Abstract
The main objective of this article is to demonstrate how fuzzy-set Qualitative Comparative Analysis (fsQCA) can be successfully applied to assess the conditions of municipal solid waste (MSW) treatment efficiency by comparing the results with those obtained from tobit regression modeling (TRM). TRM identifies two factors significantly determining MSW treatment efficiency: R&D expenditure and educational attainment (levels 5–8). The variables directly related to the MSW treatment process – private investment in circular economy sectors and circular material use (CMU) – turn out to be insignificant. FsQCA provides more detailed insights and shows that a high level of R&D expenditure is necessary but not sufficient to achieve a high level of MSW treatment efficiency. This means that, in addition to increasing R&D expenditure, countries need to do more to achieve a high level of MSW treatment. Moreover, fsQCA shows that both high and low levels of private investment can be a source of high MSW treatment efficiency, which explains the insignificance of private investment in the TRM. Based on the results of Qualitative Comparative Analysis, several recommendations are made in the article for countries with low MSW treatment efficiency. The research confirms that fsQCA provides a more detailed analysis than regression modeling alone.