14 research outputs found
Modeling spatio-temporal diffusion of carsharing membership in Québec City
Abstract
During the last few years, car sharing has undergone significant growth, both in Canada and around the world. In this type of service, users share access to a fleet of vehicles, thereby giving them most of the advantages of automobile use, such as its temporal and spatial flexibility, without many of the constraints of ownership. This study analyzes the geographical and socio-economic factors that favour membership of a carsharing service in Québec City. We combined Cervero’s and Kockelman’s 5D model (density, diversity, design, distance to transit, and destination accessibility) with Hägerstrand’s concept of innovation diffusion so as to analyze the evolution of potential car-sharing membership. Zero-inflated negative binomial (ZINB) regression was used to model the spatial diffusion of the number of car-sharing members in Québec City from 1996 (two years after its inauguration) to 2008 at the local scale, with an annual time step. Results indicate that the carsharing distribution did, indeed, follow Hägerstrand’s innovation diffusion model and that, even though some of the 5D model significantly influenced membership, it was socio-economic factors (education, non-motorization, and family structure) that most greatly affected the membership rate in the service area. The model is used to assess and discuss market coverage potential in Québec City. Keywords: carsharing, sustainable mobility, Hägerstrand’s innovation diffusion model, 5D model, spatiotemporal modelin
Impacts de la restructuration du réseau d’autobus de la ville de Québec sur l’accessibilité aux emplois des femmes et sur leur mobilité professionnelle
Le réseau d’autobus de la ville de Québec a subi une importante restructuration en 1992 avec la création du Métrobus et l’ajout de lignes express. L’objectif de cet article est de vérifier si la restructuration de ce réseau a permis d’améliorer l’accessibilité aux emplois des résidentes et de favoriser leur mobilité professionnelle. Les données des enquêtes origine-destination de 1991 et 2001 réalisées par le ministère des Transports du Québec et le Réseau de transport de la Capitale sont mises à profit. Les variations spatiales et temporelles des différents indicateurs montrent une diminution sensible des durées de déplacement et une amélioration de l’accessibilité aux emplois à partir de certains secteurs de la ville et ce, en dépit d’une diminution de la part modale de l’autobus, même dans les couloirs du Métrobus. Par ailleurs, la mobilité professionnelle des femmes semble avoir progressé dans plusieurs secteurs desservis par le Métrobus.When the Quebec City public transport system was reorganized in 1992, two specific transit services were set up: the “express” and the “Métrobus.” The aim of the paper is to determine whether the reorganization of this system improved employment accessibility for residents, especially women, and supported their professional mobility by making them progress on the labour market. We used data from 1991 and 2001 OD surveys. Spatial and temporal variations of various indicators show a reduction in travel time to work and an improvement in employment accessibility, but only for certain sectors of the city, and this in spite of a reduction in bus modal split between 1991 and 2001, even in the Métrobus corridors. In addition, women’s profes- sional mobility has progressed in several sectors served by the Métrobus even when general professional progression is taken into account
L’évolution de la mobilité des femmes à Québec entre 1977 et 1996
D'importants changements sociaux et économiques ont transformé les agglomérations canadiennes au cours des vingt dernières années et ont affecté les comportements de déplacements de leurs résidant(e)s. Cet article décrit l'évolution de la mobilité des femmes demeurant dans l'agglomération urbaine de Québec durant cette période de changements. Les données sur la mobilité sont issues des grandes enquêtes Origine-Destination réalisées par la STCUQ en 1977 et en 1996. La durée et la longueur des déplacements sont obtenues par modélisation dans un système d'information géographique (SIG) en transport. Les résultats montrent que les femmes ont davantage accès à l'automobile, qu'elles se déplacent plus fréquemment, qu'elles parcourent de plus grandes distances pour se rendre au travail et que la durée de leurs déplacements-travail a diminué entre 1977 et 1996. Toutefois, en 1996, les femmes parcourent encore de plus courtes distances que les hommes pour se rendre au travail, particulièrement lorsqu'elles résident en banlieue. Elles se déplacent moins fréquemment que les hommes et ces derniers demeurent les principaux utilisateurs du véhicule familial.Canadian cities have seen important socio-economic changes in the last twenty years. These changes have also transformed the inhabitants' daily travels. The aim of this paper is to describe the mobility changes of women living in the Québec urban area during this period. We used an extensive data base from two origin-destination surveys produced by the STCUQ in 1977 and 1996. Travel distances and travel times are simulated using GIS-transportation software. Our results show that women have better access to cars, that they move more frequently, that their work trips are longer and their travel times are shorter in 1996 than in 1977. Notwithstanding these improvements, 1996 work travel of women is still shorter than that of men, especially if they are living in the suburbs. Also, they travel less frequently than men, who still are the principal users of family car
Homeworking, telecommuting and journey to workplaces - Are differences among genders and professions varying over space?
The aim of this paper is to assess differences on homeworking and teleworking behaviour among genders considering age groups, professional statuses, household structures and car access. The analysis is based on a sample of more than 30,000 workers responding to the 2001 origin-destination (O-D) survey data in Quebec City (Canada). Moreover, this paper puts specific emphasis on linking those differences in behaviour to the location of workplaces related to living places of the respondents. During the O-D survey, every worker was asked to disclose the frequency of homeworking and teleworking he/she was experiencing during the preceding weeks. Answers were later aggregated into six categories: never working at home (88.4% of respondents), working at home 1 day per two weeks or less (4.8%), 1 day per week (1.7%), 2 or 3 days per week (1.2%), 4 days or more per week (0.7%), always working at home (3.2% – homeworkers). However, those patterns show significant differences among genders (higher proportion of females are working entirely at home; higher proportion of males are occasionally working at home), age groups (younger workers seldom work at home and the proportion of teleworker increases with age – about 16% among the 55-64 years old and 27% among the elderly) and professional status (proportion of teleworkers is strongly related to qualifications and decisional status of the person, yielding higher levels of teleworking for managers, self-employed persons, professors and lawyers than for office clerks, technicians and non-qualified workers). This last relationship is very strong suggesting that job empowerment (especially ability to control time schedule) is of paramount importance for the development of teleworking. However, having higher family constraints, lone parents are seeking more flexibility on their work agenda: 12% are experiencing some level of teleworking on top of 3% of them which are homeworkers. Again, the difference appears more significant among male than among female workers, suggesting again a better control of the first group on their work schedule. Moreover, owning a driver license or holding a bus pass does not have the expected effect on teleworking: car drivers are working at home more frequently than other people; conversely 92% of bus users are going to their work place every weekday, leaving a mere 8% to teleworking and homeworking. Significant differences appear when considering workplaces and home locations within the city. People working near the city centre are more willing than others to consider teleworking, people living in the suburban areas show higher levels of homeworking. Finally, significant differences of travel time from home to work were found among various categories of teleworkers and homeworkers. Preliminary results suggest that the development of teleworking could be highly rooted to labour market and household structures as well as to the urban form. Urban sprawl is probably impeding development of teleworking, at least for Quebec City.
Comparative analysis of different survey methods for monitoring fish assemblages in coastal habitats
Coastal ecosystems are among the most productive yet increasingly threatened marine
ecosystems worldwide. Particularly vegetated habitats, such as eelgrass (Zostera marina)
beds, play important roles in providing key spawning, nursery and foraging habitats
for a wide range of fauna. To properly assess changes in coastal ecosystems and
manage these critical habitats, it is essential to develop sound monitoring programs
for foundation species and associated assemblages. Several survey methods exist, thus
understanding how different methods perform is important for survey selection. We
compared two common methods for surveying macrofaunal assemblages: beach seine
netting and underwater visual census (UVC). We also tested whether assemblages in
shallow nearshore habitats commonly sampled by beach seines are similar to those of
nearby eelgrass beds often sampled by UVC. Among five estuaries along the Southern
Gulf of St. Lawrence, Canada, our results suggest that the two survey methods yield
comparable results for species richness, diversity and evenness, yet beach seines yield
significantly higher abundance and different species composition. However, sampling
nearshore assemblages does not represent those in eelgrass beds despite considerable
overlap and close proximity. These results have important implications for how and
where macrofaunal assemblages are monitored in coastal ecosystems. Ideally, multiple
survey methods and locations should be combined to complement each other in
assessing the entire assemblage and full range of changes in coastal ecosystems, thereby
better informing coastal zone management
Comparative analysis of different survey methods for monitoring fish assemblages in coastal habitats
Impacts de la restructuration du réseau d’autobus de la ville de Québec sur l’accessibilité aux emplois des femmes et sur leur mobilité professionnelle
Le réseau d’autobus de la ville de Québec a subi une importante restructuration en 1992 avec la création du Métrobus et l’ajout de lignes express. L’objectif de cet article est de vérifier si la restructuration de ce réseau a permis d’améliorer l’accessibilité aux emplois des résidentes et de favoriser leur mobilité professionnelle. Les données des enquêtes origine-destination de 1991 et 2001 réalisées par le ministère des Transports du Québec et le Réseau de transport de la Capitale sont mises à profit. Les variations spatiales et temporelles des différents indicateurs montrent une diminution sensible des durées de déplacement et une amélioration de l’accessibilité aux emplois à partir de certains secteurs de la ville et ce, en dépit d’une diminution de la part modale de l’autobus, même dans les couloirs du Métrobus. Par ailleurs, la mobilité professionnelle des femmes semble avoir progressé dans plusieurs secteurs desservis par le Métrobus.When the Quebec City public transport system was reorganized in 1992, two specific transit services were set up: the “express” and the “Métrobus.” The aim of the paper is to determine whether the reorganization of this system improved employment accessibility for residents, especially women, and supported their professional mobility by making them progress on the labour market. We used data from 1991 and 2001 OD surveys. Spatial and temporal variations of various indicators show a reduction in travel time to work and an improvement in employment accessibility, but only for certain sectors of the city, and this in spite of a reduction in bus modal split between 1991 and 2001, even in the Métrobus corridors. In addition, women’s profes- sional mobility has progressed in several sectors served by the Métrobus even when general professional progression is taken into account
Modeling propensity to move after job change using event history analysis and temporal GIS
Residential choice behavior, Change of workplace, Decision-making, Event history analysis, Spatio-temporal modeling, Global and local spatial autocorrelation, C19,
Évolution de la mobilité des membres de familles monoparentales dans la région métropolitaine de Québec de 1996 à 2006 : comparaison entre les ménages matricentriques et patricentriques
Cette recherche vise Ă outiller les dĂ©cideurs pour dĂ©tecter les risques d’exclusion sociospatiale des familles monoparentales, afin de promouvoir des politiques publiques qui rĂ©duisent les iniquitĂ©s sociales en milieu urbain. Ces familles sont considĂ©rĂ©es comme l’un des groupes les plus dĂ©favorisĂ©s de la sociĂ©tĂ©. Cet article se concentre sur l’aspect spatial de l’exclusion sociale. L’objectif gĂ©nĂ©ral est d’analyser la variabilitĂ© des conditions et des contraintes de mobilitĂ© des mĂ©nages monoparentaux, Ă partir de l’hypothèse que les familles monoparentales dirigĂ©es par la mère ont un dĂ©ficit de mobilitĂ© par rapport Ă celles dirigĂ©es par le père, ce qui se traduirait par des vitesses de dĂ©placement infĂ©rieures chez les familles matricentriques. La mĂ©thodologie repose sur des tests statistiques de diffĂ©rences de moyennes et de proportions, des analyses centrographiques de rĂ©partition des lieux de rĂ©sidence et des analyses de rĂ©gression par quantile, en 1996, 2001 et 2006, dans la rĂ©gion mĂ©tropolitaine de QuĂ©bec. Les rĂ©sultats indiquent que les familles dirigĂ©es par la mère sont moins motorisĂ©es et leurs membres adultes utilisent moins l’automobile dans leurs dĂ©placements, ce qui contraint leur accessibilitĂ©. De plus, quand on fait intervenir des facteurs environnementaux, socioĂ©conomiques et spatiaux, ce dĂ©savantage de mobilitĂ© est significatif et persiste durant toute la pĂ©riode d’étude. La diffĂ©rence est particulièrement forte pour les dĂ©placements associĂ©s Ă des vitesses de dĂ©placement Ă©levĂ©es.This research aims to provide decision makers with reliable tools to evaluate the risk of socio-spatial exclusion of lone-parent families in order to promote public policies that reduce social inequities in urban areas. Lone-parent families are considered one of the most disadvantaged groups in society. This article focuses on the spatial aspects of social exclusion. The general objective is to analyse the variability in the mobility conditions and constraints faced by members of lone-parent households. The hypothesis is that lone-parent families headed by mothers have a mobility deficit compared to those led by fathers, which is reflected in lower travel speeds amongst the members of the former. The methodology is based on statistical tests of differences in means and proportions, centrographic analyses of the spatial distribution of residences, and quantile regression analyses for 1996, 2001 and 2006, in the Quebec City Metropolitan Region. The results indicate that households headed by mothers are less motorised and its adult members made a lower proportion of theirs trips by car, which is detrimental to their accessibility. Moreover, after controlling for environmental, socio-economic, and spatial factors, this mobility deficit remains statistically significant throughout the study period. This deficit is particularly larger in the trips associated with high travel speeds.La intenciĂłn de esta investigaciĂłn es dotar a los hacedores de polĂtica pĂşblica de elementos para poder detectar los riesgos de exclusiĂłn socio-espacial que corren las familias monoparentales y favorecer polĂticas pĂşblicas que reduzcan las iniquidades sociales en zonas urbanas. Esta clase de familias son consideradas como uno de los grupos más desfavorecidos de la sociedad. Este artĂculo se centra sobre el aspecto espacial de la exclusiĂłn social y analiza la variabilidad de las condiciones y restricciones de movilidad de los hogares monoparentales. La hipĂłtesis postula que las familias monoparentales dirigidas por la madre sufren de un dĂ©ficit de movilidad al ser comparadas con las dirigidas por el padre, lo que se reflejarĂa en velocidades de desplazamiento inferiores entre los miembros de los hogares matricentrales. La metodologĂa consiste en test estadĂsticos de diferencia en medias y proporciones, en análisis centro-gráficos de la distribuciĂłn de los domicilios y en análisis de regresiĂłn por quintiles para 1996, 2001 y 2006, en la regiĂłn metropolitana de Quebec. AsĂ, las familias dirigidas por la madre son menos motorizadas y sus miembros adultos utilizan menos el automĂłvil para desplazarse, lo que limita su accesibilidad. Además, al controlar por factores ambientales, socioeconĂłmicos y espaciales, el dĂ©ficit de movilidad es significativo y persiste durante el periodo analizado. El dĂ©ficit es más pronunciado en los trayectos asociados a velocidades de desplazamiento elevadas
The effects of land use planning on housing spread: A case study in the region of Brest, France
International audienceThis work provides a long-term study of housing development in the Brest region (France). Its main objective is to test the efficiency of the French laws and of urban planning bylaws to control housing development in the coastal zone. Based on the yearly status of available plots, a panel longitudinal analysis (1968-2009) is developed. It combines survival analyses with spatial-temporal diffusion indices, to assess their joint effects on the urban form evolution considering accessibility, proximity, spatial contiguity, temporal continuity, edge waves versus leapfrog growth, etc. That allows testing hypotheses about the diffusion processes, and the achievement of sustainable urbanism to increase density, promote adjacency and avoid urban sprawl and its detrimental effects on the environment and climate. The main finding is that national laws need land planning to deploy locally and that municipalities and stakeholders still prefer economic development over environmental conservation. That is putting emphasis on a restricted (short term) view of sustainable development