Hindawi Advances in Operations Research Volume 2018, Article ID 2806062, 16 pages https://doi.org/10.1155/2018/2806062

Research Article Integration between Transport Models and Cost-Benefit Analysis to Support Decision-Making Practices: Two Applications in Northern

Paolo Beria ,1 Alberto Bertolin ,1 and Raffaele Grimaldi 2

1 DAStU, Politecnico di Milano, Via Bonardi 3, 20133 Milano, Italy 2Independent Researcher, Milano, Italy

Correspondence should be addressed to Alberto Bertolin; [email protected]

Received 22 December 2017; Accepted 18 March 2018; Published 23 May 2018

Academic Editor: Marta Bottero

Copyright © 2018 Paolo Beria et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Decisions on transport plans and projects involve relevant public investments and may also determine radical changes in users’ costs. Unfortunately, it is not rare that—especially at the strategic planning stage—decisions on alternative projects or scenarios are made on a qualitative basis or, at best, by setting some indicators and verifying how much they reach the politically decided targets (e.g., “increasing the use of bicycles by 10%”). In order to reduce subjectivity, a more quantitative and comprehensive approach to the evaluation is needed. A Cost-Beneft Analysis is a tool commonly used to assess public expenditure, but its application to mobility plans introduces further practical and theoretical complexities. In this paper, we will thus try to contribute to the topic of the assessment of both sustainable mobility transport plans and infrastructure projects by presenting the operative application of a CBA methodology that is, at the same time, theoretically coherent and rich in outputs to support the decision-maker. Moreover, we will discuss the possible use of GIS sofware in order to provide to the decision-makers a clear and immediate “picture” of the efects on the network linked to diferent scenarios. Te structure is as follows. Firstly, we discuss the complexities involved in the evaluation of plans with respect to a single infrastructure. Secondly, we introduce the available approaches for the assessment of consumer surplus, namely, the Rule of Half and the logsum function method, which allow the perfect integration between CBA and transport models. Tirdly, we present, through some operative case studies, the methodologies applied to the assessment and the network efects visualization of the urban mobility plan and new infrastructures. Finally, we underline how we can make the results more understandable to politicians, policy-makers, stakeholders, and citizens and in general improve the transparency and the awareness of the choices.

1. Introduction: Evaluating Transport Plans the promotion of city walkability, the development of bike and Infrastructural Projects transport, road pricing, park pricing, technological invest- ments on networks, vehicles, and communications, smart Modern transport plans try to achieve diferent objectives mobility, vehicle sharing projects, incentives, redefnition of and, in general, try to obtain a more sustainable and inclusive fares structure, mobility credits, and so on. [1, 3, 4]. transport system, as suggested by the recent European Sus- When performing the evaluation of such complex plans, tainable Urban Mobility Plans (SUMPs) guidelines [1]. Tis is a mismatch occurs between the available assessment tech- usually done by foreseeing, simultaneously, the improvement niques and the contents and expectations of plans. In fact, of existing transport services and infrastructure, together the economic evaluation of transport investments is usually with the implementation of sustainable mobility policies. intended in terms of assessment of transport infrastruc- Tisalsoallowstakingadvantageofthebeneftsofpolicy ture, while plans include a broader range of actions, where packaging in terms of higher acceptability, efectiveness, and expected environmental and social impact can play a domi- efciency [2]. Among the available policies, we can recall nant role in policy evaluation [5]. 2 Advances in Operations Research

Table 1: Policy actions in a mobility plan and type of efect.

Investment costs are dominant versus Action/policy Costs Benefts other costs? New infrastructure (public transport, roads PU,T pr,C,t Yes capacity) New/modifed services on existing PU,t pr,d,t No infrastructure Innovative mobility (sharing, pooling, etc.) pr, d, t No Bicyclelanes,bikeparking,bikesharing PU,T pr,d,t Yes/No ITS, trafc management PU, t pr, d, t No Restrictive policies, car-free zones, trafc pr,d,t d,t No calming Parkandroadpricing pr,d,t PU,pr,d,t No Public transport fares PU/pr, d, t Pr/PU, d, t No PU: public bodies; pr: private users; C: concentrated in space or limited to groups; d: difused in space or spread among many users; T: punctual in time, lump sum; t: continuous in time.

Te mismatch lies also in the evaluation tools commonly which may be included and assessed in a complex urban used to support the design of mobility plans and the conse- mobility plan. quent public decisions, which are substantially referable to In plans, additive policies, such as new infrastructures whose costs are public and concentrated in time, coexist with (i) Traditional Cost-Beneft Analysis (CBA), required restrictive policies, such as trafc calming, pricing, and so on, practically everywhere to allocate public money for which changes mobility patterns through raising the private infrastructure investments, that is, in cases where costs. Tese two extremes must be assessed in a coherent way, thepublicdecisionisdominatedbythealternative but their efects and economic mechanisms are substantially allocation of lump sums [6–8]; diferent. (ii) Multicriteria analyses (MCA) and Indicators-based Moreover, the efects act synergistically, so that modal assessments, used to structure and clarify the goals shif is the efect of both the improvement of the destination and the (possibly positive) efects of the actions of a mode (e.g., public transport) and the worsening of the origin plan, such as the foreseen decrease in car ownership mode (e.g., private road transport). When the existence of or pollutants concentrations [9, 10]. such complex cost and beneft structures in the assessment In the assessment of a plan made of both “hard” (infras- of plans or projects is recognised, theoretical and practical tructural) investments and “sof” policies, both traditional problems may arise. As already mentioned, approaches using approaches may fail. In particular, a rigid CBA may not only indicators and MCA are not satisfactory for evaluating be able to catch all the efects of the plan [7, 8, 11, 12] the trade-ofs of public expenditure. At the same time, CBA in and, in addition, provides too concise outputs to support the “simple” form, as suggested by numerous guidelines (e.g., the dialogue with public opinion and stakeholders [13]. On [16, 17]), is not sufciently complex to handle the previously the other side, indicators and MCA are, by defnition, not mentioned problems and, in addition, fails in efectively able to measure the efciency of public expenditure, which representing the distribution of efects [18], especially for represents a key element of public decisions [7, 8]. Some non-win-win policies. EU members state that, in order to include nonmonetized Lastly, especially when CBAs are implemented to inves- impacts in infrastructure projects or policy evaluation, they tigate complex transport scenarios, problems can arise from optedforMCAinwhichaCBAiscontained[14,15]. the imbalance between expert knowledge and various stake- Moreover, one must consider that the “typical” scheme holders’ expectations on their “pet-projects” [13]. In order to of lump sum public costs versus distributed private benefts promote a constructive dialogue in the decision-making pro- is not always the case, especially with pricing or limitation cess, not only must CBAs be rigorous from a methodological policies. In these cases, the policy gives both advantages to point of view, but also their fnal and, possibly, intermediate some groups (e.g., public transport users) and disadvantages resultshavetobebothintuitiveandefectiveforageneral to others (e.g., car drivers), in some cases entailing no audience. signifcant public expenditure. A decision on this kind of For such reasons, in this paper, we will contribute to the policy, which is not simply “adding” new transport supply topic of decision-making for complex plans and projects in a for someone, should obviously take into account not only the threefold way: benefts, but also the public and the private costs necessary to (a)Howtomanagetheconsumersurplusfromatheoret- obtain them. ical viewpoint. While theoretical literature on meth- Table 1 provides an example of possible policy actions, ods is mature and clear, it does not appear helpful with diferent spatial and time boundaries of their efects, from the point of view of practical applications. On Advances in Operations Research 3

the other side, guidelines are ofen too simplistic to handle complex problems, or even misleading. (b) How to practically calculate the consumer surplus for both a mobility plan and an infrastructural project ＃＇1 basedontransportmodeloutputs. C (c) How to enrich the outputs of the evaluation in order to make the assessment useful to inform decision- makers’ choices. ＃＇2 Tepaperisstructuredasfollows.Section2discussesthe two correct ways to calculate consumer surplus, the Rule of Q Q Half and the logsum function method, underlining both their 1 2 Q pros and cons and in which situations they are recommended. Section 3 illustrates how these two methods can be calculated, Figure 1: Representation of the Rule of Half (our elaboration). in practice, by means of a transport simulation model, and how to modify the general formula when an active mode is included in simulations. Section 4 presents two evaluation cases: ’s Sustainable Urban Mobility Plan and the Milan Malpensa airport rail ring closure. Section 5 associates with his overall trip experience, including out-of- concludes. pocket expenses (tolls and fares), operating costs of vehicles (in private transport), and consumed time. Other factors like discomfort, crowding, landscape, and more personal atti- 2. Calculating the Consumer Surplus tudes can also reduce or increase the GC of the same trip for CBA is a widely used and codifed technique. Te transforma- diferent users (in the paper, we refer to the calculation of user tion into monetary values of the majority of variables taken surplus in terms of perceived (or private) costs, which—as intoaccountintheanalysiscanbedoneinanintuitiveway we discussed in a former working paper [20]—requires some (investment costs, running costs, environmental benefts, corrections to balance transfers (e.g., taxes and fares) among taxation, etc.; see, e.g., [16, 17]), but we cannot say the same diferent parts of society; another relatively widespread for the consumer surplus. Tis component, especially when approach, especially when the GC comparison is used, is to related to complex plans, may be misleading and concurring calculate the variation in user surplus directly in terms of in the introduction of double counts or internal incoherencies social costs; the considerations made in this paper remain [19, 20]. valid). Many guidelines indicate three possible approaches to Tus, intuitively, the variation between the GC before and estimate the consumer surplus. In practice, their application afer a project or policy implementation will return the gain is seldom discussed and the responsibility to choose among or loss in beneft (surplus) for a specifc user even when he them is lef to technicians. For example, in Italy the guideline shifs between diferent means of transport. provided by the Ministry of Transport [21] does not suggest Unfortunately, information on the single user trip expe- the application of a specifc method to calculate user surplus, rience is not always available. More realistically, when avail- while the Region guidelines defne the Rule of Half able, we can use a transport model to obtain the average method as mandatory to evaluate infrastructural projects generalised costs of groups of users (see Section 3), also in [22]. Nevertheless, the three methods return results that are a very detailed way. Te problem that arises is how to treat not always comparable. In particular, the simplest approach, shifing users knowing only the GC average value and the the generalised costs comparison, has results that are ade- total quantity of users in each group. quate only under very specifc and seldom-present conditions Traditionally, the most robust and used method to calcu- [23]. Te other two methods ensure a diferent level of late the variations in user surplus when a transport model is robustness and precision and require diferent amounts of not available is to hypothesize the unknown demand curve as data but can both be suited to almost any application. In the a linear function between two points. Tese points, which are following, we will illustrate these two latter methods, and we always known, are codifed by the intersection between GCs will underline when they are almost perfectly substitutable and the total amount of users (�) before and afer the project and when; on the contrary, we can expect considerably implementation [16, 19, 20]. diferent outputs. Tis hypothesis allows the application of the so-called Rule of Half. Te area of the rectangle having base �1 2.1. Te Rule of Half (RoH) Method. Te consumer surplus (the number of existing users) and height GC1 − GC2 (the is defned as the diference between user willingness to pay reduction in generalised costs, that is, the unit beneft) to make a specifc trip and the “price payed” to make it represents the surplus variation of existing users. Similarly, [24]. In transport, the “payed price” by each user to make thesurplusofgeneratedorshifedusersisgivenbythearea a specifc trip is codifed in the so-called generalised cost of the triangle having base �2 −�1 (the number of new users) (GC). Te GC represents the monetary value that the user and the same height GC1 − GC2 (Figure 1). 4 Advances in Operations Research

Te variation in user surplus is thus given by the area of a used in calibration) for the users travelling for the purpose trapezius as in (1) (hence the name “of half”): group [�].

� ⋅ 1 � � GCod|�|� Δ� =(�)×( − )+ (� −� ) users 1 GC1 GC2 2 1 � |�|� = . (2) 2 od ��⋅GC |�|� ∑� � od ×( − ) GC1 GC2 (1) Tus, the unitary surplus variation is equal to the diference 1 in the composite utility (given by the logarithm of the denom- Δ� = (� +� )×( − ). users 2 1 2 GC1 GC2 inator of the logit formula (thus the name, “logsum”), divided by the calibration parameter), before and afer projects and/or Due to its simplicity and the relatively reduced amount of policies implementation. Once we multiply this unitary value data needed in the formula, this approach is very widespread. for the number of trips related to each single purpose, we Any other method requires both estimating the GCs’ absolute obtain the user surplus variation linked with that trip purpose values, a much more difcult task, and knowing the GC [Δ�] [25, 28–30] (Bates [31] states that “with a logit model, of “origin” modes (the estimation of the absolute value of there is a closed form solution for the integral under the demand generalised costs is not a simple exercise without a transport curve,” which is the surplus). model, especially in public transport and in active modes Δ� (walking and cycling); the related variation is instead usually od|� made only of easily measurable items, like time savings 1 and/or operating costs). = trips� ⋅ �� (3) Moreover, this method, by treating the whole of induced users (i.e., both generated and shifed from other modes, � ⋅ � ⋅ ⋅[(ln ∑ � � GC1,od|�|� )−(ln ∑ � � GC2,od|�|� )] . paths, time of the day, etc.) in the same way and not needing � � theabsolutevaluesoftheGCs,avoidsalltheproblems linked to the generalised costs comparison approach. Tese Tesumofthesevariationsforalltheusergroupsobviously problems are mainly determined by the impossibility of gives the total variation in consumer surplus associated with knowing the GC value for each single user [23]. the scheme or policy. If we expect generated demand to appear in the postpro- 2.2. Te Logsum Function Method. Te RoH assumes a ject scenario, and we want to keep using the logsum approach, certain distribution of users across average GCs. Depending Bates[31]suggestsapplyingtheRule of Half to the standard on the required level of detail (and, of course, on the available logsum formula (4): data), analysing, by disaggregating as much as possible users Δ� in homogenous groups (i.e., in terms of geography, trip od|� purpose, etc.) and applying the RoH to each group separately 1 1 = ⋅( + )⋅ can minimise the error equal to the distance between the trips1,� trips2,� 2 �� (4) single user GC and the average group value. Despite its methodology consistency, RoH returns an � ⋅ � ⋅ ⋅[(ln ∑ � � GC2,od|�|� )−(ln ∑ � � GC1,od|�|� )] . approximation of user surplus based on a “strong” prelimi- � � nary assumption: a linear distribution between demand and GCs. Despite being well-discussed in the literature quoted above, However, when a calibrated transport model is available, the logsum function method has been barely seen from an it is possible to use another method to assess the variation applicative point of view, when real projects and plans must in user surplus, which gives a much more detailed repre- be practically assessed. Te following part of this paper sentation of the benefts. By measuring, for all alternatives tries to go more deeply in this direction (a more detailed (modes), the variation in the composite utility (logsum) discussion on diferences between logsum and Rule of Half returned by the transport model, it is possible to calculate methods is presented in Mafi et al. [32], Cascetta [25], Geurs not only the average values of the GCs, but also their et al. [33], Grimaldi and Beria [20], and Bates [31]). implicit distribution among users, thus having a more precise variation in user surplus [25]. 3. Consistent Integration between Planning, Most transport models, in fact, estimate the share of users Modelling, and Assessment [�] that will choose a transport mode [�], on the origin- destination pair [od],forthetrippurpose[�],usingthe 3.1. Beneft from a Direct Integration of CBA and Transport multinomial logit formula described in (2) (if the model is Models. Te most complex aspect to model in a CBA is the based on a nested logit, this operation can be done on the demand curve and its relationship with the replaced assets frst (higher) level of the logit; the GC represents the disutility when generated demand is present. In the transport sector, of the trip) [26, 27]. Parameter [��] is a calibrated value the demand generated by a certain project is the sum of the that maximizes the probability that the expected (simulated) new demand induced by the lower transport cost (people who modal share is coherent with the observed value (real data now travel and who did not travel before, given their lower Advances in Operations Research 5 level of willingness to pay) and the demand attracted from is a way to overcome the issue, though with some loss of other means of transport. consistency (see, e.g., [34] or [29]). We divide the systematic Generally, transport problems are faced with four-stage utilitybythetimeparameter(whichisalwayspresent)instead multimodal models (guidelines from Lombardy Region [22, ofbythecostone,thusderivingageneralised time instead of p. 18] and the Italian Ministry of Transport [21, p. 30] defne the generalised cost. the use of multimodal transport models to evaluate infras- � od|�|� tructural projects as mandatory). Tese models allow both GT |�|� = . od �Time (7) the distribution of the existing and generated (induced and/or �|� attracted) demand between OD relations and, considering the relative generalised costs that determined the choices, the Ten we multiply this generalised time by an exogenous value calculation of users’ paths. of (in-vehicle) time (VoT), obtaining the generalised cost.

Within the four-stage models, the modal choice can GC |�|� = VoT ⋅ GT |�|�. (8) be assimilated to the application of a demand curve. A od od certain perceived cost (according to the CBA formulation) When the GCs are estimated, we can directly apply the or generalised cost (according to the modelling formulation), formulas of the surplus variation, discussed in Section 2. It corresponds to a certain quantity consumed. Terefore, the must be noticed that this passage is done at the highest level integration between models and CBAs allows greater preci- of disaggregation: per origin–destination pair (od),travel sion (ensured by the model) in determining the costs for all purpose (�), and mode (�). Tis is a computational burden, users on the entire network modelled (instead of considering involving even millions of operations if the study area is separately the users on specifc segments of the network) and divided into hundreds or thousands of zones, like in urban a perfect match between model and evaluation. or regional areas. However, this disaggregation allows for In conclusion, while without a model, the CBA must nec- enrichingthereadabilityandcompletenessofoutputs. essarily be based on rather strong assumptions (invariance of the demand or, in the case of demand generated or shifed, 3.3. Presenting the Results. In fact, a nonsecondary aspect assuming a linear trend for the demand curve); with a model, deals with the outputs of the analysis. Backing the surplus the descriptions of both demand and user surplus variation calculation methods with a calibrated model and working at will be much more detailed. Moreover, parameters such as the the origin–destination pair allows the representation of the value of time can be directly those of the calibrated model. benefts geographically, and not only in an aggregate way. Tis kind of representation may be a useful complement to the 3.2. Extracting Generalised Costs. When a transport model is aggregate CBA indicators (NPV, NBIR, B/C, IRR; [16]) both available, it is relatively easy to extract the GCs directly from in the consultation phase and, ultimately, in making better it, guaranteeing a complete consistency between the model decisions. and the following Cost-Beneft Analysis. Te GCs derived Indeed, the network efects visualization, thanks to a GIS this way can be used both with the Rule of Half and with the sofware, of a proposed project or policy allows for foreseeing logsum method. which parts of the territory (and, consequently, which citizen To obtain GCs, it is sufcient to extract the systematic groups)willgainorlosemoreifthatactiontakesplace. utilities used by the model, which is usually constructed like In the next section, we present the methodologies applied in (5)(with systematic utility � we mean, according to the for the assessment and network efects visualization of the defnition by Cascetta [25], “the mean or the expected value sustainable urban mobility plan of the Milan municipality of the utility perceived among all the users with the same (seeSection4.1)andtheproposedrailringoftheMalpensa choice context”; the perceived utility � is given by the sum airport (see Section 4.2). Due to their specifcities, for the of the systematic utility � and the random residual ¥ (which plan evaluation, we utilized the logsum method, which represents the deviation of the single user with respect to the assures that nonadditive policies do not bring the risk of average value): �=�+¥). double counts, and the RoH one for the rail project. � =�Time ⋅ +�Cost ⋅ od|�|� �|� Time �|� Cost (5) 4. Theory Application: Two Case Studies + . Other components 4.1. Milan’s Sustainable Urban Mobility Plan. For the assess- If we divide the systematic utility by the parameter related ment of the new Milan’s Sustainable Urban Mobility Plan to its monetary component, we express it in monetary terms [35] we interfaced the simulation model developed by the representing the monetary trade-of that users attribute to transport authority (AMAT), with the assessment procedure, their trips, which is the GC. based on the interaction between a database and spreadsheet sofware. Te transport model has been used extensively � = od|�|� . in the past years to plan all transport decisions in the city GCod|�|� Cost (6) ��|� and can rely on solid datasets of observations, used for the calibration. Not only CBA, but also Te Strategic Environ- Sometransportmodesmightnotbeassociatedwithany mental Assessment of Milan’s SUMP was based on the same direct monetary component (e.g., walking and cycling). Tere transport model outputs. However, these two evaluations 6 Advances in Operations Research

Tables of Attributes (generalised Multimodal transport Calculation of surplus time), of Quantities (users per model (AMAT) variations, total and mode) and of transfers (fares, etc.) per zone [SQL DB] estimated for each O/D couple

Map representation of surplus Tables of surplus variations, variations, of travel time and of time, and of quantities, per passengers [GIS] zone

＃＇1 C

＃＇2 Q Q Aggregated surplus variations 1 2 Tables of surplus variations, Q [Spreadsheet] of time, of quantities, total

Figure 2: Te assessment procedure implemented for the Milan’s Sustainable Urban Mobility Plan (SUMP).

difer for some assumptions on input data (e.g., CBA, in the parking tolls, the road pricing tolls, the driven km (useful the environmental efects calculation, considers, for the year to calculate the fuel duties paid). 2024, an equal distribution between the total number of Overall, the output consists of a database fle with Euro V and VI vehicles, while the latter defnes the vehicle’s tables of attributes (generalised time), quantities (amount feet starting from a regression model on gasoline sale of users), and transfers (fares, tolls, and taxes) per 390,452 trends). However, the overestimation “error” magnitude is origin–destination pairs and 24 (4 × 6) mode and travel contained and does not afect the overall CBA result [36, pag. purpose combinations. By means of SQL procedures, we 112]. estimated the surplus variation using the logsum method A schematic representation of the algorithm developed (as described in Section 2.2). It must be noticed that the for SUMP scenario’s assessment is depicted in Figure 2. corecalculationsaredoneatthehighestdisaggregationlevel, Te transport model provided the generalised cost com- that is, per OD pair, mode, and travel purpose. Later, we ponents of each origin–destination (OD) pair for fve difer- proceeded with the aggregation of the results in 829 origin ent travel purposes (plus the “back-to-home” purpose) and and destination zones, using the same zoning of the model. forfourmodes(car,motorbike,publictransport,andactive Te same thing has been done for all attributes, quantities, modes). Each segment of the simulated mobility is associated and transfers. with a set of calibrated � coefcients (5), including the values Once the aggregation is done, the datasets become more of time (per trip purpose and per mode). In addition, the manageable with other sofware programs. Te procedure is model provides the quantities, in terms of passengers/users then interfaced with a spreadsheet sofware for the CBA and during the peak hour, for every mode on each OD pair, with a GIS sofware to produce cartographical representa- allowing us to calculate the mode-shifing users. Finally, the tions of the main variables. model output also includes the data used to correct the Te entire process has been applied for 51 explorative sce- monetary transfers in the CBA, in particular the paid fares, narios. For this reason, we put particular care into automating Advances in Operations Research 7

COST BENEFIT ANALYSIS

ECONOMIC CBA FINANCIAL CBA

Investment and maintenance costs Investment and maintenance costs Running costs (& savings) Running costs (& savings) User benefts (cost & time savings, crowding Revenues from park and road pricing; fuel duties reduction, congestion reduction) Environmental benefts (local pollution, CO2, noise) Health benefts for active modes Safety benefts (& disbenefts) Revenues from park and road pricing; fuel duties Opportunity cost of public funds

+ DISTRIBUTIVE ANALYSIS + SENSITIVITY ANALYSIS

How C&B are distributed among users groups How CBA results change at the variation of some How C&B are distributed in space input parameters

Figure 3: Cost-Beneft Analysis components.

the procedure with scripts. At the same time, we track all the Table 2: SUMP explorative scenarios. intermediate results throughout every step to facilitate debug Number of subscenarios procedures. Some controls have been introduced intermedi- Explorative scenario (alternative options) ately to manually check the correctness of the results. Te Previous land use plan (PGT) processalsopointedoutsomelocalinconsistenciesofthe 3 transport model, which have been corrected. infrastructure Te CBA has been done within a spreadsheet sofware, in Metro line 1 extension 3 the two variants of Economic CBA and Financial CBA. Te Metro line 2 extension 5 elements included are listed in Figure 3, and the indicators Metro line 3 extension 3 calculated are the Net Present Value (NPV), the Net Beneft Metro line 4 extension 4 over Investment Ratio (NBIR), and the Beneft over Cost Metro line 5 extension 3 Ratio (B/C). In addition, we also developed in the same environment New Metro line 6 3 (explorative paths) the distributive analysis module (disaggregating the costs and Tram 7 extension 4 the benefts into six user categories, plus the nonusers, the Tram 24, 27, and 178 extensions 2 + 2 + 1 State, and the Local Administration) and a simple Sensitivity Reorganisation of tram lines in the city 1 Analysis, testing automatically the efects of user surplus centre estimation, investment cost, and running costs on results. New urban stations to support rail 7 Te CBA, shortly described here, was directly included in “circle line” services the planning process as suggested in European guidelines [1]. Change in a suburban rail line path 1 It is worth mentioning because this represents the frst case in Extensionofbikelanes 2 Italy. In fact, it was only in 2015 that the regional government, 30 km/h speed limit areas 1 within its guidelines, imposed the CBA as mandatory to assess transport projects [22] and, at the national level, this Road pricing (Area C) extension 4 Actions to increase commercial speed evaluation tool became compulsory one year later [21]. 2 of surface public transport 4.1.1. Scenarios. In a preliminary phase, planners, stakehold- ers, and politicians selected, among all the actions included in previous planning documents and/or indicated by citizens, 51 30 km/h speed limit areas). Table 2 provides an overview of explorative scenarios to be assessed via CBA. Tis preselec- all the scenarios considered in the analysis. tion was carried out by choosing, according to the political Te aim of this explorative evaluation was to identify goals,themostefectivealternativebetweencomparable those actions that returned positive CBA indicators or, in projects facing a single problem. case of negative performances, under which conditions it was Te selected policies and projects were heterogeneous possible to reduce their negative socioeconomic impact. For in nature, from heavy infrastructural investment (i.e., new example, in the case of the 30 km/h speed limit areas, negative metro lines) to punctual trafc calming solutions (i.e., indicators were returned when this action was assessed alone. 8 Advances in Operations Research

Figure 4: An example of Appraisal Summary Table organisation.

Tis intermediate result was a consequence of the reduction To do that, all the intermediate and fnal results of the in road capacity and, consequently, an increase in congestion scenarios were presented through the following outputs. and travel time for private vehicle users. However, the same (i) An Appraisal Summary Table,directlyinspiredbythe policy, evaluated in combination with other actions aimed at ones used in the UK [37] promoting a modal shif in favour of public transport, was associated with a positive impact in terms of user surplus. (ii) A Book of Maps, visualizing on a cartographic basis At the end of this explorative phase, all positively assessed the efects of the hypothesis on users’ behaviours and actionshavebeenincludedinthefnal Plan Scenarios and socioeconomic variables. evaluated together. Tis last scenario does not represent just a Te frst output included the socioeconomic assessment, the sum of all the positive/negative efects of the explorative ones, fnancial assessment, the distributive analysis, and a summary but takes into consideration the interdependency between the of the results complemented with some general comments diferent actions within them. (Figure 4). Duetothediferentnatureoftheactionstakeninto 4.1.2. Representing the Results. Tanks to the previously men- consideration, we provided a double version of the Net tioned procedure, we were able to draw semiautomatically Present Value (NPV), the Net Beneft over Investment Ratio the outputs for the numerous scenarios. Moreover, fnal (NBIR), and the Beneft Cost Ratio (B/C), calling them, documents and analyses clarify all the main aspects that respectively, “base” and “extended.” Te frst set is based should be considered for the decisions, not limited to the sole on a reliable quantifcation of all the monetized efects aggregate CBA indicators (NPV, NBIR, and B/C). Tis result related to the single scenario implementation (investment, is fundamental in order to simplify the decision process of user surplus, externalities, etc.). Te other set (extended), on City Council, allowing diferent stakeholders to potentially the contrary, was an attempt to quantify, from an economic revise their goals on the basis of a transparent and consistent viewpoint, efects related to “sof” mobility policies such as analytical process. health benefts for active modes, the opportunity cost of Advances in Operations Research 9 public funds, and an approximation of the possible wider Te main results of this new network were economic efects. In fact, in these cases, these aspects can be considered as the most relevant, and a CBA that does (1) an increase in user surplus of 209 M€/year; not include them is mainly incomplete. However, due to (2) a reduction in bus operating costs of 47.6M€/year; objective difculties in quantifying some of these efects, we (3) an increase in public transport revenues of introduce these indicators mainly to underline a possible 25.6 M€/year; positive or negative threshold in comparison with those of the frst set. For example, on health benefts related to bicycle (4) a reduction in negative externalities (accident, envi- users, diferent sources provide very variable values. From ronment, and climate change) of 12.1 M€/year. 0.03 €/km [38] up to 0.36 €/km [39] or 0.44 €/km [40]. For our analysis, we considered a weighted average value of 0.365 However, these apparently good outcomes are not capable €/km. Moreover, other nonmonetary elements were returned of counterbalancing the investment, operating, and main- only in a qualitative way (similar to what Sager [12] describes tenancecostsofthenewinfrastructureandservices.Te as a “narrow CBA”). Beneft/Cost ratio results are 0.80 for the conventional heavy metro version and 0.86 for the automatic light metro. Our aim, in fact, was to provide the decision-makers with Te fnancial impact for the public budget would exceed not only a synthetic “number” to quantify the goodness of an 330 M€/year. action, but also a set of tools, giving politicians a certain level of informed discretion on the fnal decision. In comparison, we tested a scenario based on a gener- alised speeding up of the entire overground (bus and tram) Te second output (Book of Maps) included, for each sce- public transport, mainly through trafc light coordination nario, 24 cartographies showing the variations, both in abso- and intersections redesign. Te interventions hypothesized in lute values and as a percentage, of user surplus, passengers the simulation consist of per means of transport, and travel times and distances. Data was aggregated once per zone of origins and subsequently on (1) an increase in the commercial speed of some tram line destinations, allowing a complete visualization of the network up to 18 km/h in the most congested part of the city; efects connected to single scenarios. (2) an increase of 10% in the commercial speed of all Tis detailed output allows us to depict, for example, that other bus and tram lines; users obtaining beneft from a metro or tram line extension are not only those citizens living or working next to it, (3) the reintroduction of 3 circular bus and tram lines butalsousersofotherzones,relatedtodiferentmeansof around the city centre; transport, benefting from road decongestion. Similarly, this (4) the implementation of the new peripheral tram line output is useful in directly visualizing the modal shif’s spatial in the northern part of the Milan municipality. extension. Tistoolisparticularlyefectiveinunderliningunbal- As for the PGT scenario, the result in terms of user beneft anced situations between diferent parts of the city (i.e., local was defnitely positive (221 M€/year), but the Beneft/Cost beneftor,onthecontrary,surpluslossduetopunctual ratio was outstandingly higher (above 15), considering an actions) and giving hints to policy-makers on how to address investment cost of 200 M€. specifc situations. From the distributive point of view, the traditional metro extension scenario (Figure 6) and the cheaper speed- 4.1.3. How Assessment Changed the Decisions. Tis approach up scenario (Figure 5) perform similarly. Te latter gives proved to be a fundamental support for the redefnition of homogeneous benefts to almost all zones of the city, while the strategic objectives of the public administration regarding the metro extension presents some more inhomogeneity, the new type of mobility to sustain the future growth of with some zones largely benefted and others just margin- the city. Trough the combination of the aggregate results ally. and benefts distribution maps, we were able to quanti- In conclusion, if the schematic goals of speeding up the tatively efect a change of vision for the decision-maker public transport network are actually realized, their efect from a traditional transport plan based on new “heavy” would be enormously positive and equal to that of six new underground infrastructures to a plan made of punctual high-frequency mass transit lines. Te margin of beneft of and cheaper actions homogeneously difused on the entire this scenario is such that even obtaining only a fraction of the Milanese public transport network. increase in commercial speed simulated can ensure a positive For example, the frst scenario considered the transport overall outcome. lines envisaged in the previous Milanese land use plan (PGT). Tis type of comparison is useful for testing, and poten- Tis huge plan hypothesized the creation of 6 new high- tially reorienting, decision-makers’ vision and strategies, on performance lines for a total length of 77.3km (56.1 km of which plans were founded. Also thanks to these comparative metro lines and 21.2 km of tram lines), providing one run results, City Council decided to renounce a growth based every 3 minutes per direction. In the evaluation, metro lines on new “heavy” and costly infrastructure and, nowadays, have been studied once as traditional heavy lines and once the Milanese transport authority is working on punctual as automatic lines, having a higher investment but lower interventions that are able to ensure higher overground operating costs. public transport commercial speeds. 10 Advances in Operations Research

Rescaldina Solaro Solaro Arcore Bovisio-Masciago Desio Lissone 2014 Villasanta Vimercate Paolo Beria, Rafaele Grimaldi Varedo Limbiate Concorezzo Nova Milanese Muggiò San Vittore Monza Agrate Brianza TRASPOL - LaboratorioVilla Cortese di PoliticaCanegrate dei Trasporti DairagoPolitecnico di Milano Caponago Brugherio Piano Urbano della Mobilità Sostenibile Rho

Vanzago Sc.: VelocizzInveruno TPL superficie (TPL_V1) Cassina de' Pecchi Pero

Milano

Bofalora sopra Ticino Corbetta

Magenta

Variations in user surplus - Origin [€ during peak hour]

more Robeccothan sul -130.0Naviglio -129.9 - -100.0 San DonatoMilanese -99.9 - -70.0 -69.9 - -40.0

-39.9 - -10.0

Zelo Surrigone -9.9 - 10.0 Opera 10.1 - 40.0 40.1 - 70.0 70.1 - 100.0 100.1 - 130.0 more than +130.0 Vernate

Figure 5: Variation in consumer surplus due to the generalised speeding up of the entire overground public transport (€ in the morning peak hour; our elaboration).

Rescaldina Solaro Solaro Arcore 2014 Bovisio-Masciago Desio Lissone Villasanta Vimercate Paolo Beria, Rafaele Grimaldi Cesate Va re do Cerro Maggiore Limbiate Vanzaghello Legnano Concorezzo Nova Milanese Muggiò Monza Magnago Garbagnate Milanese Senago Paderno Dugnano San Giorgio su Legnano Agrate Brianza TRASPOL - LaboratorioVilla Cortese di PoliticaCanegrate dei Trasporti DairagoPolitecnico di Milano Lainate Cinisello Balsamo Caponago Castano Primo Nerviano Brugherio Piano Urbano della Mobilità Sostenibile Cusano Milanino Carugate Parabiago Arese Bollate Buscate Busto Garolfo Cormano Arconate Bussero Pogliano Milanese Bresso Novate Milanese Sesto San Giovanni Cologno Monzese Rho Baranzate Casorezzo Cernusco sul Naviglio

Va nza go Sc.: Linee di Forza PGT Robecchetto con Induno Pregnana Milanese Vimodrone Cassina de' Pecchi Pero Cuggiono Arluno Ossona Vignate Mesero Cornaredo Pioltello Santo Stefano Ticino Sedriano Marcallo con Casone Segrate Vittuone Settimo Milanese Bernate Ticino Bareggio

Milano Rodano

Bofalora sopra Ticino Corbetta Variations in userMagenta surplus - Origin Cusago Cesano Boscone Peschiera Borromeo Pantigliate [€ during peak hour] Cisliano Corsico

more thanRobecco sul-130.0 Naviglio Cassinetta di Lugagnano -129.9 - -100.0 Albairate Trezzano sul Naviglio Mediglia -99.9 - -70.0 Buccinasco Assago -69.9 - -40.0 Gaggiano Tribiano Vermezzo

-39.9 - -10.0 Abbiategrasso

Zelo Surrigone Rozzano San Giuliano Milanese -9.9 - 10.0 Opera Colturano Gudo Visconti 10.1 - 40.0 Dresano Zibido San Giacomo 40.1 - 70.0 Ozzero Noviglio 70.1 - 100.0 Locate di Triulzi Melegnano Rosate Basiglio Morimondo 100.1 - 130.0 Pieve Emanuele Carpiano

Cerro al Lambro Lacchiarella more than +130.0 Vernate Binasco Bubbiano Calvignasco

Figure 6: Variation in consumer surplus due to the 6 new high-performance public transport lines envisaged by the PGT (€ in the morning peak hour; our elaboration). Advances in Operations Research 11

4.2. Te Rail Connection between Malpensa Terminal 2 and the them. In addition, models give the quantities, in terms of daily Simplon Line. Te project presented by the Lombard railway passengers, for every mode on each OD pair, allowing us to company (FerrovieNord S.p.A.) and the airport manager of calculate the users changing modes. Finally, model outputs, Milano Malpensa and Milano Linate (SEA S.p.A.) proposes as in the previous case, also included data used to correct the an extension of the existing rail tracks from Malpensa monetary transfers in the CBA. airport’s terminal 2 to railway station, located on Overall, the output of the regional model consists of the Simplon rail line. Te aim of this new connection is to a database fle with tables of attributes (generalised cost), increase the number of direct services, both national and quantities (amount of users), and transfers (fares, tolls, and international, stopping at the airport. Due to the relocation taxes) per 238,210 origin-destination pairs and 8 (2 × 4) of actual services on the new tracks, the project allows the mode and travel purpose combinations. By means of SQL release of capacity on the Simplon rail axis, thus enabling procedures, we estimated the surplus variation using the the regional government to increase frequencies of some RoH method. Once the core calculations were done per suburban services. Tis project was the very frst application ODpair,mode,andtravelpurpose,weproceededwiththe of the regional and national guidelines, recently issued [21, aggregation of the results in 1,455 origin and destination 22]. zones, using the same zoning of the model. Te same thing Similartowhatwaspresentedforthepreviouscase, has been done for all attributes, quantities, and transfers. for the CBA assessment, we interfaced the transport model, Te simplifed model is based on 50 origin-destination pairs developedbytheLombardyRegion,withtheevaluationpro- corresponding to the relation between Malpensa airport and cedure, developed with a database and spreadsheet sofware. the main provincial capitals (and surrounding hinterlands) In this case, the transport model was developed quite recently outside of the Lombardy Region; the fnal output referred to (it was used for the frst time in 2015 to evaluate the Regional 2(2× 1) mode and travel purpose combinations; once the Program on Mobility and Transport). For this reason, in the surplus calculation was done for each of the initial 5 transport preliminary evaluation phase, a higher efort was devoted to modes,theresultswereaggregatedintheprivateandpublic debug and calibration procedures (see below). Tese opera- mode to ensure comparability with the regional model. tions were made possible by the geographical visualizations of Afer the aggregation, the obtained data of both models surplus variation efects through the interactions with a GIS have been interfaced with spreadsheet sofware for the CBA, sofware (see Section 4.2.2). and limited to regional model data, with a GIS sofware to Given that the expected efects mainly spread at the produce cartographical representations of the main variables. regional level, model zoning, user characteristics, and trans- In total, eight fnal scenarios have been evaluated through port modes presented a higher level of aggregation in com- this procedure. However, even if this number is defnitely parison with the previous case. lower than the total scenario evaluated for the mobility plan, In detail, the transport model provided the generalised we take even more care to develop ad hoc debug procedures cost components of each origin–destination (OD) pair for within the automation process. four diferent travel purposes (work, study, leisure, and Tis efort was necessary to allow a perfect interaction business trips) and, at the frst logit stage, the transport between the RoH method and the regional transport model modes considered were private and public .Tenumberof output.Infact,whilelogitaloneallowstheintroduction passengers, for every mode on each OD pair, referred to of “out-of-scale” generalised costs for nonexisting options daily movements inside the Lombardy Region and between (typically putting 9.999 in the generalised cost components), Lombardy and Switzerland. In parallel, we developed a the RoH does not. In other words, both reference and simplifed transport model on a spreadsheet, to include it in postproject scenario have to be “feasible” for every existing the evaluation of other high-speed rail passengers originating combination of transport modes and travel purpose. Oth- from other Italian regions. For the characteristics of attracted erwise,ifthatalternativebecamefeasibleduetotheproject users, in this secondary model, we considered a unique travel implementation, the RoH method will return unrealistic user purpose (leisure) and car (as driver), car (as passenger), surplus values. coach,HStrain(plusshuttlebusinterchange),andHS Tis was initially the case of some OD pairs in the train (plus Malpensa express train interchange) as available Lombardy transport model within the public mode (the use transport modes. Tis model was calibrated using a Customer of public transport was capped to a maximum travel time Satisfaction survey on Malpensa airport users realized in 2016 of 2 hours), which were “not existing” (with a conventional for SEA S.p.A. 9.999 GC associated) before the project and “existing” (with In both models, each segment of the simulated mobility is a realistic GC associated) afer. Tis produced wrong results associated with a set of calibrated � coefcients (5), including that were pointed out thanks to the transposition of the the values of time (per trip purpose and per mode). To results on a GIS sofware (other anomalies were detected ensure results comparability, in the simplifed model, we in relation to incoherent railway station connectors and considered the same value of time for leisure purposes simulated service tarifs). included in the regional transport model. Diferently from In comparison with the SUMP case, the Appraisal Sum- the elaboration presented in the previous case study, no active mary Table has been split between fnancial and economic modes were included in these simulations. Consequently, performances. Te two analyses difer for how they treat we were able to use directly generalised costs provided by user surplus and externality components (included in the models, thus ensuring the highest level of consistency with economic CBA, but not in the fnancial one). Net Present 12 Advances in Operations Research

Value (NPV) and Internal Rate of Return (IRR) have been cal- 4.2.2. Outputs and Results. In order to make the decision culated for both parts, while the Net Beneft over Investment of the regional government more transparent and informed, Ratio (NBIR) and the Beneft Cost Ratio (B/C) are indicators the outputs of the assessment have been presented in a onlyforthelatter.Inthisstage,nobudgetconstraintis homogeneous and detailed way. Documents and analyses foreseen and all actions are included. When, at latter stages, clarify all the relevant facts that should back the decisions, the available budget will be defned, these constraints can not limited to the sole aggregate CBA indicators (NPV, be managed consistently using appropriate algorithms [41]. NBIR, B/C, and IRR). As for the previous case, results were Lastly, a separate tool for Risk Analysis was implemented presented through an Appraisal Summary Table (Figure 7) to test the critical variables identifed by the Sensitivity and a Book of Maps (Figure 8). Analysis (for each scenario, investment costs, user surplus, A particular care was taken with the scenario comparison, externalities, and demand growth trends were tested). Te in order to enrich the undergoing debate between decision- term “critical variable” refers to those components for which makers and stakeholders. Interestingly, results underline a a variation of 1% of their value leads to a percentage variation series of critical aspects, common for all scenarios, that none equal to or greater than the VANe [21, 22]. of the actors had foreseen before. First, the hypothesized network reconfguration was con- 4.2.1. Scenarios. Previous to the assessment phase, public siderably benefcial for regional users that move between actors and stakeholders defned a set of 8 scenarios difering the regional capital and its hinterland, but—unexpect- in terms of simulated demand (based on, resp., a conserva- edly—airport users were associated with a loss of surplus − − tive and optimistic growth in air passengers for the period (from 0.01 to 0.04 €/day per passenger) and with a shif 2016–2025), feasible rail projects and, consequently, diferent from public transport to private car. networks and supply. Tanks to the cartographical visualization of the phe- In particular, in order to ensure faster connections nomenon (Figure 8), it was clear how this particular result between Milan and the airport, and thus possibly attracting was a direct consequence of the new path envisaged for both new demand and shifing the existing one from airport Malpensa express service. In fact, according to regional OD shuttle buses, decision-makers hypothesized to drop one matrix data, almost 67% of users direct to and coming of the two Milan stops (Milano Porta Garibaldi) from the from the airport are generated/attracted by Milan. Tus, airport express train. ensuringafasterconnectionfromMilanoCentralestation throughcancellingtheintermediatestopofMilanoPorta Besides the main aim of ensuring a faster and more Garibaldi implicates an increase in travel time, and eventually frequent connection with the airport, another political goal inthenumberofinterchanges,forthoseuserslocatedin was to demonstrate quantitatively the necessity of redesigning the southwest and northwest of Milan. Only those located or even deleting part of a correlated rail project, named in northeast areas obtain a reduction in travel time (for “Potenziamento Rho-Gallarate e Raccordo Y.” due to poten- remaining zones, thanks to the existing metro network, the tial interferences in train circulations caused by the foreseen accessibility of these two stations are equivalent). Overall, the Y-shaped fat junction. Tis fat junction was approved by the netefectforMilaneseusersisaloss in surplus in respect to national government in 2007 and inserted into the Strategic the airport connection. Infrastructure Program (PIS). Te approval process did not Secondly, the travel time reduction of 6 minutes for HS require either an assessment or preliminary design phase passengers proved to be not sufcient to promote a sensible duetothespecialconditionallowedtotheso-called“Legge modalshifinfavourofthepublictransportmode(Figure9). Obiettivo”, abrogated in 2016 (for critical aspects related to In fact, the increase in user surplus is almost completely “Legge Obiettivo” projects see [42, 43]). related to the reduction of the number of interchanges (the On the contrary, airport managers were mainly focused ratio of �Interchange on �Cost shows that the perceived cost on enlarging the catchment area of the airport through for each interchange is equal to 50 €, suggesting that this adding,tothealreadyforecastedsuburbanandregional typology of users considers a direct service more attractive supply [44], other market oriented rail services connecting than a connection similar in respect to travel time, but that the main regional and provincial Italian capitals. impliesevenjustaninterchange).Consequently,onthoseOD Table 3 lists the scenarios that emerged from the consul- pairs where a direct bus connection already exists, few users tation phase, with their main characteristics. areattractedfromthenewHSservice. Each scenario was constructed starting from a “question,” Lastly, both R 25|P 25s1 and R 25|P 25s2 scenarios, with posed by decision-makers, which summarizes the diferent a B/C ratio, respectively, of 1.07 and 1.22, show a limited contexts in which the project could be realized or not. From a improvement in consumer conditions in respect to project methodological point of view, all those services that, entirely costs. Tus, it was not entirely possible to validate the thesis or for part of their path, generate user benefts not directly of the public decision-maker on the efectiveness of the frst connected to the project under assessment were considered solution in comparison with the latter. However, this result invariants. Likewise, only the infrastructural investments is partially misleading because, due to the preliminary stage necessary to ensure the supply remodelling envisaged were of project design, evaluations utilized feasible train timetables considered. Other projects, even if not yet realized, have been only for the new services envisaged. On the contrary, possible eventually considered as invariants between the reference and interferences with the already existing services were not postproject scenarios. considered. Advances in Operations Research 13

Table 3: Project scenarios.

∗ ∗ ∗ ∗ ∗ ∗ ∗ Scenario code R 18 P 18 R 25 P 25s1 P 25s2 P 25s0 P 30 ∗∗ ∗∗ ∗∗ ∗∗ OD matrix horizon 2015 2015 2025 2025 2025 2025 2025 Infrastructure components Rail track T2 - Gallarate xx x Yfatjunction x Ysplit-leveljunction x Fourth rail track Rho-Parabiago xx x xx Fourth rail track Parabiago- Gallarate x Forecasted rail services and frequency � � � Malpensa Express (Milan – Saronno – 30 30 60 Terminal 2) � Malpensa Express (Milano – Saronno – 30 Terminal 2 - Gallarate) � � Malpensa Express (Milano – Rho – 30 15 Gallarate – Terminal 1) � � Malpensa Express (Milano – Rho – Y 30 60 junction – Terminal 2) � � � � Regional train (Bergamo – Saronno – 60 60 60 60 Gallarate) � � � Regional train (Bergamo – Saronno – 60 60 60 Gallarate – Terminal 1) � � Suburban train S9 (Albairate – Saronno) 30 30 � � � � Suburban train S9 (Albairate – Saronno – 30 30 30 30 ) � Suburban train S9 (Albairate – Saronno – 30 Busto Arsizio – Gallarate – Terminal 1) � � � � Suburban train S15 (Milan – Parabiago) 30 30 30 30 � Suburban train S15 (Milan – Parabiago – 30 Gallarate – Terminal 1) HS train (Multiple Origins -Milan– Spot Spot Saronno – Terminal 2) HS train (Multiple Origins -Milan– Spot Spot Gallarate – Terminal 1) HS train (Multiple Origins -Milan–Rho Spot Spot – Y junction – Terminal 2) ∗ ∗∗ R stands for state of the art scenario, while P is associated to post-project scenario; in these scenarios, both conservative and optimistic demand was considered.

From this analysis, decision-makers decided to allow the Tis need is more and more actual, given the increasing shif progress of the infrastructural project to the next design of mobility planning practices [1] from a single infrastructure phase and, at the same time, to prepare further checks aimed to complex and consistent urban plans, to take advantage of at optimizing network supply. the benefts of policy packaging [2]. To reach this goal, once a transport model is available, it is convenient to extract the needed data from the chosen model 5. Conclusions and to adopt, depending on whether nonadditive policies are included in the simulation or not, either the Rule of Half or Cost-beneft analysis and public expenditure assessment logsum methods for consumer surplus calculation. techniques are broadly studied in literature. However, some Another objective of the paper deals with the enrichment relevant aspects of evaluation, especially related to the practi- of the outputs to allow a better evaluation. Tanks again to the cal application in complex cases and to the efective inclusion integration with a transport model, it is possible to provide a of CBA in the policy design process, remain unsolved. geographical and social distributive analysis, spatially depict- Te primary objective of this paper is to give indications ing the efects on consumer surplus, and of envisaged actions, about how to correctly evaluate, using Cost-Beneft Analysis, policies, and projects. Tis tool could potentially be applied complex urban mobility plans and infrastructural projects. also to spatially represent other variables (such as safety or 14 Advances in Operations Research

Figure 7: An example of Appraisal Summary Table organisation.

(a) (b)

Figure 8: Total variation in user surplus. (a) Scenario R 25|P 25s1; (b) scenario R 25|P 25s2.

environmental benefts). However, in order to carry out this improve the transparency and the awareness of the choices type of analysis, a deeper interaction with the transport model taken. is needed. In particular, information on the diferent paths In particular, through the description of two operative between OD pairs have to be collected from the fourth step case studies, we show evidence on how these two tools can of the transport model (“route assignment” phase). provide a signifcant support to decision-makers: by quan- A second possible output to efectively represent and titatively demonstrating how, in mature networks, smaller communicate the results of the evaluation is the Appraisal actions have a systematically higher efciency than large and Summary Table.Bothtools,byimprovingresultsreadability, expensive projects (SUMP case study) and by unearthing can help politicians, policy-makers, stakeholders, and citizens possible critical aspects of the envisaged network supply to correctly understand project and plan efects and in general (Malpensa airport rail connection case study). Advances in Operations Research 15

University and Research (MIUR), within the SIR programme (DDno.197del23gennaio2014).

References 400 R_18 | P_18 R_25 | P_25s0 R_25 | P_25s1 R_25 | P_25s2 R_25 | P_30 R_25+ | P_25s1+ R_25+ | P_25s2+ R_25+ | P_30+ [1] Eltis, Developing and implementing a Sustainable Urban Mobility 200 Plan. Guidelines, Prepared for the European Commission - - Directorate-General for Mobility and Transport, Brussels, Bel- −200 gium, 2013. −400 Millions € Millions [2] M. Givoni, “Addressing transport policy challenges through −600 policy-packaging,” Transportation Research Part A: Policy and −800 Practice,vol.60,pp.1–8,2014. [3] EC (2013). Together towards competitive and resource-efcient urban mobility. COM(2013) 913 fnal. Communication from Investment costs VA Ne the Commission to the European Parliament, the Council, the Revenues User beneft LR European Economic and Social Committee and the Committee Maintenance costs VA Nf of the Regions. Brussels, Belgium. Externalities User beneft HR [4] D. Banister, “Te sustainable mobility paradigm,” Transport  Running costs VANe COMPF ( = 1.15) Policy,vol.15,no.2,pp.73–80,2008. Figure 9: CBA compact indicators and costs distribution. [5] A. L. Bristow and J. Nellthorp, “Transport project appraisal in the European Union,” Transport Policy,vol.7,no.1,pp.51–60, 2000. [6] P.Bickel, R. Friedrich, A. Burgess, P.Fagiani, A. Hunt, and G. De Lastly, these tools can be also a part of a debug procedure Jong, Developing Harmonised European Approaches for Trans- of the transport model itself, thus providing hints on how to port Costing and Project Assessment (HEATCO). Deliverable D6: return more consolidated results from the simulation point Case Study Results, University of Stuttgart, 2006. of view. [7]P.Beria,M.Giove,andM.Miele,“Acomparativeanalysisof assessment approaches. Six cases from europe,” International Journal of Transport Economics,vol.39,no.2,pp.185–217,2012. Additional Points [8]P.Beria,I.Maltese,andI.Mariotti,“MulticriteriaversusCost Beneft Analysis: A comparative perspective in the assessment Highlights. (i) Traditional CBA can also be applied to the of sustainable mobility,” European Transport Research Review, evaluation of complex transport plans. (ii) We revised the vol. 4, no. 3, pp. 137–152, 2012. ways to calculate consumer surplus: generalised costs com- [9] D. Tsamboulas, G. S. Yiotis, and K. D. Panou, “Use of multicri- parison, Rule of Half, and logsum. (iii) We comment on teria methods for assessment of transport projects,” Journal of advantages and limits of both methods, suggesting when Transportation Engineering,vol.125,no.5,pp.407–414,1999. logsum has to be preferred to the Rule of Half. (iv) We [10] G. Marsden and C. Snell, “Te role of indicators, targets showhowCBAcanbeintegratedwithtransportmodels.(v) and monitoring in decision-support for transport,” European Interaction with decision-makers can be improved by using Journal of Transport and Infrastructure Research,vol.9,no.3, spatial distributive analysis. pp.219–236,2009. Te attribution of the diferent sections is the following: [11] A. Tudela, N. Akiki, and R. Cisternas, “Comparing the output of Sections 1, 2, 3, and 4.1 have been written by Paolo Beria cost beneft and multi-criteria analysis: An application to urban transport investment,” Transportation Research Part A: Policy and Rafaele Grimaldi and were originally included in the and Practice, vol. 40, no. 5, pp. 414–423, 2006. working paper Beria & Grimaldi [23]. Alberto Bertolin is also [12] T. Sager, “Te comprehensiveness dilemma of cost-beneft the author of the remaining sections. analysis,” European Journal of Transport and Infrastructure Research,vol.13,no.3,pp.169–183,2013. Conflicts of Interest [13] S. Damart and B. Roy, “Te uses of cost-beneft analysis in public transportation decision-making in France,” Transport Te authors declare that there are no conficts of interest Policy,vol.16,no.4,pp.200–212,2009. regarding the publication of this paper. Since September [14] A.L.Bristow,P.J.Mackie,J.Nellthorp,andG.D.Jansen,“Costs, 2017, Rafaele Grimaldi has been employed at Autoritadi` prices and values in the appraisal of transport projectsEuropean Regolazione dei Trasporti (the Italian transport regulation principles and practice,” in Proceedings of the Eighth World authority), but this article presents the results of former Conference in Transport Research, Antwerp, Belgium, 1998. research and does not represent the views of the authority. [15]J.Nellthorp,S.Grant-Muller,H.Chenetal.,“Comparingthe economic performance and environmental impact of Trans- European Road Networks: the EUNET assessment tool,” in Acknowledgments Proceedings of the Second European Road Research Conference, Brussels, Belgium, June 1999. Te research is part of the project “QUAINT” (protocol: [16] D. G. Regio, Guide to Cost-Beneft Analysis of investment RBSI14JR1Z),supportedbytheItalianMinistryofEducation projects.StructuralFunds,CohesionFundandInstrumentfor 16 Advances in Operations Research

Pre-Accession, Directorate General Regional Policy. European [35] AMAT, Piano Urbano della MobilitaSostenibile(PUMS)` ,Agen- Commission, 2008. zia Mobilita` Ambiente e Territorio, Milano, Italy, 2015. [17] EC-EIB, RAILPAG: Railway Project Appraisal Guidelines,Euro- [36] AMAT, Piano Urbano della MobilitaSostenibile(PUMS)–` pean Commission – European Investment Bank, 2004. Rapporto ambientale, Agenzia Mobilita` Ambiente e Territorio, [18] D. Browne and L. Ryan, “Comparative analysis of evaluation Milano,Italy,2016. techniques for transport policies,” Environmental Impact Assess- [37] DfT, Transport Analysis Guidance (TAG). An Overview of ment Review,vol.31,no.3,pp.226–233,2011. Transport Appraisal, Department for Transport, UK, 2014. [19] S. Mafi and R. Parolin, “Estimating benefts for modal shifers: [38] PWC, “Evaluation of the costs and benefts to the community of a methodological remark,” in Selected Proceedings of the 13rd fnancial investment in cycling programs and projects in New World Conference on Transport Research,2013. SouthWales,”FinalReport.Preparedfor:RoadsandTrafc [20] R. Grimaldi and P. Beria, “Open issues in the practice of cost Authority of NSW and the Department of Environment and beneft analysis of transport projects,” in Proceedings of the 13rd Climate Change, Australia, 2009. World Conference on Transport Research,2013. [39] TemaNORD, CBA of Cycling, Nordic Council of Ministers, [21] MIT, Linee Guida per la valutazione degli investimenti in Copenhagen, Denmark, 2005. opere pubbliche nei settori di competenza del Ministero delle [40] DfT, NATA Refresh: Appraisal for a Sustainable Transport Infrastrutture e dei Trasporti ai sensi del D. Lgs. 228/2011. System, Department for Transport, UK, 2009. Ministero delle Infrastrutture e dei Trasporti - Direzione Gen- [41] A. Bonnafous and P. Jensen, “Ranking transport projects by erale per lo sviluppo del territorio, la programmazione ed i their socioeconomic value or fnancial internal rate of return?” progetti internazionali e Nucleo di Valutazione e Verifca degli Transport Policy,vol.12,no.2,pp.131–136,2005. Investimenti Pubblici (NVVIP). 2016. [42] SIPoTra, “Quale futuro per la politica dei trasporti dopo il [22] Regione Lombardia, Linee Guida per la redazione di Studi di nuovo codice degli appalti,” I quaderni di SIPoTra 1/2017, 2017. Fattibilita`, Interventi Infrastrutturali, Milano, Italy, 2015. [43] C. Virno, Se alle grandi opere mancano le fondamenta. Della val- [23] P. Beria and R. Grimaldi, “Cost Beneft Analysis to assess urban utazione, 2005, http://www.lavoce.info/archives/22976/se-alle- mobility plans. Consumers’ surplus calculation and integration grandi-opere-mancano-le-fondamenta-della-valutazione/. with transport models,” Working Paper,2014. [44] Regione Lombardia, “Programma Regionale MobilitaeTrasp-` [24] J. E. Stiglitz, Economics of the Public Sector,W.W.Norton& orti (PRMT),” Struttura Programma Regionale della Mobilitae` Company, 3rd edition, 2000. dei Trasporti – DG Infrastrutture e Mobilita,` Milano, Italy, 2016. [25] E. Cascetta, Teoria e Metodi della Ingegneria Dei Sistemi Di Trasporto, Torino, Italy, 1998. [26] J. Ortuzar´ and L. G. Willumsen, Modelling Transport,John Wiley & Sons, Chichester, UK, 1990. [27] E. Cascetta, Modelli per i Sistemi di Trasporto: Teoria e Appli- cazioni,UTET,Torino,Italy,2006. [28]G.DeJong,M.Pieters,A.Daly,I.Graafand,E.Kroes,and C. Koopmans, Using the Logsum as an Evaluation Measure. Literature and Case Study,RANDEuropeWorkingPaper. Prepared for AVV Transport Research Centre, Leiden, Te Netherlands, 2005. [29] G. de Jong, A. Daly, M. Pieters, and T. van der Hoorn, “Te logsumasanevaluationmeasure:Reviewoftheliterature and new results,” Transportation Research Part A: Policy and Practice, vol. 41, no. 9, pp. 874–889, 2007. [30] P. Brunton, Transport User Benefts: An Alternative to the Rule of Half,AECOM,2012. [31] J. Bates, “Economic evaluation and transport modelling: theory and practice,” in Moving through Nets: Te Physical and Social Dimensions of Travel, pp. 279–351, 2006. [32] S. Mafi, R. Parolin, M. Brambilla, and R. Scatamacchia, TRACECA Appraisal Manual. Guidelines for Pre-Feasibility of Transport Projects with Exercises and Case Studies. A project implemented by TRT Trasporti e Territorio in association with Alfen Consult, Dornier Consulting and PTV,for the TRACECA IDEA project. 2012. [33] K. Geurs, B. Zondag, G. de Jong, and M. de Bok, “Accessibility appraisal of land-use/transport policy strategies: More than just adding up travel-time savings,” Transportation Research Part D: Transport and Environment,vol.15,no.7,pp.382–393,2010. [34] J. Castiglione, J. Freedman, and W. Davidson, Application of a Tour-Based Microsimulation Model to a Major Transit Investment, San Francisco County Transportation Authority and PB Consult, San Francisco, Calif, USA, 2003. Advances in Advances in Journal of The Scientifc Journal of Operations Research Decision Sciences Applied Mathematics World Journal Probability and Statistics Hindawi Hindawi Hindawi Hindawi Publishing Corporation Hindawi www.hindawi.com Volume 2018 www.hindawi.com Volume 2018 www.hindawi.com Volume 2018 http://www.hindawi.comwww.hindawi.com Volume 20182013 www.hindawi.com Volume 2018

International Journal of Mathematics and Mathematical Sciences

Journal of Optimization Hindawi Hindawi www.hindawi.com Volume 2018 www.hindawi.com Volume 2018

Submit your manuscripts at www.hindawi.com

International Journal of Engineering International Journal of Mathematics Analysis Hindawi Hindawi www.hindawi.com Volume 2018 www.hindawi.com Volume 2018

Journal of Advances in Mathematical Problems International Journal of Discrete Dynamics in Complex Analysis Numerical Analysis in Engineering Dierential Equations Nature and Society Hindawi Hindawi Hindawi Hindawi Hindawi www.hindawi.com Volume 2018 www.hindawi.com Volume 2018 www.hindawi.com Volume 2018 www.hindawi.com Volume 2018 www.hindawi.com Volume 2018

International Journal of Journal of Journal of Abstract and Advances in Stochastic Analysis Mathematics Function Spaces Applied Analysis Mathematical Physics Hindawi Hindawi Hindawi Hindawi Hindawi www.hindawi.com Volume 2018 www.hindawi.com Volume 2018 www.hindawi.com Volume 2018 www.hindawi.com Volume 2018 www.hindawi.com Volume 2018