en Mathematical Modeling and Applications of OR Mathematical Modeling and Applications of OR پژوهشی Original <span style="font-size:11pt"><span style="line-height:normal"><span style="text-autospace:none"><span new="" roman="" style="font-family:" times=""><i><span style="font-size:10.0pt"><span style="letter-spacing:-.25pt">Supply chains often have different technologies. Additionally, organizations with multiple stages can evaluate their operational efficiency by analyzing scale elasticity, which helps determine if they are functioning optimally or if there is room for improvement. This evaluation allows for the identification of potential inefficiencies and opportunities for enhancement. Consequently, this research introduces a two-stage DEA-based approach with undesirable outputs to examine the scale elasticity of supply chains within meta and group frontiers. The measurement of group and meta performance of general systems and stages is conducted for this purpose. Moreover, the study addresses the scale elasticity of supply chains with undesirable outputs by considering the heterogeneity of technologies. To achieve this, the study focuses on the right and left scale elasticity of efficient general systems and each stage. A real-world application from the soft drink industry is provided to illustrate the proposed model. The results show the applicability of the introduced methodology.</span></span></i></span></span></span></span><br> &nbsp; scale elasticity, supply chains, DEA, meta-frontier, undesirable outputs 136 148 http://iors.ir/journal/browse.php?a_code=A-10-304-6&slc_lang=en&sid=1 Roghayeh Azizi Usefvand rayhaneh_azizi@yahoo.com 00031947532846002821 00031947532846002821 No Department of Industrial Engineering, Lahijan Branch, Islamic Azad University, Lahijan, Iran Sohrab Kordrostami sohrabkordrostami@gmail.com 00031947532846002822 00031947532846002822 Yes Department of Mathematics, Lahijan Branch, Islamic Azad University, Lahijan, Iran Alireza Amirteimoori aamirteimoori@gmail.com 00031947532846002823 00031947532846002823 No Faculty of Engineering & Natural Sciences, Istinye University, Istanbul, Turkey Maryam Daneshmand-Mehr m.daneshmand2010@gmail.com 00031947532846002824 00031947532846002824 No Department of Industrial Engineering, Lahijan Branch, Islamic Azad University, Lahijan, Iran