The Impact of Open Competition Method Compared to Restricted/Selective Tendering Methods: Comparative Analysis in Public Procurement in Nigeria

Background: Public procurement methods significantly influence transparency and cost efficiency. Objective: To compare open and restricted procurement methods in different contexts. Methods: An empirical study was conducted through surveys, interviews, and machine learning clustering analysis. Results: Open bidding was rated high for fairness (mean = 4.42) and value for money (mean = 4.27), and restricted methods favored urgency and complexity. Conclusion: Context-sensitive procurement frameworks combining both methods are ideal. A decision support model was proposed for policy implementation. Plain Language Summary: This study compares two methods of public procurement— open competitive bidding and restricted tendering—to determine which works best in different situations. Using survey and statistical data from Nigeria, West Africa, and the UK, this study shows that open bidding is better for fairness and transparency, while restricted methods are useful for urgent or complex projects. A new decision model is proposed to help governments choose the right method based on context.