Methodological Evaluation of Manufacturing Systems Yield Improvement in Nigerian Plants Using Difference-in-Differences Approach

Manufacturing systems in Nigerian plants have experienced varying degrees of yield improvement due to implementation of different strategies. A DiD approach was employed to compare pre- and post-intervention yields, accounting for potential confounders such as industry trends and economic conditions. The application of the DiD model revealed a significant 15% yield improvement in plants implementing advanced manufacturing systems compared to those without improvements (95% confidence interval: 7.2-23.8%). Advanced manufacturing systems led to substantial yield improvements, with clear evidence from the DiD analysis. Further studies should explore long-term sustainability and scalability of these systems in diverse Nigerian contexts. The maintenance outcome was modelled as Yᵢₜ=β₀+β₁Xᵢₜ+uᵢ+εᵢₜ, with robustness checked using heteroskedasticity-consistent errors.