One of the major critiques of land use-transport interaction (LUTI) models over the ages has been their over-dependence on individualized software and context. In an effort to address some of these ...concerns, this study proposes a framework to construct “virtual cities” that can act as sandboxes for testing different features of a LUTI model, as well as provide the capability to compare different LUTI models. We develop an approach to translate any prototypical transportation infrastructure network into a plausible land use zoning plan and synthetic population that are suitable for spatially detailed LUTI microsimulation of the virtual city. Disaggregate units of spatial geometry, like parcels and postcodes, are generated using geospatial techniques applied to the transportation network. Households and jobs are randomly sampled from an actual city, and allocated in the virtual city based on matching density gradients. Students are matched with schools and workers are matched with jobs to complete the calibration of a synthetic population for the virtual city. Following the adjustment of behavioral models to complement the reduced scale of the virtual city, we demonstrate the integration between the land use and transportation simulation components in our LUTI model, SimMobility. The benefits of faster convergence times and shorter simulation times are clearly demonstrated through this exercise. We hope that this study, and the open-source releases of the SimMobility software with the virtual city database, can accelerate experimentation with LUTI models and aid the transition from individualized LUTI models to a common shared integrated urban modeling platform.
This paper stresses the lack of attention paid to the geographical definitions of cities in LUTI models as one key detrimental aspect to transferring and generalising LUTI results. First, the ...argumentation develops from a meta-analysis of peer-reviewed publications about LUTI applications in European cities. We show that most authors do not assess findings against potential geographical biases. Second, theoretical simulations are conducted with UrbanSim applied to a synthetic urban area. By varying the geographical limits of the system and population endowments, our simulations confirm that the absence of control on city delineation weakens the results. Finally, the paper suggests methodological guidelines to improve the comparability of LUTI applications and push forward their theoretical agenda.
In recent years the interest in urban mobility has grown considerably, not only due to the local increase in negative externalities generated by transport, but also because recent technological ...innovations are offering effective solutions especially in urban context. In particular, the introduction of Connected and Automated Vehicles (CAVs) could radically change the mobility scenario allowing, on the one hand, a widespread diffusion of shared vehicles that could feed the stations of the mass rapid transit network, improving the attractiveness of Public Transportation (PT), and on the other, the implementation of Travel Demand Management (TDM) measures on large areas of the most densely urbanized (and congested) territory of a city, without reducing accessibility and creating social exclusion. The present study aims at evaluating, through a system of Land-Use Transportation Interaction (LUTI) models, the impacts on transport demand and on population and activities location, of transportation policies oriented to both enhancing PT and restricting the individual use of the car. The case study analyzed is represented by the urban area of Rome. Several scenarios have been simulated and compared by means of sustainability indicators. Preliminary results show that the improvement of PT services, combined with the introduction of car use restriction and car free areas, do induce not only a significant modal shift towards more sustainable transportation modes, but also a limitation of urban sprawl.
This paper presents an integrated and strategic model to simulate the dynamic interaction processes between land-use and transport at an aggregate level in Bogotá region. The model uses Causal Loop ...Diagrams from Systems Dynamics to explain cause and effect relations and incorporates a calibration for the base-year. This model is inspired by the basic hypothesis of the MARS model, although due to the particular characteristics of the study area, it was necessary to make changes. In cities like Bogotá, there is a lack of understanding of the importance of land-use and transport integration challenges, a focus mainly on the short term, a limited knowledge about quantification of the impact of integrated policies, and uneven information availability. Data limitation has been identified as a significant limitation. Consequently, innovative approaches are required in developing cities to adapt to situations where limited information is available. This paper describes the basis, capabilities, and potential uses of LUTI-Bogotá model.
Economics, demographics, land use change, and transport interact in complex and dynamic ways. To inform urban policy decision-making it is important to develop tools that incorporate the interactions ...of these systems in meaningful ways. Historically, models of these systems have been developed in isolation, and many agencies have already invested large amounts of time and money into developing these independent models. It is thus often desirable to couple existing models, rather than to develop a completely new integrated model. Coupling together independently developed models introduces many challenges including dealing with different spatial and temporal scales, base datasets and levels of aggregation, as well as bringing up deeper questions around the underlying paradigms, assumptions and limitations of the models. This paper describes the key challenges encountered when coupling an existing integrated model of land use change, economic activity, and population (the ‘Integrated Scenario Explorer’ model) with an existing transport model (the ‘Wellington Transport Strategy Model’) for the Wellington region in New Zealand. The case study results show that the coupling produces substantial differences in the urban land use change looking forward to 2041, specifically it affects the location of the urban intensification. The paper summarises the important considerations for modellers when coupling independently developed models, highlights the importance of understanding the underlying theories of the component models, and emphasises the need to develop pragmatic solutions that are guided by the intended use of the resulting integrated model.
•Two existing models, one of transport and one of land use change, economics, and population, are coupled together•Key challenges encountered by modellers when coupling independently developed models are summarised•The implementation of the loose coupling for the Wellington region in New Zealand demonstrates pragmatic solutions•Loose coupling with a transport model significantly affects the location of urban expansion, even with long timesteps
Robust calibration and validation of applied urban models are prerequisites for their successful, policy-cogent use. This is particularly important today when expert assessment is questioned and ...closely scrutinized. This paper proposes a new model calibration-validation strategy based on a spatial equilibrium model that incorporates multiple time horizons, such that the predictive capabilities of the model can be empirically tested. The model is implemented for the Greater Beijing city region and the model validation strategy is demonstrated over the Census years 2000 to 2010. Through forward/backward forecasting, the model validation helps to verify the stability of the model parameters as well as the predictive capabilities of the recursive equilibrium framework. The proposed modelling strategy sets a new standard for verifying and validating recursive equilibrium models. We also consider the wider implications of the approach.
In this paper we present an activities–location choice model with endogenous price which simulates, based on Expected Random Utility principle, the behaviour of several agents of the urban system ...(e.g. the workers distinguished by income, the firms by economic sector) to estimate the spatial distribution of socio-economic activities within the study area as well as the impact of differential changes in accessibility on the dwelling price. The study area for this research is the metropolitan area of Napoli (South Italy), for which we show the results of the model estimation and the results of a “backcasting” analysis.
The development of integrated techniques to evaluate long-term urban trends is a top priority in terms of creating a more sustainable society. In order to take a step forward from traditional ...peak-hour models, the purpose of this paper is to develop a travel demand (generation and attraction) strategic model of a typical day. The methodology integrates a commuting and non-commuting-related tour generation/attraction model and a Land-Use and Transport Interaction (LUTI) model to capture the feedback mechanisms that may affect tour generation in the long term.
The travel demand model is developed from a cross-sectional household mobility survey carried out in Bogota in 2011. Multiple linear regression analysis is used to investigate and model the effect of income, household size and structure, car ownership, travel time and mixed land-use on the number of trips generated by a household on an average weekday. The trip attraction models are at best estimated using zonal data. The Bogota LUTI model that is adopted in this methodology has been benchmarked against other published models to compare its features and capabilities. The integration of the travel demand model and Bogota LUTI model will allow for a discussion on the suitability of the proposed modeling approach in order to test several scenarios with high motorization growth rates, and the possible advantages (or disadvantages) associated with them; thus, providing useful knowledge that will inspire future research on the evaluation of complex transportation policies in developing cities.
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