Accessibility-based land use and transport interaction (LUTI) models are tools for policy assessments that facilitate coherent implementation of sustainable strategic urban plans. This study aims to ...improve one of those LUTI models introducing the different impact of factors influencing residential and workplace choice by computing local coefficients. In particular, this research explores the methodology of integrating the public choice model into the MARS (Metropolitan Activity Relocation Simulator) model using a complex accessibility indicator. We established a new approach to input the variation of the influence of each public service across space with the use of Geographically Weighted Regression (GWR). The model update and extension of MARS are all based on the Region of Madrid, Spain. Using the new accessibility indicator yielded better results and corrected some under estimation and overestimations in the number of workplaces. The correlation using the new accessibility indicator is significantly higher than the one using the old one. The prediction using the new indicator achieves better results for the whole area whatever the zone is small or large. The analysis evidences the convenience of GIS and LUTI combination to improve model accuracy and precision. Using the new accessibility indicator based on local coefficients, MARS model fits better with the real data in respect of the distribution of workplaces and residents, which are the key representatives of the land use sub-model.
•Developing an up-to-date accessibility measure considering both the job accessibility and the accessibility to public services.•Adopting Geographically Weighted Regression to estimate local coefficient for generating the new accessibility indicator.•Improving the accessibility-based LUTI model MARS through the complex accessibility indicator.•A good practice of combining the knowledge of geographers and transport planners.
In the Computable Urban Economic (CUE) Model, one land-use transport interaction (LUTI) model, improving the accuracy of the Location Choice Model is important to evaluate the effects of introducing ...urban transportation policies. However, our previous study revealed that the substantiation of the indirect utility function by a linear expenditure system has not been verified and that location choice behaviors estimated using the logit model depends on the adjustment factor. Therefore, in this study, we first examined the logical meaning of the utility function by a linear expenditure system, and then focused on identifying major constituent factors of the adjustment factor and statistically verified the adjustment factor and urban amenities. As a result, we have identified the following facts: that the conventional indirect utility function may underestimate the effect of introducing urban transportation policies; that if effects are estimated using WLS after adding housing supply factors to the indirect utility function, the estimation accuracy will be improved; and that the major constituent factors of the adjustment factor are those expressing local characteristics of cities and wards.
Land-Use and transport interaction models today take an important role as decision-making tools, especially in a context marked by the reinforcement of economical, energy and environmental ...constraints. If the estimation of transport demand and accessibilities in these models depends on densities, these densities are often viewed as exogenous. This paper intends to render them endogenous by measuring the effect of accessibilities on intra-urban densities in the urban area of Lyon in 1990, 1999 and 2006, and defining an evolution law over time for the coefficients of the model. The successive relax of the hypothesis of spatial homogeneity and monocentrism which characterize the Bussière model and the improvement of the transport cost measure (distance from the center of the urban area, generalized time, gravity accessibility to jobs) give good static results but do not allow to predict the evolutions of the population densities at the district level. The selective movements of peri-urbanization and return to the center that were stressed during this short time are far from being explained by the evolution of accessibility to the center or to jobs in the urban area. The distribution of densities in this monocentric city depends not only on the accessibility to jobs but also appear to be structured by the centrality and the distribution of the social and spatial amenities, which in part result from the urban policy and the macro-agents’ decisions.
•We propose an integrated framework to create spatially detailed and heterogeneous synthetic populations.•Households and individuals are synthesized using multiple Bayesian Networks and Generalized ...Raking.•Spatial entities in the built environment are constructed via an ontology-based data-fusion approach.•Our framework outperforms traditional population synthesis methods in our Singapore case study.•Results show heterogeneous synthetic population with detailed and rich socio-spatial information.
Agent-based models (ABMs) of urban systems have grown in popularity and complexity due to the widespread availability of high-performance computing resources and large data storage capabilities. Credible synthetic populations are crucial for the application of ABMs to understand urban phenomena. Although several (agent) population synthesis methods have been suggested over the years, the spatial dimension of synthetic populations has not received as much attention. This study addresses this myopic treatment of synthetic populations by creating two distinct components – agents and the built environment – that are integrated to form a ‘full’ spatially-detailed synthetic population. To generate agents, we used multiple Bayesian Networks (BN) to probabilistically draw pools from the microsample, followed by a Generalized Raking (GR) adjustment to match marginal controls. Using various measures, we demonstrate that our BN+GR framework outperforms more commonly used synthesis methods in both capturing the heterogeneity in the microsample and matching marginal controls. We also highlight the importance of accounting for heterogeneity by using separate type-specific models based on an explicitly defined household typology. For built environment synthesis, we generated various spatial entities such as buildings, housing units, establishments, and jobs at distinct spatial locations by fusing data from various spatial datasets. Their spatial distributions are found to effectively approximate the ‘real’ built environment in our study area. Our proposed framework can be used to generate a ‘full’ synthetic population for use in ABMs with more spatio-demographic heterogeneity than can otherwise be estimated using traditional methods.
Les modèles d’interaction transport-usage du sol prennent aujourd’hui une place importante en tant qu’outils d’aide à la décision dans un contexte marqué par le renforcement des contraintes ...économiques, énergétiques et environnementales. Si l’estimation de la demande de transport et des accessibilités dans ces modèles repose sur les densités, ces dernières sont souvent considérées comme étant exogènes. L’objectif de cet article est de tester la possibilité de les rendre endogènes en mesurant l’effet des accessibilités sur ces densités intra-urbaines de population dans l’aire urbaine de Lyon en 1990, 1999 et 2006 et de définir une loi d’évolution dans le temps des coefficients du modèle. Le relâchement successif des hypothèses d’homogénéité spatiale et du monocentrisme inhérentes au modèle de Bussière et l’amélioration de la mesure du coût de transport (distance au centre, temps généralisé d’accès au centre, accessibilité gravitaire aux emplois) donne des résultats satisfaisants en statique, mais ne permet pas de prédire les évolutions des densités de population à l’échelle des quartiers. Les mouvements sélectifs de périurbanisation et de retour au centre qui ont marqué cette courte période sont loin d’être expliqués par l’évolution des seules accessibilités au centre ou à l’emploi de l’aire urbaine. La répartition des densités dans cette ville monocentrique dépasse largement l’accessibilité aux seuls emplois. Elle semble structurée par la centralité et la distribution des aménités sociales et spatiales qui sont en partie l’œuvre des politiques urbaines et des macro-agents.
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