An innovative methodological approach for the analysis of the effects of urban interventions on property prices [Un approccio metodologico innovativo per l’analisi degli effetti degli interventi di trasformazione urbana sui valori immobiliari]

The evaluation of the effects that an urban interventiongenerates on the area in which it is realized, and moregenerally on the city-system, plays a central role in thedefinition of its effectiveness, as it measures the effectsthat may derive from its implementation in terms of im-proving the quality level of the natural and built envi-ronment. The present research intends to propose andtest a methodological and operational approach to eva-luate, with quantitative indicators, the effects that anurban redevelopment initiative can have on propertyprices. In particular, the aim of the work concerns thedevelopment of a procedural protocol articulated intoclear and replicable phases, in order to support the ana-lysis of the urban transformation effects. The protocolis applied to four redevelopment projects currently inprogress, located in four municipal trade areas in thecity of Bari (Southern Italy). For each urban area, a sam-ple of two hundred residential properties sold in the pe-riod 2017-2019 has been collected. The implementationof a genetic algorithm has allowed the definition of theeconometric price function, able of identifying the setof variables - intrinsic and extrinsic – which, in each ofthe four intervention areas, contributes to the formationof property prices in the “ante-project” situation. Theanalysis of the effects of urban redevelopment in termsof variation of the urban quality has been carried out.Through an exogenous approach based on the inter-view of experts and community individuals, the valuesof the factors related to the urban quality following theimplementation of the projects have been determinedagain (“post-project” situation). By inserting the new va-lues into the econometric price functions alreadyfound, the market values of the post-project situationhave been estimated. The comparison between ex anteand ex post market values shows the increase in pro-perty prices following the redevelopment initiative andallows to quantify it, confirming the full consistencywith the expected empirical trends.