Performance evaluation of problematic samples: a robust nonparametric approach for wastewater treatment plants

Abstract

This paper explores robust unconditional and conditional nonparametric approaches to support performance evaluation in problematic samples. Real-world assessments often face critical problems regarding available data, as samples may be relatively small, with high variability in the magnitude of the observed indicators and contextual conditions. This paper explores the possibility of mitigating the impact of potential outlier observations and variability in small samples using a robust nonparametric approach. This approach has the advantage of avoiding unnecessary loss of relevant information, retaining all the decision-making units of the original sample. We devote particular attention to identifying peers and targets in the robust nonparametric approach to guide improvements for underperforming units. The results are compared with a traditional deterministic approach to highlight the proposed method's benefits for problematic samples. This framework's applicability in internal benchmarking studies is illustrated with a case study within the wastewater treatment industry in Portugal.

A system‐level optimization framework for efficiency and effectiveness improvement of wastewater treatment plants

“…The formulation of the DEA model underlying the assessment of the potential saving in energy consumption adopted the input–output specification proposed by Henriques et al. (2021). The DEA model seeks to minimize the energy balance given the pollutants removed (chemical oxygen demand [COD] and suspended solids [SS]) at the WWTP, as shown in Fig.…”

Water Pollution Early Warning Model Based on Decision Tree Algorithm and Electronic Information Technology

“…Uncertainty about pollution sources: It is difficult to determine the pattern of pollution impacts and the capacity for environmental damage because of the different types and quantities of pollutants that cause water pollution incidents. However, the type and quantity of pollution sources are important parameters for dealing with water pollution incidents and mathematical modelling of water quality [9][10].…”