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POLITECNICO DI TORINO Repository ISTITUZIONALE Switching intentions towards car sharing - Analysis of the relationship with traditional transport modes Original Switching intentions towards car sharing - Analysis of the relationship with traditional transport modes / Ceccato, Riccardo. - (2020 Jul 03), pp. 1-356. Availability: This version is available at: 11583/2840371 since: 2020-07-16T08:41:33Z Publisher: Politecnico di Torino Published DOI: Terms of use: Altro tipo di accesso This article is made available under terms and conditions as specified in the corresponding bibliographic description in the repository Publisher copyright (Article begins on next page) 04 August 2020 Doctoral Dissertation Doctoral Program in Civil and Environmental Engineering (32th Cycle) Switching intentions towards car sharing Analysis of the relationship with traditional transport modes Riccardo Ceccato * * * * * * Supervisor Prof. Marco Diana Doctoral Examination Committee: Prof. A.B. , Referee, University of…. Prof. C.D. , Referee, University of… Prof. E.F. , Referee, University of…. Prof. G.H. , Referee, University of… Prof. I.J. , Referee, University of…. Politecnico di Torino Month Day, Year This thesis is licensed under a Creative Commons License, Attribution - Noncommercial - NoDerivative Works 4.0 International: see www.creativecommons.org. The text may be reproduced for non-commercial purposes, provided that credit is given to the original author. I hereby declare that the contents and organisation of this dissertation constitute my own original work and does not compromise in any way the rights of third parties, including those relating to the security of personal data. ………………………………..... Riccardo Ceccato Turin, Month Day, Year Summary Nowadays car sharing is widespread in several countries; in particular, in Italy, it has been introduced since few years. Advantages of this mean were estimated and reported by many authors. Car sharing can potentially reduce the number of owned cars, the number of performed trips and the relative distance, partially decreasing traffic congestion. Moreover, it contributes to a reduction in energy consumption of travelling, especially through the introduction of electric vehicles in the fleet. However, the quantification of these impacts is often difficult and uncertain. In addition, car sharing can significantly alter the modal share of travellers, since it can substitute or complement existing travel means, with relationships that are still not clear and often site-specific. Previously described benefits can be effective only if car sharing is able to attract private car drivers and, therefore, if it does not substitute other existing sustainable modes (such as public transport, bike and walking). Therefore, estimating and analysing travel demand of this mode is important to evaluate these impacts, thus providing sound basis to policy makers and local authorities, who have to decide whether to address public resources to promote car sharing and to provide travellers with a range of mobility options which can accommodate all their mobility needs. The aim of the present work of thesis is to identify factors affecting the choice to adopt car sharing and to analyse the relationships of complementarity and/or substitution between car sharing and existing travel modes. Unlike previous works, the effect of car sharing is modelled by separately considering the shift from private car, public transport, bike and walking. Therefore, through the proposed approach, the use of car sharing can be promoted or avoided, by varying mode-specific factors. In the present work of thesis, data from a travel survey carried out in the Turin Metropolitan Area are used. The survey was administered to a representative I sample of the population living in the study area, thereby outcomes of analysis can be generalized to the whole universe of individuals in the area under analysis. Socio-economic characteristic of respondents, their travel diary and related activity patterns spanning over the 24 hours before the interview were collected. Moreover, stated-preference experiments were administered to investigate mode switching attitudes for a randomly selected trip chain, which was effectively performed by the interviewed, thus allowing to obtain reliable results. In order to reach the aim of the present work, statistical analysis, discrete choice models and data mining techniques are adopted. In particular, first statistical methods are applied to preliminary analyse results of the travel survey, depicting an overview of the current reported scenario. After that, two logistics regressions are implemented, in order to identify users’ characteristics that might affect the choice to join a car sharing program and to understand how the characteristics of potential users of car sharing interact with both trip attributes and past and future multimodality behaviours. Then, in order to predict potential trips carried out on car sharing and to analyse which factors might affect the decision to switch to this mode, three kinds of approaches were developed: a traditional econometric model (a logit model), a data mining technique (Decision Tree model), and a descriptive visual approach. The three proposed methods differ in their basic assumptions; therefore, each approach faces the problem from a different perspective, whereby many results were obtained enriching the analysis about switching intentions towards car sharing. Results of the proposed approaches are complementary and others are common. In particular, the visual approach provided preliminary descriptive analysis on the effect of trip attributes. Moreover, logit models were helpful to understand the effect of different exogenous variables and to derive further information to forecast the consequences of the introduction and diffusion of car sharing on future scenarios. On the other hand, results from Decision Trees were used to identify the non-continuous effects of different variables, by estimating specific thresholds for each factor. However, an overall view of the results of the methods is useful to identify the best ambit of use of each travel means, namely the characteristics of trips which best fit to a specific mode. In this way, it is possible to clarify how car sharing can be effectively introduced to maximize its positive impacts. In addition, alternative mobility scenarios are generated using the estimated models, in order to maximize the number of trips switching from private car towards car sharing and minimize those from public transport and active modes. The results of each scenario are used to analyse the modal split and the effect of car sharing in the use of public space. II Sintesi Oggigiorno diversi servizi di car sharing sono largamente diffusi in molti Paesi; in particolare, in Italia, sono stati introdotti da pochi anni. I vantaggi derivati dal suo utilizzo sono stati stimati e descritti da vari autori: il car sharing permette, ad esempio, di ridurre le auto privatamente possedute, il numero e la distanze dei viaggi compiuti, favorendo, in tal modo, una minor congestione nelle strade. Oltre a ciò, può contribuire alla riduzione del consumo di energie non rinnovabili utilizzate negli spostamenti, soprattutto grazie alla presenza di veicoli elettrici nella flotta. Tuttavia quantificare tali impatti risulta molto spesso difficoltoso e con risultati incerti. Inoltre, l’introduzione del car sharing può alterare significativamente la ripartizione dei modi di trasporto normalmente utilizzati, dato che questo servizio può potenzialmente sostituire o essere di complemento a tali mezzi, anche se queste relazioni non risultano ancora chiare e dipendono spesso da fattori puntuali, con effetti diversi a seconda del luogo analizzato. I vantaggi precedentemente citati possono verificarsi solamente se il car sharing riesce ad attrarre utenti dal trasporto privato, senza sostituirsi ad altri mezzi più sostenibili, come il trasporto pubblico, la bici o il muoversi a piedi. Per queste ragioni, la stima e l’analisi della domanda di mobilità dei servizi di car sharing risulta necessaria per valutare correttamente gli impatti da essi prodotti. In questo modo le autorità e i decisori pubblici possono avere a disposizione dei solidi strumenti di supporto per indirizzare le risorse della collettività per promuovere o disincentivare l’uso del car sharing, e per fornire agli utenti del sistema un ventaglio di servizi di trasporto che permetta loro di soddisfare ogni esigenza di mobilità. Lo scopo di questa tesi è di identificare quali sono i fattori che influiscono sulla scelta di utilizzare il car sharing e di analizzare le relazioni di complementarietà o di sostituzione tra tale mezzo e i modi di trasporto esistenti. A differenza degli studi precedenti, gli impatti del car sharing sono stimati considerando separatamente III l’auto privata, il trasporto pubblico, la bici e il muoversi a piedi. In questo modo, l’uso dei veicoli condivisi può essere incentivato o meno agendo su variabili diverse per ciascun mezzo considerato. In questa tesi sono stati utilizzati dati derivanti da un’indagine di mobilità realizzata nell’Area Metropolitana di Torino. Tale questionario è stato somministrato ad un campione stratificato statisticamente rappresentativo della popolazione residente nell’area di studio; in tal modo, i risultati delle successive analisi possono essere espansi all’universo. Attraverso questa indagine sono state rilevate le caratteristiche socio economiche degli intervistati,