible and will be referenced throughout the paper.