Search results

Negli ultimi anni molte città europee hanno introdotto politiche di tariffazione come strumento di gestione della domanda di trasporto, in particolare per ridurre la congestione e riequilibrare la ripartizione modale tra trasporto individuale e collettivo. Infatti, il comportamento degli utenti conduce il sistema ad una condizione di Equilibrio dell'Utente (User Equilibrium) che non corrisponde alla massimizzazione dell'utilità globale e non prende in considerazione i costi esterni. Pertanto, al fine di raggiungere una configurazione efficiente nell'utilizzo dei sistemi di trasporto (indicata in letteratura come Equilibrio del Sistema – System Equilibrium), è necessario imporre una tariffazione sulle strade urbane in modo da massimizzare il surplus sociale. Per numerose ragioni (teoriche, politiche, sociali) è impossibile applicare "tariffe efficienti" (indicate in letteratura come first-best solutions); perciò sulle reti reali bisogna applicare tariffe sub-ottimali (second-best solutions). Inoltre, una delle problematiche principali dell'applicazione delle politiche di pricing è la loro "accettazione" da parte della comunità e/o di sue componenti (commercianti, residenti, pendolari, ecc.) che conduce a conflitti ed opposizioni.In questa nota, si analizza il problema del progetto delle tariffe ottimali nel caso in cui i ricavi siano investiti totalmente o parzialmente per migliorare il trasporto collettivo. In particolare, si formula un modello che sia multimodale e multiutente, in cui gli aspetti relativi alla scelta modale siano calcolati in maniera esplicita su rete in corrispondenza di ciascuna configurazione tariffaria. Il modello è applicato ad una rete test (costruita con differenti valori di accessibilità relativa tra le differenti zone), analizzando alcune strategie "second-best" con particolare riferimento al reinvestimento dei ricavi. ; In recent years several European cities have introduced pricing policies as a tool for managing transport demand, especially to reduce traffic congestion and rebalance the modal split between private vehicles and mass-transit systems. Indeed, user behaviour brings about a User Equilibrium condition which does not correspond to overall utility maximisation and fails to take account of external costs. Hence, in order to achieve the efficient use of transportation systems (System Equilibrium), tolls can be charged on urban roads so that the social surplus is maximised. For several reasons (theoretical, political, social acceptability) it is impossible to charge "efficient tolls" (first-best solutions) proposed in the literature; therefore in real networks sub-optimal tolls (second-best solutions) are applied. Moreover, one of the main problems related to pricing policy application is their acceptability among community and/or social categories (such as shopkeepers, residents, commuters, etc.) leading to conflicts and oppositions.In this paper we analyse the effects on optimal fare design when pricing revenues are wholly or partly used for improving public transport. In particular, we formulate a model according to economic theory in a multimodal and multiuser context, where multimodal features are calculated explicitly on the network for each fare configuration. The model is applied on a trial network (built with heterogeneous values of relative accessibility among different traffic zones) and several second-best strategies are analysed with particular attention to the use of pricing revenue.

Negli ultimi anni molte città europee hanno introdotto politiche di tariffazione come strumento di gestione della domanda di trasporto, in particolare per ridurre la congestione e riequilibrare la ripartizione modale tra trasporto individuale e collettivo. Infatti, il comportamento degli utenti conduce il sistema ad una condizione di Equilibrio dell'Utente (User Equilibrium) che non corrisponde alla massimizzazione dell'utilità globale e non prende in considerazione i costi esterni. Pertanto, al fine di raggiungere una configurazione efficiente nell'utilizzo dei sistemi di trasporto (indicata in letteratura come Equilibrio del Sistema – System Equilibrium), è necessario imporre una tariffazione sulle strade urbane in modo da massimizzare il surplus sociale. Per numerose ragioni (teoriche, politiche, sociali) è impossibile applicare "tariffe efficienti" (indicate in letteratura come first-best solutions); perciò sulle reti reali bisogna applicare tariffe sub-ottimali (second-best solutions). Inoltre, una delle problematiche principali dell'applicazione delle politiche di pricing è la loro "accettazione" da parte della comunità e/o di sue componenti (commercianti, residenti, pendolari, ecc.) che conduce a conflitti ed opposizioni.In questa nota, si analizza il problema del progetto delle tariffe ottimali nel caso in cui i ricavi siano investiti totalmente o parzialmente per migliorare il trasporto collettivo. In particolare, si formula un modello che sia multimodale e multiutente, in cui gli aspetti relativi alla scelta modale siano calcolati in maniera esplicita su rete in corrispondenza di ciascuna configurazione tariffaria. Il modello è applicato ad una rete test (costruita con differenti valori di accessibilità relativa tra le differenti zone), analizzando alcune strategie "second-best" con particolare riferimento al reinvestimento dei ricavi. ; In recent years several European cities have introduced pricing policies as a tool for managing transport demand, especially to reduce traffic congestion and rebalance the modal split between private vehicles and mass-transit systems. Indeed, user behaviour brings about a User Equilibrium condition which does not correspond to overall utility maximisation and fails to take account of external costs. Hence, in order to achieve the efficient use of transportation systems (System Equilibrium), tolls can be charged on urban roads so that the social surplus is maximised. For several reasons (theoretical, political, social acceptability) it is impossible to charge "efficient tolls" (first-best solutions) proposed in the literature; therefore in real networks sub-optimal tolls (second-best solutions) are applied. Moreover, one of the main problems related to pricing policy application is their acceptability among community and/or social categories (such as shopkeepers, residents, commuters, etc.) leading to conflicts and oppositions.In this paper we analyse the effects on optimal fare design when pricing revenues are wholly or partly used for improving public transport. In particular, we formulate a model according to economic theory in a multimodal and multiuser context, where multimodal features are calculated explicitly on the network for each fare configuration. The model is applied on a trial network (built with heterogeneous values of relative accessibility among different traffic zones) and several second-best strategies are analysed with particular attention to the use of pricing revenue.

In recent years several European cities (such as London, Stockholm and Milan) have introduced pricing policies as a tool for managing transport demand, especially to yield a temporal, spatial and modal redistribution of travel, and particularly rebalance the modal split between private vehicles and mass-transit systems. Indeed, the interaction between user behaviours (whose choices are affected by transportation network performances) and transportation networks (whose performances are depending on the number of travelling users/vehicles) brings the system about a condition, defined in the literature as User Equilibrium, which does not correspond to overall utility maximisation and fails to take account of external costs. The discrepancy between the User Equilibrium condition and the efficient use of transportation systems (condition indicated in the literature as System Equilibrium) comes from user behaviour in making mobility choices: an additional user, entering a traffic flow, considers a travel cost that does not include the cost increase imposed on the other travellers in the network. In other words, travellers try to maximise their own utility or private benefits instead of considering social welfare. It is shown that efficient transportation system use can be achieved by charging 'efficient tolls' on network links. The optimal situation can be reached by the imposition of a tax (or toll) that will reconcile the private cost and the social cost. These tolls, called Marginal Social Cost Pricing (MSCP) tolls, are equal to negative externalities (such as congestion cost, travel delays, air pollution, accidents) imposed on other travellers by an additional user and are one of the most popular tools for pricing applications. For several reasons (theoretical, political, social acceptability) it is impossible to charge "efficient tolls" (first-best solutions) proposed in the literature; therefore in real networks sub-optimal tolls (second-best solutions) are applied. Moreover, one of the main problems related to pricing policy application is their acceptability among community and/or social categories (such as shopkeepers, residents, commuters, etc.) leading to conflicts and oppositions. In this paper we analyse the effects on optimal fare design when pricing revenues are wholly or partly used for improving public transport. In particular, we formulate a toll computation model through a multidimensional constrained optimisation problem according to economic theory in a multimodal and multiuser context, where multimodal features are calculated explicitly on the network for each fare configuration. The model is then applied on a trial network (built with heterogeneous values of relative accessibility among different traffic zones) and several secondbest strategies are analysed with particular attention to possible effects of road pricing revenue use on social welfare and fare levels.