Methodological Evaluation of Manufacturing Plants Systems in Nigeria Using Time-Series Forecasting Models for Cost-Efficiency Measurement

This study addresses a current research gap in Engineering concerning Methodological evaluation of manufacturing plants systems in Nigeria: time-series forecasting model for measuring cost-effectiveness in Nigeria. The objective is to formulate a rigorous model, state verifiable assumptions, and derive results with direct analytical or practical implications. A structured analytical approach was used, integrating formal modelling with domain evidence. The results establish bounded error under perturbation, a convergent estimation process under stated assumptions, and a stable link between the proposed metric and observed outcomes. The findings provide a reproducible analytical basis for subsequent theoretical and applied extensions. Stakeholders should prioritise inclusive, locally grounded strategies and improve data transparency. Methodological evaluation of manufacturing plants systems in Nigeria: time-series forecasting model for measuring cost-effectiveness, Nigeria, Africa, Engineering, comparative study This work contributes a formal specification, transparent assumptions, and mathematically interpretable claims. The maintenance outcome was modelled as Y₈ₓ=₀+₁X₈ₓ+uᵢ+₈ₓ, with robustness checked using heteroskedasticity-consistent errors.