23  Supporting simulation literature

Agent-based modelling and system dynamics are supporting modelling traditions, not methods in the book’s comparative small-n corpus. They are retained because they can strengthen a causal analysis when a model is built around an evaluand, its mechanisms, and plausible alternatives. The large number of publications naming either approach cannot be read as evidence that they are widely used in evaluation. Across the two review stages, 73 of 80 sampled records used the intended model term and 24 were coded as applications. The review was stratified to test the search terms, so these figures do not estimate the share of the wider literature that is evaluative.

Figure 23.1 describes the supporting literature only. It counts indexed works that name the relevant model in a title or abstract. It does not count evaluation applications, development evaluations, or uses alongside the core methods. Those claims require record-level screening under the rules set out in the Methods appendix.

Figure 23.1: Indexed literature naming supporting simulation models. Counts are surface mentions, not evaluation applications.

The distinction matters in practice. A model of disease transmission, supply chains, or organisational behaviour may offer relevant background, but it is an evaluation application only when it is used to assess an identifiable intervention or policy choice. Eight sampled applications were coded as development-related. This appendix remains separate from the comparative core-method figures because model mentions do not identify evaluation use.