Multicriteria Evaluation of Urban Regeneration Processes: An Application of PROMETHEE Method in Northern Italy

Table 3

Strengths and limitations of the proposed evaluation methods and relative results from the city of Collegno case study.

Evaluation method	Strengths and Limitations	Results from the city of Collegno case study
SWOT Analysis	+ Improvement of overall understanding of the decision problem general framework; + Provision of a systematic approach to analyse and decompose complex problems; + Identification of correlation between internal factors, strengths and weaknesses and external factors, opportunities and threats; + Ease of use and understanding of results; − Open nature and unstructured method; − Preliminary level of analysis; − Tendency to overemphasize opportunities; − Lack of prioritisation of factors (no requirement for their classification and evaluation); − Risk of oversimplification; − Risk of over-subjectivity in the generation of factors	The SWOT Analysis allowed the definition of the guidelines for the design and implementation of the general masterplan as well as the identification of the transformation process layout. It played a key role in supporting experts and planners in the identification of alternative scenarios for urban transformation/regeneration.
Stakeholders Analysis	+ Improvement in stakeholders management and mobilization of their support in achieving a goal; + Identification of purpose and time-dimension of interest; + Identification of time-frame and resource availability; + Provision of comprehensive analysis meant to produce new knowledge about policy-making processes; + Prediction or encouragement of stakeholder alliances; − Need for great reliance on quantitative approaches to data collection; − Need for iterative processes in data collection and analysis; − Inappropriateness of feedback of results when stakeholders may influence or control analysis results; − Uncertainty over validity and reliability of results; − Potential biases generated by analysts who become implicitly stakeholders who bring to the analysis their own values, perspectives and problem understanding	The Stakeholders Analysis provided the identification of relevant actors in the transformation and relative values and perspectives. These actors are mostly private investors and developers, who have financial resources available for undertaking investments and carry out the urban regeneration process. The Municipality of Collegno and the social groups involved in the process proved to be relevant actors as well.
PROMETHEE Approach	+ Ease of use; + Provision of a complete ranking; + Accuracy of results; + Adoption of the concordance non-discordance principle in the definition of the overall preference index; + Limited total compensation between pros and cons; + No assumption on the requirement of criteria to be proportionate; +Avoidance of the commensurability problem; − Non triviality in preference structuring in detail; − Assignment of weights that does not build on a clear method; − No information on the cost-effectiveness or profitability of alternatives (are they welfare-maximizing?); − Assignment of values that does not build on a clear method; − Difficulties in selecting the generalized criterion functions and the associated thresholds for each criterion; − Computational limitations with respect to the number of decision alternatives	The analysis performed by implementing the PROMETHEE method allowed the comparisons of urban transformation alternative options and the identification of the best performing solution for the regeneration process. The results show that the considered sets of weights converge in ranking the “Sharing city” alternative as the most preferred option, and the “Green infrastructure” alternative as the second best option.