Elasticities for circular-economy substitution: systematic review and meta-analysis (new vs non-new products; virgin vs recycled materials)

This preregistered project conducts two coordinated systematic reviews with meta-analytic synthesis of empirical elasticities that govern substitution between circular and linear options, with the objective of producing parameter ranges and (where feasible) pooled estimates that can be used in theoretical and numerical equilibrium models of the circular economy. Review 1 (demand side) covers substitution for durables between purchasing new products and non-new alternatives, including (i) repair/maintenance services that extend product lifetime and (ii) acquisition of remanufactured/refurbished/reused/second-hand products. Review 2 (production side) covers substitution or transformation between virgin/primary materials and recycled/secondary materials (including scrap/recyclate inputs). The two strands are synthesised separately because they differ in mechanisms, study designs, and effect definitions, but will be reported together as a coherent evidence base for circular-economy modelling. The review will follow PRISMA 2020 for reporting. Screening and data extraction will be AI-assisted using prismAId, with prespecified prompts, human oversight, and reconciliation procedures documented in the protocol. Extracted estimates will be harmonised onto comparable effect definitions where possible (e.g., mapping reported own-/cross-price elasticities, demand-system parameters, or cost-share equation parameters to implied elasticities of substitution consistent with CES/Armington-style nests). The expected outcomes are (i) a transparent inventory of relevant empirical estimates, (ii) harmonised datasets of elasticity estimates, and (iii) synthesised ranges/distributions (and pooled estimates for sufficiently comparable subsets) stratified by product/material category, sector, geography (including EU27 and Norway where relevant), time horizon (short vs long run), and estimation approach.