Métropolisation, formes urbaines et mobilité. Présentation du dossier

International audienceLa croissance de la mobilité se focalise principalement sur deux types d'espaces que sont les grands corridors européens et les métropoles, pour la plupart noeuds de ces corridors. La mobilité constitue ainsi un enjeu essentiel pour le devenir même des métropoles et plus généralement des grandes villes. Dans ce contexte, la compréhension des interaction entre la forme des localisations (population et activités), l'organisation des réseaux de transport et les comportements de déplacement suscite à juste titre un intérêt jamais démenti depuis deux décennies. (extrait de l'introduction)

Métropolisation, formes urbaines et mobilité. Présentation du dossier

La croissance de la mobilité se focalise principalement sur deux types d'espaces que sont les grands corridors européens et les métropoles, pour la plupart noeuds de ces corridors. La mobilité constitue ainsi un enjeu essentiel pour le devenir même des métropoles et plus généralement des grandes villes. Dans ce contexte, la compréhension des interaction entre la forme des localisations (population et activités), l'organisation des réseaux de transport et les comportements de déplacement suscite à juste titre un intérêt jamais démenti depuis deux décennies. (extrait de l'introduction).Métropolisation ; formes urbaines ; mobilité

Projection of the daily travel of an ageing population: The Paris and Montreal case, 1975-2020

International audienceAgeing of the population, urban sprawl and car dependency will change travel patterns. The main objective of this paper is to give elements for a better understanding of the impact of changing demographics on the long term evolution of daily mobility using demographic-based models to forecast, for the elderly population, car-ownership, trip frequency, distance traveled, average trip distance. A second objective is to measure the impact of the long term tendencies observed on the appearance of new needs of travel demand such as a rapid increase of demand-responsive transport. The paper compares two agglomerations, both in a strong ageing process, but in quite different sociocultural contexts: a large European metropolis: Paris, and a medium sized north-american city: Montreal. Many common conclusions derived from the two different cases studies reinforce the possibility of generalizing the conclusions to other situations

Long term dynamics of inequalities between French households concerning automobile

International audienceFor each quartile of income per household or per consumption unit, annual time-series have been estimated from panel surveys, with annual waves of observations from 1974 to 2007: INSEE2 Households' "Conjoncture" survey from 1974 to 1994 ; panel "Parc-Auto"3 Sofres4 since mid-80's. In these data sources, household behaviour is described through ; car ownership (percentage of households with at least one car, of which percentage of multi-car households, average number of cars per adult over 18, which is the minimum age for driving license in France) ; car use (annual mileage per household or per car). The repeated sample structure of data has been used for improving the accuracy of time-series of variables highly correlated for subsequent years [Cochran, 1977]. In mid-70's, car ownership and use were quite low for the poorest income quartile, but the difference has much decreased with all the three higher income groups, which are more homogeneous. Thus, multi-car ownership, which is mainly structured by geographic and demographic determinants, has slowed down -but not reversed- the social diffusion of automobile. As the curves representing car ownership (number of cars per adult) and car use (annual mileage per household) seem to become quite horizontal during the most recent period, logistic curves have been estimated according to time, then to real income. For each quartile of the distribution of households by income per consumption unit, saturation thresholds are estimated, as well as the date or the point of inflection. Follows a discussion on the legitimacy of pooling the data. The relationship between temporal elasticities (for each quartile) and cross-sectional income elasticities, which can be considered as a measurement of inequality at each point in time, will be discussed [Gardes and Madre, 2005]

MEASURING UNCERTAINTY IN LONG-TERM TRAVEL DEMAND FORECASTING FROM DEMOGRAPHIC MODELLING

Uncertainty on traffic forecasts may have an impact on reimbursement scheduling for investment, as well as for scenarios for operating costs. Even the best projections are based on models and assumptions, thus raising the question of their accuracy. Indeed, long term investments are risky and it is important to cope with uncertainty. This paper deals with the uncertainty on a long term projection with an Age-Cohort approach. The authors used the jackknife technique to estimate confidence intervals and observe that the demographic approach outlines the structural determinants for long term trends of mobility. Document type: Articl

L’analyse en termes de finances publiques des effets redistributifs de la politique des transports : impasse, étape ou point de départ ?

Réponse au commentaire de A. Viane

Diffusion du diesel et croissance de la circulation

Since the mid-1980s there has been a rapid to diesel-engine cars and a significant increase in road traffic in France. Are these two phenomena related?- detailed data show that a diesel vehicle replacing a petrol one has a higher annual mileage (and a petrol vehicle replacing a diesel one has a lower mileage), but that the total mileage of the household remains almost constant;- the distribution of total annual mileage for both diesel and for petrol vehicles has remained almost unchanged since 1985.Therefore, the growth in the proportion of diesel vehicles is the principal explanatory — most of the behavourial factors have remained stable.Depuis le milieu des années 80 en France, on constate simultanément une diésélisation rapide du parc automobile et une croissance importante de la circulation. Ces deux phénomènes sont-ils liés ?- sur données individuelles, on observe qu'un diesel remplaçant une voiture à essence roule davantage (et réciproquement), mais le kilométrage total du ménage varie peu ;- les distributions de kilométrage pour le diesel et pour l'essence restent à peu près constantes au cours du temps.Le principal facteur d'évolution est donc la progression de la part des véhicules diesel dans le parc ; la plupart des structures de comportement restent stables

Les marchés de l'automobile : variations du neuf et de l'occasion

From the automobile market analysis between 1973-1987, it appears that the part of new cars decreases compared with used cars, on account of increasing time ownership and propensity to take second-hand cars.Buyer’s caracteristics (more than one car owning, household income. age) have great effects on the market trend.Long run, the part of new cars should decline, but more slowly, with population ageing and purchasers decreasing (for first or second car, generally second-hand car). However, the generalization of vehicles technic control should much change the car market equilibrium.L'analyse du marché de l'automobile de 1973 à 1987 montre que la part du neuf tend à diminuer par rapport à l'occasion, avec l'allongement des durées de possession des véhicules et la tendance au remplacement par l'occasion.Les caractéristiques des acheteurs (multi-motorisation, situation financière des ménages, âge) influent beaucoup sur l'évolution des marchés.À long terme, la baisse de la part du neuf devrait continuer, mais à un rythme ralenti en raison du vieillissement de la population et de la baisse de la proportion d'accédants (passage à la seconde voiture ou accès à la motorisation, généralement par l'occasion). Toutefois, la généralisation du contrôle technique des véhicules pourrait beaucoup modifier l'équilibre de ces marchés