Opening the black box of cargo bike users’ route choice
Yuki Yamamoto
Research Master Urban Studies
11129263
yuki.yamamotog@gmail.com
Supervisor: Professor Marco te Brömmelstroet
Second reader: Professor Luca Bertolini
02-06-2017
Opening the black box of cargo bike users’ route choice
Abstract
Cargo bike, bicycle made to carry both goods and people, is becoming increasingly common as an alternative to automobiles in urban areas. Due to a large and heavy body, cargo bikes often face infrastructure problems even in the presence of cycling infrastructure, thus limiting the possibilities of route choice. Infrastructure quality and route choice of cyclists have been well-studied, but often solely based on a quantitative approach, leading to tools such as BLOS, bicycle level of service. Because there are various types of cargo bikes used for a wide range of purposes, route choice of cargo bike users is difficult to generalize. This study combines quantitative and qualitative approaches to explore what is important for cargo bike users’ route choice and how this knowledge can be effectively used for planning. The result suggests that while some general preferences exist, route choice involves complex dynamics that statistics cannot explain, and is also influenced by the city context, making a study tailored to the local context essential. In addition to “what” is important for cargo bike users, understanding “why” it is important allows a more flexible, inclusive planning that is becoming more and more necessary. (192 words)
Key words
1. Introduction
Cargo bikes - bicycle (including tricycle hereafter) made for transportation of goods and people, are becoming more and more popular in urban areas both for business and personal usage. In Europe, where 80% of the population are predicted to be living in or near a city (European Commission, 2014), cargo bikes are receiving increasing amount of attention as an alternative way of urban mobility, which accounts for 40% of all CO2 emissions of road transport ("Urban mobility - Mobility and Transport - European Commission", 2015). Light-weight cargo bikes that can carry up to 250kg have been used in various cities already, and they are functioning as a reliable, fast and cheap way of delivering goods (Maes & Vanelslander, 2012). On average, 51% of all motorized trips involving transportation of goods in European cities is estimated to be possible by bikes or cargo bikes (Cyclelogistics, 2014).
One advantage of cycling is that it allows flexible route choices, and one can reach the destination more directly (Manum & Nordstrom, 2013), and having more route choices contributes to this. A great amount of exposure to air pollution can also be avoided by choosing an appropriate route (Hertel, Hvidberg, Ketzel, Storm, & Stausgaard, 2008), and this is an important issue to consider for cargo bike users, who may need more breathing due to the extra weight of the bicycle and the luggage. This shift towards sustainable city logistics needs to be supported by provision of material infrastructure, which is focused in this study, as well as non-material infrastructure such as incentives and urban governance such as zero-emission zones (Schliwa, Armitage, Aziz, Evans, & Rhoades, 2015). With the increasing number of cyclists, infrastructure can cause safety and congestion problems if appropriate improvements are not made (Gustafsson & Archer, 2013). Compared to other means to improve cycling experience, infrastructure improvements can be made more easily since public policy and investment can influence infrastructure directly (Dill & Gliebe, 2008).
Various tools have been produced and researched for planners to evaluate and improve infrastructure for cycling, and many of them try to quantify the level of suitability for cycling based on various road attributes such as the type of cycling facility, traffic volume, speed limit, and so on. Models developed for this purpose often have quantitative nature, allowing little room for qualitative input. These tools are usually based on the route choice preferences of cyclists, but most of the researches have focused on normal bicycles and not cargo bikes. Needs of cargo bike users may differ from those of normal bike users, and this explorative study aims at understanding the route choice preferences of cargo bike users and how this knowledge can be effectively used in the planning process. Therefore, the research question is as follows:
How do infrastructure qualities relate to route choice preferences of cargo bike users, and how can this knowledge be used to inform planning?
To answer this question, the following sub-questions are answered: (1) What are the stated route choice preferences of cargo bike users? (2) How do these stated preferences relate to the route choice in reality? (3) How can this knowledge be used for planning? Main concepts of route choice and cycling suitability will be explained through existing literatures in the next section. Then, the method used in the research (case study, survey, interview) will be described in detail in the third section. Results will be shown and analyzed in the following section, leading to the conclusion with overall findings and suggestions for policy making.
2. Route choice and cycling suitability evaluation
The first step of the research was to explore the already-known knowledge about cyclists’ route choice preferences and the methods to evaluate cycling suitability based on the preferences. Key words used in the literature review include but are not limited to the following: cyclist, route choice, preference,
infrastructure, and level of service. Literatures that appeared with these keywords were first explored, and some of the relevant literatures referred to in them were further collected. Some of the literatures were only explored to grasp the approach taken and the results found without much attention in detail, especially in case of an engineering/mathematics oriented literatures which require an extensive knowledge of these fields. In all of the literatures, focus was put on variables, methods and the result. Route choice of cyclists and the motivation behind it have been widely discussed in the field of transportation planning as well as other fields such as psychology (Ma, Dill, & Mohr, 2014; Stefansdottir, 2014), sociology (Garrard, Rose, & Lo, 2008), and engineering (Callister, & Lowry, 2013; Ehrgott, Wang, Raith, & van Houtte, 2012; Priedhorsky, Pitchford, Sen, & Terveen, 2012). Route choice is often associated with the motivation for cycling, and lack of route choice may result in less accessibility to destination (Winters, Brauer, Setton, & Teschke, 2010), resulting in discouraging bicycle trips. Various attempts to understand why cyclists choose certain routes have been made, but there seems to be no agreement among researchers. While some researchers (Koh & Wong, 2013; Li, Wang, Liu, & Ragland, 2012; Menghini, Carrasco, Schüssler, & Axhausen, 2010) focus on external factors such as cycling environment, infrastructure and legal system, others examine internal factors such as the demography of the user (Bernhoft, & Carstensen, 2008; Garrard, Rose, & Lo, 2008) and the purpose of the trip. Some (Caulfield, Brick, & McCarthy, 2012; Ehrgott, Wang, Raith, & van Houtte, 2012; Krenn, Oja, & Titze, 2014; Segadilha, & Sanches, 2014; Sener, Eluru, & Bhat, 2009) combine both. Cycling environment influences the route choice through the level of safety, comfort, and effort required during the trip. Some argue that there are elements that are more important than any other of them; Caulfield, Brick, & McCarthy (2012), and Suzuki, Kanda, Doi, & Tsuchizaki (2012) claim that directness and the short travel time is the strongest motivation, but Krenn, Oja, & Titze (2014) found that the route that is actually used is 6 to 16% longer than the shortest possible route, based on a research in various cities in the world. Broach, Dill, & Gliebe (2012) add to this that the purpose of the trip also matters in route choice. They found that commuter cyclists have stronger preference in shortness of the route than cyclists with non-utilitarian purposes.
Safety is another important aspect of route choice, and numerous studies have been conducted in this regard. Segadilha, & Sanches (2014) argue that safety-related factors such as traffic speed, number of heavy vehicles and street lighting are the first priorities to cyclists. The presence of dedicated cycling facility has been found important (de Sousa, Sanches, & Ferreira, 2014), and Jensen (2007) and Kang, & Lee (2012) add to this the importance of its width. Cyclists are found to prefer cycling facilities separated from car traffic (Caulfield, Brick, & McCarthy, 2012; Hull, & O’Holleran, 2014), while Ton, Cats, Duives, & Hoogendoorn (n.d.) found that in Amsterdam cyclists do not value separation so much. There are other factors to consider such as traffic lights (Broach, Dill, & Gliebe, 2012) and space available around cyclists apart from cars (Stewart, & McHale, 2014).
Another aspect of route choice is comfort, which is related to safety, since perception of safety leads to comfort, and that of danger to uncomfortableness. Congested space, intersections, and frequent turns all contribute to decreasing comfort, since they require much more attention of cyclists, while a combination of continuous space and calm traffic with moderate complexity gives comfort to cyclists (Stefansdottir, 2014). According to Koh, & Wong (2013), cyclists prefer a route that is comfortable, close to roadways, with other cyclists and pedestrians, flat terrain, and good scenery. Road condition such as the surface material and condition is also a factor often discussed (Kroll, & Sommer, 1976). On-street parking facility also affects cyclists’ route choice (Sener, Eluru, & Bhat, 2009). Trade-off is an important aspect to consider in route choice, since cyclists generally travel longer in order to avoid certain road attributes (Scarf, & Grehan, 2005; Tilahun, Levinson, & Krizek, 2007).
Cyclists have to accept trade-off among various aspects of the route, and a holistic analysis needs to be done to understand this complex dynamic. Cyclists are usually happy to take a detour in return for a more preferred environment for cycling, and relative rather than absolute deviation distance should be considered in the calculation (Broach, Dill, & Gliebe, 2012).
Over the last decades, various methods have been developed in order to holistically understand the route choice of cyclists, and overcoming the difficulty of trade-off seems to have been the focus of development of such methods. Civil engineers have tried to evaluate the cycling suitability of road segments to better understand why cyclists choose certain routes. Level of service (LOS), which measures quality of infrastructure, is one of such methods, and can be defined as a “qualitative measure that needs to reflect user perceptions of the quality of service, comfort and convenience (Zhang, & Prevedouros, 2011)”. It was originally developed in the United States as a tool to analyze quality of roads for automobiles, but it has been modified and applied for other modes of transportation (Hull, & O’Holleran, 2014). LOS for automobiles is too narrowly focused and fails in evaluating road quality for cyclists, and therefore bicycle level of service (BLOS) was created (Huff, & Liggett, n.d.). BLOS can be defined as “the level of satisfaction that a bicyclist would experience while riding on a bicycle road (Kang, & Lee, 2012)”. Sprinkle Consulting (2007) has developed a BLOS formula that can be used in North America overall, but due to the goal of being generalizable and applicable in a wide range of contexts (Callister, & Lowry, 2013), conventional BLOS models tend to fail to reflect the actual preferences. Many BLOS studies consider bicycles as equal to vehicles (Asadi-Shekari, Moeinaddini, & Zaly Shah, 2013), and therefore the varieties in the cyclists cannot be properly reflected. Lack of validation of BLOS leads to questionable results, and inability to accommodate various types of cycling space reduces the power of this tool. At the same time, attempts in including personalized preferences and adjusting to the innovative and changing environments around cycling infrastructure can be resource-intensive and time consuming (Huff, & Liggett, n.d.). BLOS or similar type of approaches are often used for route prediction, but they usually only take into account time and distance. Incorporating personal preferences would make the prediction more accurate (Priedhorsky, Pitchford, Sen, & Terveen, 2012). Jensen (2007) developed a method to calculate BLOS in the Danish context, where generally there are more types of cycling facilities than in North America. This research explores how the knowledge of cargo bike users’ route choice preferences can be effectively used for planning.
3. Research design
In order to examine the value of personalization of analyses (Huff, & Liggett, 2014), the study takes a form of comparative case study using two cities with different cycling context. Amsterdam and Stockholm were chosen as cases in this research. Amsterdam is known as a cycling city of the world, and infrastructure is designed for various types of bicycles. Such high usage of bicycles and extensive provision of cycling infrastructure can rarely be seen anywhere else perhaps except Copenhagen, and this is considered an extreme case (Gerring, 2006). Cycling in the city does not involve many constraints in terms of route options since the city is flat and there are not many geographical obstacles. Stockholm, on the contrary, is a city where the number of cyclists is on a rapid rise in the last decade, and cycling infrastructure is not always in existent. Route options are often significantly limited by water and varying terrain. These cities, a mature cycling city and a developing cycling city, will be compared to explore to what extent route choice preferences of cargo bike users can be generalizable and how the knowledge can be transferred to planning.
3.1 Overall preferences
First of all, to answer the first sub-question, an online survey was conducted to examine the generalized route choice preferences of cargo bike users. Stated preferences rather than observed preferences (such as traffic volume of cyclists) were enquired because cyclists only start using a route if its condition is perceived safe and comfortable, and their perception should be at the focus of analysis (Ma, Dill, & Mohr, 2014). Anyone who uses a cargo bike (any type of bicycle that is larger than a normal bicycle) in each city was able to participate. The survey link was distributed for about six weeks in each city. The survey consisted of two parts: the first part regarding the usage of cargo bikes and the second part about the route choice preferences. The usage of cargo bikes refers to the type of cargo bike (two-wheel cargo bike, three-wheel cargo bike, trailer with a normal bicycle, extra-large cargo bike, recumbent / wheelchair bike, other), purpose of usage (commuting, carrying goods for private usage, carrying goods for work, carrying children, other), and frequency of usage (almost every day, 4-5 days a week, 2-3 days a week, once a week or less). Route choice preferences were enquired quantitatively, and the importance of each infrastructure element (Table 1) was surveyed with a Likert scale with 10 alternatives. In the end of the survey, several open-ended questions were included to allow for flexible answers. These questions were focused on infrastructure issues that people face while using a cargo bike, and were intended to give insights for the potential interview topics and expand the scope of this survey.
Measurable variables from the previous studies were first selected, and relevant ones were further selected based on the local context in each city. “Intersection design” was added despite its difficulty to measure because it has not appeared previously even though it is part of the planning process.
Table 1
Variables in the study
Variable Abbreviation Stockholm Amsterdam
Type of infrastructure Type • •
Width of cycling space Width • •
Smoothness of road surface Smoothness • •
Straightness Straightness • •
Absence of parking Parking • •
Traffic volume (car) Car • •
Traffic volume (heavy vehicle) Heavy vehicle • •
Traffic volume (bicycle) Bicycle • •
Traffic volume (pedestrian) Pedestrian • •
Speed limit Speed limit • •
Number of traffic lights Traffic light • •
Intersection design Intersection • •
Smooth surface connection Gap •
Brightness Brightness • •
Upward steepness Steepness • •
The survey was conducted online, in order to facilitate participation. The survey link was spread both online and in person. In the former case, channels such as social media, cargo bike shops, businesses using cargo bikes, and bike-related organizations were used. In the latter case, for the efficiency of reaching the target group, focus was put on streets with large number of cyclists and schools where many parents drop off / pick up their children with a cargo bike. 206 valid responses in Stockholm and 121 in Amsterdam were collected.
The result of the survey was analyzed with SPSS. First of all, general route choice preferences were analyzed using the Likert-scale based questions, and the importance of each infrastructure element was ranked, using measurements of central tendency (mean, median) and rate of high-score answers (those who selected “8” or higher out of 10 alternatives from 1 to 10). Whether Likert-scale data can be treated as continuous rather than ordinal values has been under a long debate among researchers, and in order to reduce the bias based on the selection of measurement method, these three evaluation methods were used. Group differences were then analyzed based on the cargo bike usage information, in order to examine how differences in usage can influence route choice preferences. Respondents were categorized into dichotomous groups, as indicated in Table 2. Group differences were then analyzed based on infrastructure elements, type of cycling space, importance of width for each type of cycling space, and tolerance for speed limit (Table 3). Unlike the case of general central tendency, which only involves simple mathematical operations, analyses of group differences involve more sophisticated statistical operations. Because parametric tests tend to have stricter assumptions that the data have to satisfy, and the appropriateness of using parametric test for Likert-scale data has been under debate, a non-parametric test (Mann-Whitney U test) was used for the analysis.
Table 2
Survey analysis grouping
Group type Group 1 Group 2
Number of wheels1 Two Three
Purpose (commuting)2 Frequently commutes Infrequently commutes Purpose (carrying goods
privately)2
Frequently carries good privately Infrequently carries goods privately
Purpose (carrying goods for work)2
Frequently carries goods for work Infrequently carries goods for work
Purpose (carrying children)2
Frequently carries children Infrequently carries children
1 “Two-wheel” group includes “two-wheel cargo bike”, and “three-wheel” group includes “three-wheel cargo bike”, “trailer with a normal bicycle”, “recumbent bike / wheelchair bike”, and “extra large cargo bike”. 2 “Frequently” refers to two days a week or more, and “infrequently” refers to one day a week or less, or never.
Table 3
Topics for group difference analysis
Topic Object of evaluation Possible answers
Infrastructure elements
14/15 elements listed on Table 1 1 (not important at all) to 10 (crucially important)
Type of cycling space
One-way bike path with physical separation Very favorable Favorable Neutral Unfavorable Very unfavorable Two-way bike path with physical
separation Bike lane
Road shared with cars Width for
cycling space
One-way bike path with physical separation
Not important at all Not so important Somewhat important Important
Very important Two-way bike path with physical
separation Bike lane
Road shared with cars Speed limit
tolerance
Bike lane Stockholm Amsterdam
Road shared with cars 20km/h or less
30km/h 40km/h 50km/h 60km/h 70km/h or more I do not care 20km/h or less 30km/h 40km/h 50km/h or more I do not care
3.2 Dynamics of actual route choice
The second phase of the research was designed to answer the second sub-question, where cargo bike users were interviewed for an in-depth analysis of route choice decision making process. The main aim was to better understand the trade-offs among various elements of cycling environment, and what conditions influence the preferences. Interviewees were selected from the survey respondents, based on their wish to participate in an interview. The interview took a form of semi-structured interview where only the topics were standardized and the phrasing of each question depended on the context of each interviewee’s cargo bike usage.
The interview included four topics. The first topic was to know where the interviewee rides a cargo bike, and therefore involved the discussion of which route is taken and why the route is chosen over other options. For a better understanding of the situation, the interviewee was asked to submit the route information prior to the interview, and the road condition was checked either by cycling on the route or through Google Map street view. The second topic was on issues that the interviewee faces while using a cargo bike. The third topic was the differences between using a cargo bike and a normal bike, in order to better understand to what extent the issues brought up in the interview are specific to cargo bikes. The last topic was the application of preferences in reality, and the interviewee was asked to provide an example of best and worst road segment in the city for using a cargo bike. The interview topics are listed in Table 4. Seven and four cargo bike users with a mixture of different types of cargo bikes and usage purposes were interviewed in Stockholm and Amsterdam respectively, in order to incorporate various perspectives.
Table 4
Interview topics and questions (cargo bike users)
Topic Question
Usage information
When do you use a cargo bike, and for what purpose? What kind of cargo bike do you use?
Route information
Which route do you take? (asked prior to the interview) Why do you take this route?
What do you like and dislike about this route? Does the route differ sometime? When and why? Are there road segments you try to avoid? Normal bike –
cargo bike difference
Do you also use a normal bike? Do you choose a different route?
What kind of difficulties do you face even with a normal bike? What are the problems specific to your cargo bike?
Application of preferences
What road segments in the city are best/worst for your cargo bike (as examples)?
Why is it good/bad?
Other What are other important aspects for your route choice?
3.3 Knowledge transfer to planning
Answering the third sub-question involved interviewing city planners with the aim of exploring how the knowledge acquired in the previous steps can be transferred in city planning. Despite many attempts to quantitatively analyze the route choice of cyclists with a standardized method, this approach often fails in explaining why certain routes are chosen. The interview aimed to evaluate the applicability of such an approach for planning in the context of each city.
The interview consisted of four parts: case study, planning procedure, introduction of BLOS, and reflection. City planners working for cycling policy and/or infrastructure were selected for the interview. The first part of the interview was intended as an exercise for the planner (interviewee) to introduce the topic of route choice. Prior to the interview, the interviewee was asked to guess a route taken by one of the cargo bike users interviewed in the previous research phase, based on the given information of the start/end points of the trip on a map. In the interview, the planner was asked about the reasoning behind the guessed answer, followed by the revelation of the actual route taken and discussions of potential issues on the route. Second part of the interview focused on the process of planning for bikes, with the aim of understanding what is done and how it is done in each city. Emphasis was put on if and how infrastructure evaluation is done. The idea of BLOS was then introduced in the third part, and the difficulties of using a quantitative approach was explained. Prior to the interview, an attempt was made to quantitatively evaluate road segments based on the result of the survey, and the difficulties of such an attempt were described. Reflection of the topics in these three parts were the focus in the last part, and the potential and limitations of a quantitative approach was discussed. The interview was semi-structured, and the details of the questions were tailored to the expertise of the planner. The topics brought up in the interview are shown in Table 5. Two planners in Stockholm and one in Amsterdam were interviewed.
Table 5
Interview topics and questions (city planners)
Topic Question
Case study Based on the start/end points indicted in the map, which route do you think the cargo bike user takes? (asked prior to the interview)
Why do you think this route is chosen?
What kind of problems do you think the cargo bike user may face on this route? How surprising were the reasons behind the route choice?
Planning procedure
What is the process of planning for bicycle like? How are roads evaluated?
What are the criteria of evaluation?
BLOS Do you think BLOS is useful for bicycle planning in Stockholm/Amsterdam? Reflection Do you think map making is useful for planning?
What kind of difficulties does map making involve? What kind of planning for cargo bike is ideal for you?
4. Results and Analysis
4.1. Survey
4.1.1. Overall preferences
Importance of each infrastructure element in Stockholm and Amsterdam is ranked based on mean, median, and percentage of high score answers, and shown in Table 6 and Table 7.
Table 6
Ranking of overall preferences in Stockholm
(N=206) Mean Rank Median Rank High score
(8-10) Rank Type 7.20 3 8 1 59.2 2 Width 6.82 7 7 2 44.7 7 Smoothness 6.87 5 7 2 45.1 5 Straightness 5.82 11 6 3 29.6 11 Parking 7.24 2 8 1 51.9 4 Car 7.09 4 8 1 52.4 3 Heavy vehicle 7.65 1 8 1 65.5 1 Bicycle 4.82 15 5 4 13.6 15 Pedestrian 5.92 9 6 3 31.1 10 Speed limit 5.17 14 5 4 24.8 13 Traffic light 5.84 10 6 3 34.5 8 Intersection 6.19 8 7 2 33.5 9 Gap 6.86 6 7 2 45.1 5 Brightness 5.64 12 6 3 28.6 12 Steepness 5.26 13 5 4 23.8 14
Table 7
Ranking of overall preferences in Amsterdam
(N=121) Mean Rank Median Rank High score (8-10) Rank Type 6.64 5 7 4 46.3 5 Width 6.52 6 7 4 40.5 6 Smoothness 7.08 2 8 1 51.2 2 Straightness 4.84 14 5 12 16.6 13 Parking 5.83 10 6 8 34.7 9 Car 6.79 3 7 4 47 4 Heavy vehicle 7.38 1 8 1 56.2 1 Bicycle 5.23 11 6 8 13.2 14 Pedestrian 5.16 12 5 12 19 12 Speed limit 5.14 13 5 12 28.1 11 Traffic light 6.66 4 8 1 50.4 3 Intersection 6.45 7 7 4 38.9 7 Brightness 5.98 8 6 8 33.9 10 Steepness 5.94 9 6 8 37.1 8
Regardless of the method used, five most important infrastructure elements are the same for each city, even though there are differences in the exact ranking. Traffic volume of heavy vehicles is the most important element in both cities. The result on the one hand suggests that the method used here (survey with Likert scale) can produce informative results in terms of which infrastructure elements generally have high importance without a detailed consideration of statistical operations. On the other hand, it also shows that evaluation of cycling suitability through quantification of infrastructure qualities necessitates a careful selection of statistical measurement if the order had to be strictly analyzed.
In both cities, type of infrastructure, smoothness, traffic volume of cars, and traffic volume of heavy vehicles are among the five most important elements. Existence of car parking in Stockholm and number of traffic lights in Amsterdam are considered important, but they are ranked low in the other city. All other elements have similar ranking in both cities, and significant difference between the two cities can be observed only for these elements.
Table 8
Preferences on type of infrastructure
One-way bike path
Two-way bike path
Bike lane Shared with cars Shared with pedestrians Stockholm Mean 1.45 1.95 2.95 3.93 4.13 Median 1 2 3 4 4 Amsterdam Mean 1.77 1.95 2.81 3.94 Median 1 2 3 4
Table 8 shows preferences on the type of infrastructure, which was measured with Likert scale with five alternatives from very favorable to very unfavorable. “1” represents “very favorable” and “5” represents “very unfavorable”. Mean is not statistically suitable in this case, but is included in Table 8 as a reference. The result supports the common statement that cyclists value physical separation of
cycling space from automobiles (Caulfield, Brick, & McCarthy, 2012; Hull, & O’Holleran, 2014), and the higher the level of separation is, the more preferred the cycling space is.
4.1.2. Group differences
Group differences in the two cities are shown below. Only the evaluation items for which significant difference (Sig. < 0.05) between the two groups are found are shown. Those with higher significance level (Sig < 0.01) are shown in bold.
Differences between two-wheel cargo bike users and three-wheel cargo bike users (Table 9) are especially large for infrastructure elements and width of cycling space. Most of the evaluation items are considered more important by three-wheel cargo bike users, implying that they experience more constraints than two-wheel cargo bike users do. Traffic volume of pedestrians is more important for two-wheel cargo bike users and they favor roads shared with cars in Stockholm, and this may be because bike messengers often use a two-wheel cargo bike that is faster, and speed is important for them.
Table 9
Group difference (two-wheel and three-wheel)
Evaluation item
Group for/by which the item is more important/favored
Stockholm Amsterdam
Type three-wheel
Width three-wheel three-wheel
Parking three-wheel
Heavy vehicle three-wheel three-wheel
Pedestrian two-wheel
Speed limit three-wheel
Steepness three-wheel
Width of two-way path three-wheel three-wheel
Width of lane three-wheel
Shared road (favored) two-wheel
Frequent and non-frequent commuters (Table 10) did not show much difference, but in both cities steepness is cared less by the frequent commuters. A possible explanation is that commuters carry less weight than those who carry children or goods, and prioritize shortness over other route characteristics (Broach, Dill, & Gliebe, 2012).
Table 10
Group difference (commuting)
Evaluation item
Group for/by which the item is more important/favored
Stockholm Amsterdam
Steepness infrequent users infrequent users
Speed limit on shared road frequent users
One-way path (favored) frequent users
Group differences for those carrying goods for private purposes frequently and infrequently show clear differences in the two cities (Table 11). While in Stockholm no significant differences are found for infrastructure elements and the type of preferred infrastructure, there are two items that are more important for frequent users. In Amsterdam, three infrastructure elements (straightness, traffic volume of bicycles and pedestrians) are found to be more important for infrequent users.
Table 11
Group differences (carrying goods for private purposes)
Evaluation item
Group for/by which the item is more important/favored
Stockholm Amsterdam
Straightness infrequent users
Bicycle infrequent users
Pedestrian infrequent users
Width of road shared with pedestrians
frequent users Speed limit on shared road frequent users
Shared road (favored) frequent users
Differences between those who carry goods for work frequently and those who do infrequently (Table 12) are bigger in Stockholm. In Amsterdam, only the smoothness of cycling space is more important for frequent users. Cycling facilities in Amsterdam are often made of blocks that become uneven with time and streets in the city center are often made of bricks, while there are also many cycling paths that are paved smoothly. This high contrast in Amsterdam may be a reason for the group difference. Width of bike paths is generally more important for frequent users, and this seems to be because of the necessity to overtake slower cyclists to ensure timely delivery of goods. In Stockholm type of infrastructure is less important for frequent users, and this could be explained by the fact that a cyclist can choose to share a road with cars even with the presence of dedicated cycling infrastructure.
Table 12
Group differences (carrying goods for work)
Evaluation item
Group for/by which the item is more important/favored
Stockholm Amsterdam
Type infrequent users
Smoothness frequent users frequent users
Straightness frequent users
Pedestrian frequent users
Steepness frequent users
Width of one-way path frequent users frequent users
Width of two-way path frequent users
Favors shared road frequent users Favors road shared with
pedestrians
infrequent users
Whether or not carrying children frequently (Table 13) seems to be a factor influencing the route choice preferences greatly in Stockholm, but only slightly in Amsterdam. Those who carry children frequently in Stockholm care more about the type of cycling space and speed limit, but not in Amsterdam. Frequent uses in Amsterdam consider brightness of the streets important, and whether this is due to infrastructure or safety from crimes is unclear.
Table 13
Group differences (carrying children)
Evaluation item
Group for which the item is more important/favored
Stockholm Amsterdam
Type frequent users
Car frequent users
Pedestrian infrequent users
Speed limit frequent users
Brightness frequent users
Width of lane frequent users
Speed limit for lane frequent users Speed limit for shared road frequent users Favors one-way path frequent users Favors road shared with
pedestrians
frequent users
Patterns in the two cities are different, and it is difficult to generalize differences in route choice preferences based on the type of cargo bike or purpose of usage. There are only five evaluation items with the same result in both of the cities. Three-wheel cargo bike users care more about the width of cycling space, traffic volume of heavy vehicles, and width of two-way cycling path. Because three-wheel cargo bikes are wider than two-three-wheel cargo bikes, this tendency to care more about width seems reasonable. Frequent commuters care less about steepness. Frequent carrier of goods for work care more about smoothness of cycling space and width of one-way path. The only item for which strong difference (Sig < 0.01) is found in both cities is the width of cycling space between two-wheel and three-wheel cargo bike users, implying that width of cycling space is outstandingly important for three-wheel cargo bike users.
Group differences in speed limit is not observed for Amsterdam in any groupings. This can be due to the common practice to completely separate cyclists from motor vehicles with a higher speed limit and to enforce a low speed limit (usually 30km/h) on residential streets, while in Stockholm residential roads can have a higher speed limit (50km/h).
Some differences can be observed in terms of traffic lights at an intersection (Appendix B.2.6). In both cities, more three-wheel cargo bike users and those carrying children frequently prefer signalized intersections, possibly because it is harder to move quickly with a three-wheel cargo bike and they are often used for carrying children. On the other hand, those carrying goods professionally tend to dislike signalized intersections, presumably because it is important to deliver goods on time. In all of the groups, percentage of those who are neutral about intersection control is lower in Amsterdam. It is however difficult to say whether this is due to city context differences or other factors such as cultural differences.
The validity of group difference analysis is limited by the definition of grouping method. For each purpose of usage, those who use a cargo bike two or more days a week were categorized as frequent users. This information does not reveal the amount of usage for this purpose among other purposes, and can produce misleading results. For example, a person who uses a cargo bike to carry children every day and to carry goods for work twice a day falls into “frequent users to carry goods for work”, even though the answers may be based mostly on the preferences while transporting children. Another person who uses a cargo bike only once a week and only for the purpose of carrying goods for work is categorized as “infrequent users to carry goods for work”, in which case the answers are
solely based on the usage of carrying goods for work. The difficulty to control the usage purpose based on the usage information leads to potential errors in the statistical results.
4.2. Interview (cargo bike user)
Seven people were interviewed in Stockholm. Reasons for choosing a certain route include time, distance, scenery, safety and infrastructure. Many of the interviewees were still not happy with their chosen route, mainly complaining about car traffic and infrastructure quality. While car traffic was mentioned as a safety issue by parents carrying children, many interviewees also pointed out that with a cargo bike that is larger than a normal bike, it is often impossible to overtake cars waiting in traffic and they end up staying behind cars. Several people stated that bike paths with physical separation can be an issue for a wide cargo bike with high volume of bike traffic or an obstacle, and some prefer bike lanes. Unclarity of where to cycle, inconsistency of infrastructure, rough surface, gaps at infrastructure transition, hills, and bicycle traffic were also mentioned.
There were some conflicting preferences in terms of infrastructure type and traffic lights. One section of Fleminggatan, a main street in the city, has a bus lane shared with bicycles. One respondent mentioned it as an example of worst road segment because carrying children on a cargo bike while sharing a road with buses is scary, but another interviewee called it the best segment because there is a lot of space thanks to the bus lane. Another opinion conflict was seen for green wave, a row of green lights made by signal timing control to allow cyclists to bike through consecutive intersections without stopping. For one interviewee whose cargo bike does not have a motor, the speed of green wave is almost too fast, while it was mentioned as a favorable system by another interviewee who uses a cargo bike with a motor.
An example of route choice between two spots, home and a kindergarten, is provided by one interviewee, a father who carries children on a trailer attached to a road bike. Even though the total distance is only about 1km, there are several route options. The blue route goes through woods and is comfortable to bike on, but it is longer, and he takes this route only when he has enough time. The orange line represents a cycling path in the middle of a main road (Valhallavägen), which is mostly completely separated from car traffic with grass and trees on both sides. However, one section of this route indicated with red functions as a parking for cars, and cyclists go through the middle of parked cars. With the low visibility during the evening, he tries to avoid the route while transporting children. The pink route is a bike path along a main road and is the shortest option of all, but the road has a lot of traffic and is not pleasant to cycle along, so this route is only used when he is in a hurry. Another option is to use sidewalks, indicated with green. This is technically illegal and can take longer when there are pedestrians, but is a safe option without the need to make a long detour. Whether he uses the sidewalk on the northern side or southern side depends on the timing of traffic lights.
Fig. 1. Route choice example in Stockholm
In Amsterdam, four cargo bike users were interviewed. Traffic lights and traffic situation were mentioned in three of the interviews as reasons for their route choice. Crossing of a main road that is conceived as dangerous, and crowdedness of a bike parking at the destination were also noted. Bridges are also problematic for some people. Three interviewees mentioned blockage of road, whether on a bike path or a shared road, by construction and motorvehicles, especially delivery trucks. One said that he cannot overtake bike taxis that are significantly wide. Being unable to move quickly and make sharp turns gives the cargo bike user less opportunity to move around cars in case the road is shared, and less comfort in cycling on a main road (van Woustraat) that is shared with cars. Poles at the entrance of a bike path to prevent cars from entering can be irritating, even though there is no problem passing through the poles. Speed bumps and rough surface were also noted as problematic for carrying fragile cargo. While physical separation of cycling space can be appreciated by some, existence of parked cars or bike parking along a path as well as high volume of cyclist traffic or cyclists behaving illegally (e.g. cycling wrong way) can reduce the effective space. People generally appreciate the infrastructure of Amsterdam and most part of the city is accessible by a cargo bike, and many problems they face and complaints they have are not necessarily due to the usage of cargo bike. Such problems and complaints include traffic lights, tourists, and confusing and irritating design of roundabouts and intersections. One stated that because of the Amsterdam’s policy to close down streets for cars, pedestrians are not staying on the sidewalk anymore, making cycling more difficult. An example of a route in Amsterdam is shown below in Fig. 2. The cyclist uses a traditional large cargo bike with three wheels. The black line indicates the route taken, and colored lines are the segments he tries to avoid. The green segment is the official route to the park for bicycles, but because there are many pedestrians, traveling on this segment with his large cargo bike is difficult and instead he uses a path officially made for pedestrians. The orange segment has no dedicated cycling
infrastructure, and with many cars parked on the road, it is not ideal. The red section has a separated path, but the surface is not smooth due to tree routes, and he prefers not to use this route especially with fragile cargo. The last part of his trip requires him to stay on the right side of the road and make two left turns as indicated in blue, but he prefers to avoid the detour and stay on the left side, as the traffic volume of bicycles is low and it is usually not a problem.
Fig. 2. Route choice example in Amsterdam
4.3. Interview (city planner)
Two planners in Stockholm and one in Amsterdam were interviewed. In Stockholm, the route shown in Fig. 1 was used as an example. Guessing the route taken by the cyclist was difficult because there were several options and some parts of the routes involved usage of private roads or illegal usage of roads such as cycling on the sidewalk. The main problem that the cyclist faces, that the segment of a bike path also used as a car parking is not comfortable to cycle on especially in the evening, was not pointed out without a hint. This exercise worked as a lesson that all kinds of bicycles need to be considered in the planning process. Road evaluation for cyclists in Stockholm is done based on several factors such as traffic volume of bicycles, category of roads (commuting route, main route, local route), and safety of cyclists. However, safety is difficult to measure, and there is no clear-cut way to holistically evaluate roads. Maps are actively used in the planning process, and the idea of BLOS was favored by both of the planners as a straightforward way to evaluate roads and provide information to planning. While both agree that map making is useful in planning, technical difficulties such as coordination with other departments and making changes were pointed out.
The interview in Amsterdam started with an exercise using the route shown in Fig. 2. While the western side of the route was not familiar to the city planner interviewed, the route and the reasoning behind it was not surprising to him. He considers route choice of a cargo bike less complex than that
of a normal bike because the cyclist is likely to avoid smaller roads due to its larger size. In Amsterdam, evaluation of roads involves the width of the cycle paths, with a goal of certain percentage of roads equipped with a wide (more than 2.5 meters) cycling space. Speed of cycling is also monitored. There are also surveys about the level of satisfaction for cycling, with both general and specific questions. The interviewee calls a cyclist “a pedestrian with wheels”, and because the usage of bicycle in the Netherlands is different from that in other countries, he does not think BLOS would be useful at all in the Netherlands. He also points out that even if a BLOS map can be made, the map can lose its meaning because combining different criteria makes it difficult to see what the map is about. A large part of infrastructure improvement in Amsterdam depends on public opinions through complaints and suggestions, and the city takes a more qualitative approach to improve infrastructure.
5. Conclusion
In this research, a survey was used to first explore the general preferences of cargo bike users. In both cities, four of the five most important infrastructure elements were the same: type of infrastructure, width of cycling space, traffic volume of heavy vehicles, and traffic volume of cars. Analyses of group differences show that even though the type of cargo bike and the purpose of usage influence the cyclists’ preferences in each city, it is difficult to generalize these preferences without considering the local context differences. The survey shows two overarching results: traffic volume of heavy vehicle is the most important factor, and width of cycling space is significantly more important for three-wheel cargo bikes. According to the interviews, the reasons behind the former finding are different in the two cities. In Stockholm, people often raised concerns about safety of cycling with heavy vehicles. In Amsterdam, on the contrary, interviewees often mentioned difficulty of passing parked large vehicles. Streets in Amsterdam are much narrower than those in Stockholm, and cargo bike users need to take into account the possibility to get stuck around a parked vehicle. Physical separation of cycling space from motor vehicles has been a main topic of planning for cycling (Caulfield, Brick, & McCarthy, 2012; Hull, & O’Holleran, 2014) and the result in Table 8 supports this preference, but interviews reveal that some people like to share a bus lane with buses because of its wide space. This preference for the combination of high traffic volume of heavy vehicles and no dedicated space for cycling could not be predicted only through the survey. Difficulty of being flexible with a cargo bike, that in case of an obstacle on a physically separated path the cyclist may have to go back because it is difficult to go off the physical separation due to its heavy weight, is one thing that needs to be considered before the physical separation of cycling space is implemented. Thus, having enough width is a key element for convenience and safety for three-wheel cargo bike users.
Interviews also revealed that route choice of cargo bike users is a complex process that involves many considerations that cannot be easily quantified and used in a model such as BLOS, which was merely adjusted from a model to predict the route choice of motor vehicles. Even if quantification of infrastructure quality is possible, there are factors that are still difficult to measure or embed in a model such as pleasantness, darkness, time that the cyclist has, the timing of traffic lights, and the direction of travel, as can be seen in the examples of route choice. Type of cargo bike and purpose of usage have been proven to influence route choice preferences, and both the survey and interviews suggest that differences vary depending on the city. Despite the goal of tools such as BLOS, namely generalizing route choice preferences or cycling suitability, the results suggest that there is no simple way for generalization. While statistical and study design imperfection can contribute to the different patterns in each city to a certain extent, no reason was found to believe that route choice preferences of cargo bike users are universal. As the planner in Amsterdam states about cyclists in Amsterdam, that they are pedestrians with wheels, cargo bike users also do not fall in the conventional understanding of “cyclists”, due to their varying styles and purposes.
These results suggest that planning of cycling infrastructure for cargo bikes requires a study tailored to the local context, and preferably a combination of a quantitative approach, which is capable of showing the “what” aspect of a phenomenon, and a qualitative approach, which can reveal the “why” aspect of it. The extent to which this statement is applicable to normal bikes cannot be judged directly from this study, but it suggests that varying preferences of cyclists make it difficult for planners to provide infrastructure that is favored by everyone. With the complexity and varying preferences of route choice for cargo bikes, an attempt to improve cycling environment for normal bicycles could counteract the intention for cargo bikes, and additional considerations should be made for the safety and comfort of cargo bike users. With more and more innovative unconventional types of bicycles (and other vehicles using cycling infrastructure) appearing on streets, there is an increasing need for inclusive planning of cycling infrastructure. The proposed planning strategy of focusing on both “what” and “why” can be beneficial not only for cargo bikes but also for a wider range of cycling infrastructure users.
5.2. Limitations and discussion
Selection method of survey participants may have resulted in biased results in terms of some infrastructure preferences. In Stockholm, many of the participants were referred to this research on streets with a high volume of bicycles, therefore main roads. This may have resulted in overrepresentation of those who prefer to cycle on main roads, which tend to have particular infrastructure qualities such as separated bike path and high traffic volume of cyclists. More focus was put on commuting hours, and those who are only cycling during the off-peak hours may have been underrepresented. In Amsterdam, much of the participant collection was done at primary schools due to high usage of cargo bikes among parents with young children, and this should be taken into account in the share of purpose of cargo bike usage.
This research did not include a systematic comparison between cargo bikes and normal bikes, and the extent to which the route choice preferences observed in this research are determined by the usage of cargo bike is unknown. Even though the differences between normal bikes and cargo bikes were asked in the interviews, a focus on them in the survey could have provided a more objectively comparative result, and different interpretations may have been made. This is not a major issue academically because the differences between them is not the direct focus of the research, but such data could be collected in the future studies to increase the usefulness of the research to inform planning. One of the planners interviewed in Stockholm said that this is the kind of research that the city needs to conduct because they do not know what cargo bike users want. Knowledge of differences between normal bikes and cargo bikes can then be applied to the planning process, which currently is focused mostly on normal bikes even in Amsterdam, where usage of cargo bikes is very common. More and more types of unconventional bikes are appearing these days, and inclusiveness seems to be an important element for planning for bicycles.
Engineers are developing new technologies to cope with complex human decision making. Will there be a day when they can finally predict our route choice even for cargo bike users? Is the black box of route choice, our brain, still going to be too complex to be modelled?
6. Acknowledgement
Special thanks should be sent to Professor Marco te Brömmelstroet for supervising the research with ample feedback, Professor Luca Bertolini as a second reader, Urban Cycling Institute at University of Amsterdam for supporting the research, and Graduate School of Social Sciences at University of Amsterdam for sponsoring the research. The author also appreciates help of those who helped with
distribution of the survey: Ronin in Stockholm, and Dr. Byke, Urban Arrow, Henry (WorkCycles), and Fietsersbond in Amsterdam.
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