When Dyadic Analysis Is the Right Choice in Conflict Research

What Diehl and Wright Argue

Paul F. Diehl and Thorin M. Wright offer a clear, conditional defense of the dyadic approach to studying interactions between two actors in international studies. They acknowledge that choosing units of analysis always simplifies reality, but argue that current critiques do not eliminate the dyad as a useful and sometimes preferable simplification for many questions in conflict research.

Why Dyads Matter

The authors situate the dyadic approach as a theoretically driven choice: when the research question and causal theory focus on pairwise interactions (for example, conflict, alliance choices, or reciprocity between two states), modeling the dyad — a two-actor interaction — can provide the most coherent and directly relevant unit of analysis.

Three Core Issues Evaluated

• Level of analysis: Diehl and Wright stress that selecting dyads depends on whether the causal process of interest operates primarily between pairs rather than at the state, system, or network level.
• Independence of cases: they engage the common critique that dyadic observations may violate independence assumptions and discuss how the validity of dyadic inference hinges on whether dependence across dyads matters for the particular question and model.
• Cumulative benefits of past research: the authors highlight that a substantial body of dyadic work has produced generative insights and methods that remain valuable when applied with appropriate theoretical justification.

What This Means for Researchers

Diehl and Wright do not claim dyads are always optimal. Instead, they recommend treating the dyadic choice as a defensible, theory-led simplification: scholars should match unit of analysis to causal theory, be explicit about assumptions regarding case independence, and weigh the explanatory gains from prior dyadic findings against potential limitations.

Implications for the Field

This conditional defense reframes debates about units of analysis away from categorical rejection or endorsement of dyads and toward a pragmatic, question-driven evaluation. It encourages scholars in international relations and conflict studies to justify their unit choices in light of theory, potential dependence, and the analytic trade-offs involved.