"background": "Power-distribution systems in many African nations face significant efficiency challenges, with technical losses and yield deficits constraining economic development. A rigorous methodological framework for evaluating the impact of equipment upgrades on system yield is required to inform infrastructure investment. ", "purpose and objectives": "This study aims to develop and apply a quasi-experimental econometric model to quantify the causal effect of modernising power-distribution equipment on technical yield within a national grid. The objective is to provide an evidence-based evaluation methodology for engineering interventions. ", "methodology": "A difference-in-differences (DiD) model was employed, analysing panel data from treated and control regions. The core specification is Y{it = \0 + \1 + \2 + \ (\) + \₈ₓ, where \ is the average treatment effect. Inference is based on cluster-robust standard errors at the regional level. ", "findings": "The modernisation programme significantly improved aggregate technical yield by an estimated 7. 3 percentage points (95% CI: 5. 1, 9. 5). The DiD estimator \\ was statistically significant at the 1% level, indicating a strong positive causal effect of the equipment interventions. ", "conclusion": "The application of a difference-in-differences model provides a robust methodological framework for evaluating engineering upgrades in power distribution, confirming that targeted equipment modernisation is a potent driver of yield improvement. ", "recommendations": "Utilities should adopt quasi-experimental evaluation designs for major capital projects. Policy should prioritise investment in regions with the highest pre-intervention loss profiles, as modelled by the treatment effect heterogeneity analysis. ", "key words": "difference-in-differences, power distribution, technical yield, quasi-experimental, infrastructure evaluation, grid modernisation", "contribution statement":
Mwangi et al. (Wed,) studied this question.