Interactive models have been increasingly used in social science research to assess conditional theoretical expectations and hypotheses empirically. However, the direct, indirect, and marginal effects of the constitutive terms in interactive linear and non-linear models are often erroneously calculated and interpreted. This study examines the contemporary political methodology literature pointing to various sources of such errors and presenting alternative methods to calculate marginal effects and diagnostic tools. The proposed methods and statistical tools are then examined with the help of several applied and hypothetical examples, and several essential takeaways are summarized in the concluding section. Consequently, this study aims to help Turkish scholars avoid similar errors in positing conditional expectations, testing those using quantitative methods, and interpreting their findings.