Regarding case range, Gary King, Robert Keohane, and Sidney Verba alert against "selecting around the dependent variable". They argue one example is that scientists simply cannot make legitimate causal inferences about war outbreaks by only checking out occasions where war did occur (the researcher also needs to look at cases https://hiresomeonetowritecasestu42950.blogrelation.com/38277655/the-ultimate-guide-to-case-solution