# A Regret-Enhanced DEA Approach to Mapping Renewable Energy Efficiency in Asia's Growth Economies
###### Abstract
Collaborative efforts among ASEAN member states, along with support from international partners, are crucial in surmounting these hurdles and accelerating the transition [17]. However, challenges remain in terms of policy frameworks, grid integration, and technological advancements [18]. While the potential for renewable energy is vast, fostering a conducive investment environment and ensuring a seamless transition from conventional sources demand concerted efforts from governments, international organizations, and private sector stakeholders [8; 19]. The role of investment efficiency assessment is paramount in ensuring the optimal allocation of resources and maximizing the impact of renewable energy initiatives [20]. As global focus shifts toward sustainable energy sources, understanding the effectiveness of renewable energy investments becomes essential for informed decision making. Investigations into renewable energy investments have emerged as a pivotal area of research, fueled by the global imperative for sustainable and cleaner energy solutions. Scholars have diligently examined various dimensions of this topic, shedding light on its economic, environmental, and societal implications [4; 5; 8; 21; 22; 23; 24; 25; 26; 27; 28]. In response, Data Envelopment Analysis (DEA) has been widely applied to assess energy efficiency and sustainability across different national and regional contexts, such as in Algeria, Turkey, Korea, East Asia, the Czech Republic, and China [29; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44]. More recent international studies have expanded this approach by integrating behavioral insights into the DEA framework [45; 46; 47]. For instance, behavioral DEA models incorporating loss aversion or regret preferences have been applied to environmental regulation, carbon trading, and green investment evaluations [48; 49; 50; 51]. These models acknowledge that decision makers often deviate from purely rational behavior, instead reacting based on anticipated emotions such as regret or rejoic. Regret theory, in particular, has been shown to provide a powerful behavioral dimension to performance evaluation [52; 53], and its integration with DEA introduces a more holistic approach to decision making under uncertainty. Although these advances are notable, most of these applications focus on developed economies or firm-level analyses. The present study contributes to this evolving literature by applying a rejoice-regret utility cross-efficiency DEA (RRUCE-DEA) model to the context of renewable energy  
Figure 2: Global renewable energy investment [16]. investment efficiency in South and Southeast Asia--regions that have received limited attention in prior behavioral DEA research. Unlike previous studies that evaluate efficiency at a single-point frontier or focus on organizational units, this study incorporates cross-evaluation across multiple countries and explicitly embeds rejoice-regret behavioral responses in both input and output transformation. To the best of our knowledge, this is the first application of the RRUCE-DEA model to a multi-country assessment of RE investment efficiency in emerging Asian economies, offering both empirical benchmarks and methodological innovation.