Using the Data Envelopment Analysis (DEA) technique and the Malmquist Productivity Index, this article studies emission efficiency across Taiwan's manufacturing sectors. Understanding emission efficiency within industrial sectors is critical for directing effective policymaking and fostering sustainable development in light of growing concerns about environmental sustainability and the need to reduce greenhouse gas emissions. The study makes use of a dataset from 20 manufacturing subsectors in Taiwan during the period 1998-2020. DEA is used to assess the emission efficiency of these decision-making units and compare their performance to peers. Furthermore, the Malmquist Productivity Index is used to examine efficiency changes over time, offering insights into the progress and technical breakthroughs achieved in emission reduction initiatives. The research contributes to the limited body of literature focused on emission efficiency analysis in Taiwan. These findings reveal considerable differences in emission efficiency across Taiwan's various manufacturing sectors. Some industries have superior emission efficiency, while others have space for development. Finally, this study adds to a better knowledge of emission efficiency in Taiwan's manufacturing sectors and lays the groundwork for evidence-based policies.

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