Measuring activity spaces of people, households and population segments Catherine Morency, P.Eng., Ph.D., assistant professor Groupe MADITUC Centre de recherche interuniversitaire sur les réseaux d’entreprise, la logistique et le transport (CIRRELT) Department of Civil, Geological and Mining Engineering Ecole Polytechnique de Montréal, P.O. box 6079, station Centre-Ville, Montréal, Qc, CANADA, H3C 3A7 email : cmorency@polymtl.ca Yan Kestens, Ph.D. Direction de Santé Publique de Montréal, research assistant professor Département de médecine sociale et préventive, Université de Montréal 1301, rue Sherbrooke est, Montréal, Qc CANADA, H2L 1M3 email : yan.kestens@umontreal.ca 1 Measuring activity spaces of people, households and population segments Catherine Morency and Yan Kestens Abstract This paper contributes to the discussions on activity location choice modelling by examining the concept of activity spaces. Actually, data from large scale OriginDestination surveys held in 1998 and 2003 in the Greater Montreal Area are used for the first time to quantify the use of space of more than 165,000 people nested in some 65,000 households. Systematic measures of daily activity spaces of individuals and households show that the number of locations used for daily activities have decreased during the 5 year period for every segment but that the area used to conduct these activities have increased. Acknowledgments The authors wish to acknowledge the transport authorities responsible for the conduct of large scale Origin-Destination surveys in the region, namely the AMT, MTQ, STM, STL and RTL. 2 Measuring activity spaces of people, households and population segments 1. Introduction Urban sprawl, socio-demographic evolution and car accessibility have modified the way people organize their daily behaviours in space and time. New concepts such as activity spaces have emerged to improve our understanding of the spatial patterns of individual travel behaviours. Activity spaces relate to “that part of the environment, which a traveller is using for his/her activities” (Axhausen et al., 2004). They can be assessed with various indicators, using confidence ellipses, kernel densities or convex hulls for instance. Still, the precise quantification of these activity spaces, for various population groups, requires significant amount of data on the activity behaviour. In order to contribute to the discussions on activity location choice, data from large scale Origin-Destination surveys held in 1998 and 2003 in the Greater Montreal Area are used, for the first time, to quantify and analyse the use of space of more than 165,000 people nested in some 65,000 households. The paper is organised as follows. First, research on the related domains is discussed. Then, the information system used to quantify the activity spaces of people and households is defined. Origin-Destination datasets are described as well as the concepts used to quantify activity spaces. Results issued from the processing of the two datasets are then presented and discussed. Research perspectives conclude the paper. 3 2. Background The modelling of activity location choice is still a big concern in the transport community. Up until recently, the spatial distribution of destinations was often neglected. However, notable work has been done in this domain in the recent years, mainly due to the important advances in spatial technologies and GIS (Geographic Information Systems). The growing availability of precisely geocoded databases regarding individual behaviours in space and time is also responsible for the emergence of multiple discussions on the topic. Consequently, concepts such as activity spaces or space-time prisms have emerged in order to enhance our understanding of activity-related travel behaviour, space consumption, and time management. A concomitant goal was to refine measures of accessibility. Literature on activity space often refer to the space-time prism of Hägerstrand (1970) which illustrates how a person navigates his or her way through the spatial-temporal environment. Many contributions were done by Kwan (1998, 1999, 2000) on the representation of activity spaces (concepts, tools and visualisation) and by Miller (1999, 2004) on accessibility measures. The observation of travel behaviours, in space and time, requires precise and exhaustive datasets (the lack of which explains why few works relate quantitative measures of the set of locations used by people and households). Numerous researches are however done to elaborate appropriate survey methods. Some authors point to the need to develop survey methods particularly able to unravel the activity planning process (Kreitz and Doherty, 2002 for instance). Incidentally, a new facet of activity location choice modelling has emerged in the recent years integrating the notion of social networks. One aim is to account for people’s social interactions in the acquisitions of activity locations. Methods pertaining to the analysis of social 4 networks are integrated to activity location choice modelling for this purpose (see for instance Carrasco and al., 2006, Axhausen, 2005 and 2006). Modelling the activity patterns of individuals while taking into account the household context is also part of current discussions; it is often referred to as withinhousehold interactions. Miller and Roorda (2003) present a household activity-travel scheduler calibrated using trip diary. Other research on households’ activity are discussed by Wets et al. (2000), Vadarevu and Stopher (1996), Jun and Goulias (1997). Some methodological and technological contributions are worth noticing. Buliung and Kanaroglou (2004) present an object-oriented, GIS-based environment that facilitates the visualisation, exploration and description of households’ activity patterns. Various measures can be compiled using this tool: central tendency and dispersion, convex hull and three-dimensional space-time paths. Free tools such as CrimeStat (Levine, 1996 and 2000) and GeoDa (Anselin et al., 2006) clearly help disseminate knowledge regarding spatial statistics. As mentioned earlier, even if activity location choice has been a critical modelling issue for some time, few works relate quantitative measures of activity spaces. From these, the various measures conducted using the Mobidrive six-week diary are worth noticing. Actually, such data offer a lot of observation for a particular unit of observation (a person) and allows measuring the variability of travel behaviour in space and time. Various works were conducted using this dataset: Schönfelder and Axhausen (2002) measure individual activity spaces using a series of measures, Srivastava and Schönfelder (2003) show the temporal variability of activity spaces, Kitamura et al., (2006) analyse the day-to-day variability of individual space-time 5 prisms, Susilo and Kitamura (2005) use the data to examine the features of individual’s action space and measure day-to-day variability. Walker (2004) discusses the difficulties of specifying the set of relevant alternatives for location choice modelling and explores the potential of parameterizing activity spaces instead of considering the whole area to define choice set. She demonstrates that there is a strong relation between the home-work corridor and the location of non-work activities. Kitamura et al. (1998) develop multinomial logit destination choice model and show that time of day, duration of activity and home location affect destination choice behaviours. Buliung and Kanaroglou (2006) examine the spatial characteristics of daily household activity-travel behaviours using an activity-travel survey from Portland, Oregon. They show that urban households do less daily travel and have smaller activity spaces. From this review, we see that the processing of large scale travel surveys to measure individual and household activity spaces is quite new and that there is a lack of quantitative measurement of this use of space. The current research is a primer to the systematic measure of activity spaces of people and households from two large scale surveys held in the Montreal Area. 3. Information system The Greater Montreal Area GMA has a long tradition of conducting large scale travel Origin-Destination (OD) surveys. Actually, OD surveys have been conducted regularly in the region since the early seventies. These surveys sample approximately 5% of the residing population and gather data regarding a weekday of urban travel. The interviews are conducted by phone and assisted by a CATI system since 1998 6 (Chapleau et al., 2001). Information on households (size, car ownership, home location, mobility), people (age, gender, driving license, main occupation) and trips for all household members (time of departure, purpose, mode sequence, transit path, highways/bridges, type of parking spaces, …) are gathered. Every interview relates to a specific weekday of the fall period (September to December). Details regarding these Origin-Destination household surveys can be found on the CIMTU web site (http://www.amt.qc.ca/cimtu). The OD datasets gather precisely geocoded information on the daily behaviour of residents and allow the analysis, in space and time, of their activities. Figure 1 gives a good idea of the spatial and temporal level of detail available in such datasets. This figure shows six temporal snapshots of the spatial distribution of people over the 5000 km2 area during a typical weekday. Figure 1. Chronology of the spatial location of mobile population during an average weekday (1998) – square kilometre cells (Morency and Chapleau, 2004) The richness of these surveys has often been demonstrated with respect to the modelling of travel behaviours (see for instance Morency 2004 and 2006). The current paper proposes new uses of the spatial data available regarding trips ends and seeks to validate its capacity to describe activity spaces of people and households during a typical day of fall. Actually, the two latest travel survey samples are processed for this purpose. Table 1 presents summary statistics for the two latest survey samples that are used for the analyses. As shown, the study of activity spaces will rely on the examination of the daily behaviours of more than 370 000 trips for which origin and destination points are precisely geocoded in space. The proportion of active people and households identifies the portion of the sample for which activity spaces can be examined (people are considered active if they did at least one 7 trip during the day they were surveyed, households are considered active if at least one of their member is active). Actually, the enumeration of activity location is possible for every active people. However, the measure of activity spaces using convex hull will be possible only for people or household visiting more than two locations. Table 1. Summary figures regarding the 1998 and 2003 travel survey samples 4. Measures of activity spaces Measures of activity spaces aim to summarize the use of the spatial environment of travellers as they conduct their activities. These measures are based on the set of points where activities are conducted, and may concern frequency, form, or network (routes) characteristics. The spatial measures presented below are computed using GIS tools (ArcGIS, PostGreSQL). Only urban locations within the survey area are considered for these estimations. As a former attempt to describe activity spaces of people and households using large scale travel surveys, the following measures are estimated both at the individual and household levels: Enumeration of activity locations: this consists in identifying the set of unique locations used, notwithstanding the number of times that it was visited during the day. This list includes the home location when it was observed at least once as origin or destination point. It is generally the case. Area and perimeter of convex hulls (CH): in the plane, the CH can be visualized as the shape assumed by a rubber band that has been stretched around a set of points and released to conform as closely as possible to this set. GIS functions are used to estimate the convex hull around the set of trip 8 ends of travellers. Area ( ACH ) and perimeter ( PCH ) are computed for this polygon. The Gravelius compactness coefficient is also estimated using area and perimeter as follows: CI P 2 A 0.28 P A . It approaches 1 when the shape of the CH is almost circular and increases with the elongation. Convex hulls with non-null areas can be estimated when the number of points is superior to 2. Corresponding measures were therefore computed for a subset of individuals and households which visited more than two locations. A schematic illustration of these concepts follows (see Figure 2). Figure 2. Schematic illustration of the activity spaces of people and households Eccentricity of CH with respect to home location: the mean centre of the polygon ( xCH , yCH ) expressing the CH is also estimated using GIS function. The distance between home location and the mean centre of the CH gives a first impression of the eccentricity of the activity locations with respect to home location. Its value does not inform on the spatial dispersion of the activity locations, it indicates whether the home location is central to the set of points used for out-of-home activities. 5. Results 5.1 5.1.1 Activity spaces of individuals Enumeration of activity locations Table 2 presents the average number of locations visited by a person during a typical weekday, and this for various population segments. Since it was estimated for both survey samples, it gives a first view of the evolution of activity spaces from 1998 to 9 2003. The main observation it that the number of locations has decreased for all the population segments and confirms that behaviours have evolved in the area. Table 2. Average number of locations visited by a PERSON during a typical weekday (1998 and 2003) As shown in Figure 3, the study of this indicator by age cohort and gender shows decreases in values for all groups. Women between 30 and 44 years old are those who visit the most locations per weekday. Figure 3. Average number of locations visited by weekday according to age and gender (1998 and 2003) The distribution of people according to the number of locations they visit by weekday finally allows seeing that the majority of them (around 70%) use only two different locations by days, one of them generally being the home location. Consequently, more than two thirds of the active people do only two trips per weekday. Figure 4 shows the frequency distribution for some distinctive population segments. For instance, more than 80% of the students visit only two locations by weekday while people owning a car are near 60% to visit only two locations. Figure 4. Frequency distribution of the number of activity locations visited on an average weekday for various population segments (2003 OD survey) 5.1.2 Features of convex hulls Area and perimeter have been estimated for 33 075 (862 100 weighed people) and 45 123 (958 300 weighed people) people for the 2003 and 1998 survey samples respectively. The resulting measures are further discussed. The following table presents summary results regarding the size of convex hulls for various population segments. First, we observe that activity spaces have become wider for all population segments. We also see that some population segments have 10 wider activity spaces than others. Actually, activity spaces increase as people live further; they also are wider for men, owner of a car and workers. Car unavailability seems to be the most important constraint to spatial dispersion of activity points. Compactness coefficients do not vary significantly between population segments. Home location appears to have the largest impact on the shape of activity space with average compactness coefficient varying between 1.446 for people residing in the CBD (Central Business District) to 1.804 for people living in the furthest suburbs. Table 3. Summary features of the convex hulls representing activity spaces of PEOPLE during a typical weekday (1998 and 2003) Average features of convex hulls do not however reflect the variability of the activity spaces of individual. Actually, in 2003, more than 25% of the people have convex hulls’ areas smaller than 1 square kilometre and 50% smaller than 5 square kilometres. Hence, convex hulls are quite variable. The following figure (Figure 5) shows the cumulative distribution of people of various segments according to the area of the convex hull. This distribution facilitates the observation of differences between these segments. From this graph we observe that more than 70% of the people without a car have CH smaller than 5 square kilometres while this figure drops below 50% for outer suburbs residents. Figure 5. Cumulated people according to area of convex hull (2003 OD survey) 5.1.3 Eccentricity measures The average distance between the home location and the mean centre of the CH gives a first impression of the eccentricity of the set of activity points with respect to the home location. As shown in Figure 6, eccentricity varies across population segments. As could be expected, it is smaller for children and elderly people. Hence, 11 features such as living in outer suburbs, owning a car or being a worker increases this measure. Average eccentricity measure varies from 2.203 in the CBD to 6.530 in the outer suburbs. Again, not owning a car seems to structure activity locations around the home location. Figure 6. Average distance between home location and mean centre of convex hull for various population segments (2003) 5.2 5.2.1 Activity spaces of households Enumeration of activity locations The enumeration of all the activity locations used by the members of a household is summarised in Table 4 for both datasets. As was observed for individuals, the average number of locations used during a typical weekday has decreased from 1998 to 2003. Although the average household size did concomitantly decrease during that same period, segmented estimations by household size confirm the decrease in the average number of visited locations for every specific size considered. Table 4. Average number of locations visited by an HOUSEHOLD during a typical weekday (1998 and 2003) Figure 7 shows the average number of different locations visited by weekday by the households according to their size and car ownership. Grey histogram and right site y-axis further provide the weighted number of households within each segment. The two datasets confirm the importance of car ownership for location choice since it increases the number of visited locations notwithstanding the household size. Actually, in average, an additional car will result in 0.29, 0.26, 0.25 and 0.31 new activity location by weekday for households of 1, 2, 3 and 4 people and more respectively. 12 Figure 7. Average number of locations visited by weekday (1998 and 2003) and number of households (2003) according to size and car ownership (2003) 5.2.2 Features of convex hulls Households’ convex hulls were estimated using a sample of 36 753 households (929 700 weighed households) and 43 664 households (912 300 weighed households) for 2003 and 1998 OD surveys respectively. Table 5 presents summary results regarding the size of convex hulls for various types of households. Differences between household segments are straightforward: activity spaces (area and perimeter) increase as household size and car ownership increase and as home location gets further into suburban areas. However, the key observation is certainly the fact that all activity spaces increase during the 5 year period even if the number of locations has decreased during the same period. This is a quite a relevant finding; actually although the average number of locations visited by a given household decreases between 1998 and 2003, the size of the activity space increases, denoting a dispersion in activity locations away from home. Table 5. Summary features of the convex hulls representing activity spaces of HOUSEHOLDS during a typical weekday (1998 and 2003) Figure 8 presents the cumulated proportion of households (of various segments) according to the area of the convex hull (for the 2003 survey). This graph is particularly interesting in showing how much convex hull sizes do vary within a category. For instance, almost 70 % of households owning 2 cars or more have areas of convex hulls larger than 10 square kilometres while only 20% of those not owning any car. The graph also clearly illustrates the effects of household size and relative home location. Considering the fact that household sizes and location are not independent, part of the differences is due to the fact that households are larger 13 further away from downtown. However, areas, perimeters and CI vary considerably within household size segments according to their home location. For a two-person household, the average area varies from 19.6 to 25.5 km2, the perimeter from 23.6 to 44.9 km and the CI from 1.49 to 1.70 depending on whether home is located in the Montreal Island or in the Outer suburbs respectively. Figure 8. Cumulated households according to area of convex hull (2003 OD survey) 5.2.3 Eccentricity measures The study of households’ activity spaces is concluded by the examination of eccentricity with respect to home location. The following figure (Figure 9) gives average distances between home location and mean centre of convex hull for various population segments. This measure of eccentricity is quite stable within households of two people and more. It however varies considerably according to home location and car ownership. For instance, every additional car will add 1.1 km to this eccentricity for 2 people households living in the near suburbs and more than 2.1 km for the ones living in outer suburbs. Figure 9. Average distance between home location and mean centre of convex hull for various household segments (2003) 6. Discussion and concluding remarks This paper has demonstrated the capacity of large-scale household travel surveys to describe the activity spaces of individuals and households in the GMA for two different time frames, using quantitative measures relating to the convex hull of the activity locations, and eccentricity in regard to place of residence. Here are some of the findings and conclusions. 14 6.1 Individual level We observe that activity spaces are very variable, according to gender, car ownership and occupation. Furthermore, great variations do exist within each sub-category, and average values do not reveal this variation. Also, differences in Convex Hull size between groups are much more important than differences in the number of visited locations between groups. Although the differences in the number of destinations are small between segments, the differences in the activity space (area, perimeter) are important. Between 1998 and 2003, the number of visited activity locations has decreased for every identified segment and within each age category. Gender differences have reduced for almost all age categories, in certain cases, differences have even been inverted (in the 65 to 74 year old category, women visit more locations than men in 2003, the inverse being true in 1998). A previous study has shown that the number of trips per day has decreased but that the average duration of constrained activities has increased (duration of work and study activities) (MADITUC, 2004). The hypothesis that is currently being investigated is that unconstrained activities such as shopping and leisure are moving to weekends since weekdays are getting busier with work and study activities. During the same 1998-2003 period, size of activity areas has however increased within each subgroup. The five year period shows a decrease for all identified subgroups and between men and women for nearly all age groups in the number of visited activity locations. Whereas both the number of visited activity locations has decreased in every identified subgroups and gender differences have shrunken, concomitantly, the size of the activity space, as measured by the convex hull area and perimeter have increased for all subgroups. 15 It seems more difficult to comment on the changes between 1998 and 2003 in the shape of activity spaces. Globally, the compactness index has slightly decreased (from 1.582 to 1.565), but in certain subgroups, it has slightly increased (students, near suburbs). Further measures are needed to comment more precisely on the changes in shape of activity space. 6.2 Household level Most of the individual-level comments could apply ate the household level. It is quite obvious that the greater the household, the bigger the convex hull, or the greater the number of destinations. However, car access within the household, when controlling for household size, seems to be an important determinant in space use. Similarly, home location is strongly related to the size of the convex hull for a fixed household size: the further the home location from the CBD, the larger and less compact the space used for out-of-home activities. 6.3 Work in progress Work on the measure of activity spaces using large scale Origin-Destination surveys is ongoing. The following themes are under examination: Estimation of other indicators namely the shortest string required to link all the activity points and the spatial distribution measures available in spatial statistic software. Hence, the modelling of activity in space and time will be examined using both individual and household characteristics, as well as environmental measures around place of residence. In order to enhance the information available from such datasets, methodological developments are aimed at constructing typical weeks of 16 travel (Mondays vs Tuesdays, etc.) using the day of travel to construct independent survey samples. Activity spaces will be compared for those five types of days. Moreover, data mining techniques will be used to identify groups of population and household presenting similar features and to construct synthetic people to whom 5-days spatio-temporal behaviours will be assigned. 6.4 Conclusion The measure of activity spaces is a promising avenue to better assess the location choice process by people and households. Large-scale Origin-Destination survey data have the capacity to reveal various aspects of the daily use of space to perform out-of-home activities. Although these cross-sectional surveys provide information on a single day only, the important sample size makes it possible to observe the typical behaviour of people during a weekday. Surely, multi-day surveys such as Mobidrive (Schlich and Axhausen, 2003) are complementary, as they specifically measure the activity space of people over a longer period of time. Consecutive burden on the respondent however constraints these studies to small sample sizes. In our case, methodological difficulties related to the big sample size point to the need for developing new tools to facilitate the measurement of various indicators. Refining measures and analyses of activity spaces will help predict the consequences of observable trends (household size, increasing participation of women to the workforce) and policies (home location vs activity spaces and urban sprawl phenomena) on the structure of daily behaviours in space and time. 17 7. References Anselin, Luc, Syabri, Ibnu, Kho, Youngihn (2006). GeoDa: An Introduction to Spatial Data Analysis, Geographic Analysis 38, pp.5-22. Axhausen K.W. 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Wets, Geert, Vanhoof, Koen, Arentze, Theo, Timmermans, Harry (2000) Identifying Decision Structures Underlying Activity Patterns An Exploration of Data Mining Algorithms, Transportation Research Record 1718, TRB, Washington D.C., pp.1-9 20 Tables Table 1 Sampling rate Households % active households People % active people Trips 1998 4.64% 65,200 91.0% 164,100 79.2% 383,800 2003 3.83% 58,000 90.10% 173,300 79.7% 326,500 21 Table 2 Unit: PERSON Average number of locations visited by weekday 1998 2003 People 2.48 2.40 Gender Men 2.45 2.37 Women 2.51 2.42 Main occupation Worker 2.59 2.46 Student 2.31 2.23 Car ownership Yes 2.60 2.49 No 2.35 2.27 Home location Montreal Island 2.52 2.43 Near suburbs 2.49 2.40 Outer Suburbs 2.41 2.34 22 Table 3 Area People 17.39 Men Women 20.17 14.62 Worker Student 22.58 9.74 Yes No 22.38 8.55 Montreal Island Near suburbs Outer Suburbs 11.55 17.35 28.50 Features of convex hulls 1998 Perim Comp.Ind. Area 23.56 1.582 Gender 25.34 1.580 21.78 1.595 Main occupation 28.15 1.659 17.50 1.570 Car ownership 27.64 1.636 16.33 1.564 Home location 18.76 1.546 23.07 1.551 33.02 1.732 23 2003 Perim Comp.Ind. 19.50 24.68 1.565 23.05 16.07 26.78 22.64 1.562 1.582 24.37 10.36 28.98 18.21 1.644 1.584 24.60 9.15 28.72 16.48 1.621 1.526 12.27 17.53 33.52 19.10 23.77 35.09 1.527 1.590 1.697 Table 4 Unit: HOUSEHOLD Average number of locations visited by weekday 1998 2003 Households 3.27 3.05 Size 1 person 2.10 1.92 2 people 2.94 2.80 3 people 3.87 3.74 4 people + 4.82 4.72 Car ownership No car 2.17 2.07 1 car 3.16 2.87 2 cars 4.07 3.76 3 cars + 4.67 4.50 Home location Montreal Island 3.11 2.94 Near suburbs 3.46 3.17 Outer Suburbs 3.46 3.19 24 Table 5 Unit: Area Households 35.63 1 person 2 people 3 people 4 people + 15.90 28.51 38.77 50.43 no car 1 car 2 cars + 7.93 23.95 56.68 Montreal Island Near suburbs Outer Suburbs 21.58 35.64 61.37 HOUSEHOLD Features of convex hulls 1998 Perim Comp.Ind. Area 31.22 1.46 Size 20.29 1.42 29.27 1.53 33.54 1.51 37.08 1.46 Car ownership 14.96 1.49 26.89 1.54 40.93 1.52 Home location 23.73 1.43 30.61 1.44 45.37 1.62 25 2003 Perim Comp.Ind. 38.60 32.74 1.48 16.47 31.10 42.49 54.81 21.19 30.66 35.11 38.85 1.46 1.54 1.51 1.47 8.31 24.67 59.18 15.24 27.34 42.25 1.48 1.54 1.54 22.38 35.85 67.23 24.29 31.04 47.83 1.44 1.45 1.63 List of illustrations Figure 1. Chronology of the spatial location of mobile population during an average weekday (1998) – square kilometre cells (Morency and Chapleau, 2004) .................. 7 Figure 2. Schematic illustration of the activity spaces of people and households ....... 9 Figure 3. Average number of locations visited by weekday according to age and gender (1998 and 2003) ............................................................................................. 10 Figure 4. Frequency distribution of the number of activity locations visited on a average weekday for various population segments (2003 OD survey)..................... 10 Figure 5. Cumulated people according to area of convex hull (2003 OD survey) .... 11 Figure 6. Average distance between home location and mean centre of convex hull for various population segments (2003) ..................................................................... 12 Figure 7. Average number of locations visited by weekday (1998 and 2003) and number of households (2003) according to size and car ownership (2003) .............. 13 Figure 8. Cumulated households according to area of convex hull (2003 OD survey) .................................................................................................................................... 14 Figure 9. Average distance between home location and mean centre of convex hull for various household segments (2003) ..................................................................... 14 26 5h00 9h00 12h00 15h00 18h00 20h00 27 CH P1 xCH P , yCH P 1 1 Hi CH H i Hi xCH Hi , yCH Hi CH P2 xH i , y H i xH i , y H i xCH P , yCH P 2 Activity spaces of people 2 Activity spaces of households 28 29 Men-98 Women-98 Men-03 Women-03 75 y.o.+ 70-74 y.o. 65-69 y.o. 60-64 y.o. 2.1 55-59 y.o. 2.2 50-54 y.o. 45-49 y.o. 40-44 y.o. 35-39 y.o. 30-34 y.o. 25-29 y.o. 20-24 y.o. 15-19 y.o. 10-14 y.o. 5-9 y.o Average number of locations visited by weekday according to gender and age 2.8 2.7 2.6 2.5 2.4 2.3 2.0 Distribution of people according to the number of locations visited by weekday 90% % people in segment 80% Car ownership: Yes 70% Car ownership: No 60% Main occupation: Worker 50% Main occupation: Student 40% 30% 20% 10% 0% 1 2 3 4 5 6 Number of locations visited by weekday 30 7 8+ Cumulated people according to area of convex hull (2003) 100% 90% 80% 70% 60% Men Women 50% Owns a car No car 40% Worker 30% Student Montreal Island 20% Near suburbs 10% Outer Suburbs 0% 0 5 10 15 20 25 30 Area of convex hull (km 2) 31 35 40 45 50 Average distance between Home location and Mean center of Convex hull for various population segments (2003) 9.0 Home - Convex Hull distance (km) 8.0 Outer Suburbs 7.0 Ow ns a car 6.0 5.0 Worker Near suburbs 4.0 3.0 No car Montreal Island 2.0 1.0 0.0 5-9 y.o 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75 y.o. y.o. y.o. y.o. y.o. y.o. y.o. y.o. y.o. y.o. y.o. y.o. y.o. y.o.+ 32 Average number of locations visited by weekday by households according to size and car ownership 2003 5 250,000 1998 1 pers. 2 people 3 people 33 4 people + 3 cars + 2 cars 1 car 0 car 3 cars + 2 cars 0 1 car 0 0 car 50,000 3 cars + 1 2 cars 100,000 1 car 2 0 car 150,000 3 cars + 3 2 cars 200,000 1 car 4 Number of households (2003) 300,000 HH 2003 0 car Average number of locations 6 Cumulated households according to size of convex hull (2003) 100% 90% 80% 70% 60% Montreal Island 50% Near suburbs 40% Outer suburbs 30% 1 person 4 people + 20% no car 10% 2 cars + 0% 0 10 20 30 40 50 2 Area of convex hull (km ) 34 60 70 Average distance between home location and mean center of convex hull for various household segments (2003) Montreal Island Near suburbs 12.0 Outer Suburbs 10.0 8.0 6.0 4.0 2.0 1 pers. 2 people 3 people 35 4 people + 3 cars + 2 cars 1 car 0 car 3 cars + 2 cars 1 car 0 car 3 cars + 2 cars 1 car 0 car 3 cars + 2 cars 1 car 0.0 0 car Home-Convex Hull distance (km) 14.0