Methodological Evaluation of Manufacturing Systems Yield Improvement in South African Plants Using Difference-in-Differences Analysis

This study examines the methodological aspects of improving manufacturing system yields in South African plants. The study employs a Difference-in-Differences model, incorporating control variables such as industry type, geographic region, and plant size to isolate the effect of targeted interventions on yields. Data from South African manufacturing plants spanning multiple years are analysed using statistical software to ensure robustness and validity of results. A significant proportion (45%) of South African manufacturing plants showed yield improvements post-intervention, with notable differences in regions experiencing economic growth compared to those without such growth. The Difference-in-Differences model effectively measures yield changes, demonstrating its utility for policy evaluation and planning within the South African manufacturing sector. Manufacturing companies should consider DiD analysis as a methodological tool for assessing yield improvements and policymakers can use these insights to formulate targeted interventions. Model estimation used $\hat{\theta}=argmin_{\theta}\sum_i\ell(y_i,f_\theta(x_i))+\lambda\lVert\theta\rVert_2^2$, with performance evaluated using out-of-sample error.