Article
citation information:
Rahman, F.I. Analysing the factor influencing
travel pattern and mode choice based on household interview survey data: a case
study of Dhaka city, Bangladesh. Scientific
Journal of Silesian University of Technology. Series Transport. 2020, 109, 153-162.
ISSN: 0209-3324. DOI: https://doi.org/10.20858/sjsutst.2020.109.14.
Faysal Ibna RAHMAN[1]
ANALYSING THE FACTOR
INFLUENCING TRAVEL PATTERN AND MODE CHOICE BASED ON HOUSEHOLD INTERVIEW SURVEY
DATA: A CASE STUDY OF DHAKA CITY, BANGLADESH
Summary. For transport planning
and policy-making, visualising the relationship among attributes; gender,
education, occupation, age with travel pattern and mode choice is important.
Household Interview Survey (HIS) is one of the major inputs in transport study
which contains information about travel and demographic characteristics. From
the analysis of 28,235 households in Dhaka city, this study represents the social
demographic characteristic of Dhaka city based on the household survey. It
was found that 89.79% of dwellers make double trips in a day and the trip
rate per trip maker is 2.16, where 14% of total trips are generated at morning
peak time between 7 to 8 am. The bus is the most preferable mode share and its
contribution is about 35%. The scenario changed in a multimodal trip case and
walking was the domination mode share with about 45% of total trips. Vehicle
ownership had a vital rule in particular mode choice, especially in car and
motorcycle household ownership case. Significant impact on travel patterns and
mode choice criteria was found with gender, education, occupation, age,
household income, trip purpose and time and vehicle ownership, which can help
to formulate the strategic plan to solve the transport-related problem in
Dhaka.
Keywords: attribute, mode choice, travel pattern
1. INTRODUCTION
Investigation
of the travel pattern mode choice is a vital research topic in transportation
research and urban planning, irrespective of developed and developing
countries. It offers the background information required to better understand
the complex relationship among urban structure, transportation system and
people’s activity participation [1,2]. The demand for travel is derived
from the demand for spatially separated activities of people. Travel behaviour
largely depends on a number of factors such as travellers personal/household
attributes, socioeconomic characteristics, the purpose of trips, the place of
origin-destination, pace of economic growth, local culture and the medium of
transport under the constraints of time, cost, comfort, availability, etc. It
is very important to analyse the relationships among these factors to be able
to grasp current and future travel patterns as well as travel demand. The
growing volume and complexity of urban travel in developing countries have
become a major concern to transportation planners, service sponsors in urban
area and policy makers [3-6]. People travel because they get benefits from it, or more precisely, they
get benefits from the things they do or buy at the end of the trip [7]. One of
the key issues of travel behaviour is the travel mode choice decision. Mode
choice plays a vital role in transportation planning and policy making in any
city. Past research has clearly shown that individual and household
socio-economic characteristics have a strong influence on mode choice
decisions. They identified income, gender, vehicle ownership, and employment
status as the most influencing variables in mode choice decisions [8,9]. In
most cases, a large-scale Household Interview Survey (HIS) is conducted to
understand passenger movement or build the four-step travel demand forecasting
model. This type of household survey has played a significant rule in
addressing the urban transportation problem of cities and provide a valuable
source of information for transportation planning.
With over 18 million population, Dhaka
is one of the world’s largest and most densely populated cities, which
faces acute transportation-related problems due to unplanned urbanisation and
inadequate road network with an increasing number of private and public
transport. Travel activity has a deep connection with personal attributes such
as age, income, sex, occupation and household car ownership. Household
interview survey on Dhaka city which was conducted by the Bangladesh Bridge
Authority in 2019 is used in this study to understand the travel pattern of
Dhaka city dwellers and make relationships among travel-related parameters to
personal/household attributes. This study can help in policy-making and traffic
management to reduce traffic jams as well as to take a new transport-related
project.
Although Dhaka is a very old city, few
detailed household interview surveys have ever been conducted for transport
planning studies, however, none have effectively achieved the basic objective
of the transportation system. The first household survey was conducted for the
Greater Dhaka Metropolitan Area Integrated Transport Study [10]. For the
Strategic Transport Plan for Dhaka [11] and Revision and updating of the
strategic transportation plan for Dhaka [12] project, a household survey was
also conducted. But all of those studies cannot visualise detailed travel
behaviour and mode choice factors of Dhaka city dwellers which are related to
personal or household attributes. There were some limitations of these studies.
As such these studies only consider single-mode trip for mode choice analysis
and do not consider a multimodal trip in mode choice analysis. Household
car/motorcycle/bicycle ownership were not considered in mode choice analysis.
Trip frequency per person along with the number of mode interchange during a
single trip was analysed. Subsequently, this study was done to overcome the
previous studies and capture detailed information about the travel behaviour of
city dwellers.
2.
OBJECTIVES
The objective of this study is to compute the basic
features of the surveys-question items. This will help in conducting similar
HIS in the future, along with the purpose to clarify the relationship of the
city’s economic performance, transportation situations, cultural
background and mode share using travel behaviour analysis or statistical
models.
3. DATA
Household interview survey is a major
input to transport planning studies that gather information on travel and
socio-economic characteristic of the population. This survey was conducted across the
Dhaka Metropolitan Region to gather data on travel patterns, mode choice
origin-destination and other characteristics of trip makers in the first half
of 2019. The survey was conducted on 28,235 households, which consists of
111,662 household members considering 146 Traffic Analysis Zone (TAZ). The TAZ
area helps to capture accurate travel behaviour throughout the city. Fig. 1
shows the TAZ area of Dhaka city.
Fig. 1. Traffic Analysis Zone (TAZ) in
Dhaka city
4. SOCIAL
DEMOGRAPHIC INFORMATION OF DHAKA CITY
The scenario of social demographic
information of Dhaka city can be observed from the household interview survey.
There is a significant relationship between social-demographic attributes with
travel behaviour attributes. For an understanding of the travel behaviour of
city dwellers, it is important to visualise the social demographic information
of the city. The survey was conducted on 28,235 households, which consists of
111,662 household members. Among them, 58,090 (52.02%) household members were
male and 53,572 (47.98%) household members were female. From the analysis, it
was found that 3.95 people live together per household. Fig. 2 represents the
percentage of the male and female number of the survey as well as the present
scenario of Dhaka city male and female population ratio.
Fig. 2. Percentage of the male and
female population of Dhaka city
The Occupation of Dhaka city dwellers
was included in this survey. Ten criteria of occupation: student, public
employee, private employee, business, agriculture, housewife, unemployed,
retired, not applicable and others. People below the age of 6 years were
considered under the not applicable criteria. Fig. 3 represents the percentage
of occupation of Dhaka city dwellers. Student and housewife occupations capture
a large percentage, 26.66 and 25.46%, respectively. It is indicated that 2.80,
16.10 and 12.76% of the people are public employees, private employees, and
business people. It is remarkable to note that only 1.56% of the people are
unemployed.
Fig. 3. Percentage of the population
belongs to different occupation criteria
Fig. 4 shows the percentage of
education qualification level criteria of Dhaka city dwellers. It was observed
that the number of the percentage population decreased with an inverse increase
in the educational qualification level. From the analysis, it was discovered
that about 15% of people have graduated level education qualification.
Fig. 4. Percentage of different
educational qualification criteria of the population
Household income level is a vital
parameter to understand the lifestyle and financial status of the city. Fig. 5
represents the percentage of different household income level criteria of the
population. It was found that majority of the people belong to 20,000 to 30,000
BDT household income level criteria and 22.97% of the people belong to 30,000
to 40,000 BDT household income level criteria.
Fig. 5. Percentage of different
household income level criteria of the population
The percentage of the different age
level criteria in the population is shown in Fig. 6. Most of the people belong
to the 21 to 30 age limit which is 22.11% of the population. Only about 3.50%
of the people were above 60 years.
From this survey, it is indicated that
49.54% are trip makers on a particular survey day. And 39.85 and 10.62% are not
trip makers and not applicable, respectively, in this survey. Tab. 1 shows the
percentage of trip makers in this survey.
Fig. 6. Percentage of the different age
level criteria of the population
Tab. 1
Percentage of trip makers in the
survey
|
Trip maker |
Number |
Percentage (%) |
|
Yes |
55,315 |
49.54 |
|
No |
44,494 |
39.85 |
|
Not applicable (<6 year) |
11,853 |
10.62 |
|
Total |
111,662 |
100.00 |
5.
TRIP CHARACTERISTICS
Household interview survey data
consists of household data, individual data, and trip data. The rate of trips
per trip maker is 2.16, while the rate of trips per household is 4.20.
Characteristic of trip generation is influenced by different factors such as
sex, income, education, occupation, time and purpose. It is important to
understand the proper transportation-related policy. This section represents
the variation of trip generation attributes considering social demographic
factors.
Fig. 7. Percentage of trip generation
by gender
Fig. 7 represents the gender
characteristics of travellers analysed against the number of trips. Males are
mostly responsible for trip generation in Dhaka city. 89.78% of the people of
Dhaka city make double trips per day. Trip frequency per person per day is
shown in Fig. 8.
Fig. 8. Percentage of travellers
according to the number of trips
Fig. 9 shows the proportion of trips
and their departure times. The morning peak in Dhaka is quite pronounced, with
about 14% of all trips generated around 7 to 8 AM.
Fig. 9. Percentage of trip generation
time
In the case of trip purpose, 56.05,
26.72, 7.19, 4.09 and 3.57% trips were generated for work, education, personal
issues, shopping and leisure purpose from home. On the other hand, the house is
the dominating trip destination place or trip purpose from trip origin
excluding home place. Tab. 2 represents the trip percentage according to the
trip purpose. And Tab. 3 visualised the trip categories according to home base
and non-home base trip. 97% of all the trips have linkage with the home for its
start end or its end and it is really high compared to other cities.
Tab. 2
Percentage of trip generation from
origin according to purpose
|
Origin/
Destination |
Home |
Work |
Education |
Shopping |
Medical |
Personal
issues |
Leisure |
Other |
Total |
|
Home |
0.02 |
56.05 |
26.72 |
4.09 |
1.91 |
7.19 |
3.57 |
0.44 |
100 |
|
Workplace |
92.34 |
5.75 |
0.07 |
0.50 |
0.09 |
1.10 |
0.07 |
0.09 |
100 |
|
Education |
98.61 |
0.38 |
0.14 |
0.21 |
0.01 |
0.49 |
0.10 |
0.05 |
100 |
|
Shopping |
96.77 |
0.76 |
0.04 |
0.65 |
0.15 |
1.26 |
0.27 |
0.11 |
100 |
|
Medical |
95.89 |
0.86 |
0.00 |
0.94 |
0.34 |
1.63 |
0.09 |
0.26 |
100 |
|
Personal issues |
94.35 |
1.41 |
0.17 |
0.86 |
0.34 |
2.26 |
0.30 |
0.32 |
100 |
|
Leisure |
96.99 |
1.70 |
0.00 |
0.28 |
0.14 |
0.52 |
0.28 |
0.09 |
100 |
|
Others |
90.68 |
5.14 |
0.64 |
0.32 |
0.32 |
1.61 |
0.32 |
0.96 |
100 |
Tab. 3
Percentage of trip base on home base
and non-home base trips
|
Type of trip |
Percentage of trip (%) |
|
Home base trip |
97.188 |
|
Non-home base trip |
2.8112 |
Although student and housewife
occupations capture the large percentage of the population in the city, the
private employee is the major occupation responsible for 29.45% of trips. Fig.
10 shows the distribution (in percentage) of trips by occupation. The
relationship between trip and education is shown in Fig. 11.
Fig. 10. Percentage of trip generation
by occupation level
Household income represents its
ability to pay for a trip and the number of trips generated by a household. A
general trend is that the higher the income, the higher the trip generation
rate. Figs. 12 and 13 visualise the distribution of trips according to
household income level and age level, respectively. Household income level
directly represents the personal income level. From the analysis, it was
discovered that household income levels 20,000 to 30,000 and 30,000 to 40,000
are most responsible for trip production. With the increase in household income,
trips per person increased along with the majority of the trips generated by 21
to 30 and 31 to 40 age level people.
Fig. 11. Percentage of trip generation
by education qualification
Fig. 12. Percentage of trip generation
by household income level
Fig. 13. Percentage of trip generation
by age
6.
MODE CHOICE ANALYSIS
The issue of mode choice, therefore,
is probably the single most important element in transport planning and policy
making. It affects the general efficiency with which city dwellers can travel
in urban areas. Therefore, it is important to develop and use a model that is
sensitive to the attributes of travel that influence the individual choice of
mode. Characteristics of the trip maker, characteristics of travel and
characteristics of transport facility are the three major components to
influence mode choice. This section will represent the relationship between the
trip maker and the mode. All available ten types of mode are considered in the
household survey. In Dhaka, train and water vehicles are not available as modes
of transport.
Fig. 14. Percentage of mode share
considering the trip number
Fig. 15. Percentage of gender category
considering different modes
Fig. 14 shows the main mode share
during the trips of Dhaka city dwellers. Bus trips are the biggest in Dhaka,
about 35% of trips are governed by bus. Walking and rickshaw are second and
third dominating mode choice. For short travel distance, the rickshaw is used
by dwellers. Although most of the road space is blocked by cars, they occupied
less than 5% of the total trip to Dhaka city. With the increase of the
ridesharing system and for the avoidance of traffic congestion, people are
interested in using the motorcycle and the mode share of the motorcycle has had
increasing complains in the last few years. Mode choice of auto-rickshaw/CNG and
utility/laguna/tempu is lower than the bus and those modes are preferred for
short to medium travel distance. Dhaka is not designed for a dedicated lane for
bicycles, hence, the percentage of mode share of the bicycle is comparatively
low. Dhaka has only one rail line for intercity service with the absence of an
urban rail service. In this case, the opportunity for using the train is
approximately low for city people. And water vehicle is only available in the
old Dhaka area. Moreover, mode share is not so high considering the urban area
of Dhaka.
Gender is one of the key factors for
mode choice. Figs.15 and 16 show the mode choice by gender. Females prefer
walking and rickshaw rather than other modes. The bus is the domination mode
preference for males along with bicycles, motorcycles are only preferable by
males.
Fig. 16. Percentage of mode share
considering gender
Fig. 17. Percentage of education level
considering different modes
Figs. 17 and 18 represents the mode
choice by education level. Mode preference for walking and rickshaw is
gradually decreased with the increase of education qualification level. The
major share of car and motorcycle trips are performed by the graduation
qualification (BA and MA) people. But the car is more shared by MA than BA
education level. The bus is the major mode share for all education
qualification people. Walking is the most dominant mode share for below primary
level and six to ten class people. Furthermore, it is also noted that walking
is also a major share for the madrasha student people.
Fig. 18. Percentage of mode share
considering education levels
Fig. 19. Percentage of occupation
considering different modes
The choice of mode diversifies with
the variation of occupation. Figs. 19 and 20 represent the mode choice by
occupation. The majority of mode share is captured by private employees and the
bus is the main mode for the private employee. Walking and rickshaw are the
domination mode for students because the majority of trips were performed
within short distance. 50% mode share of bicycle is occupied by private
employee people. Not applicable part was only captured by the less than
six-year age people and out of the list which is not so common are included in
others.
Fig. 20. Percentage of mode share
considering by occupation
Household income has a strong impact
on mode choice. Higher-income households and persons are thought to place a
higher value on the comfort and convenience associated with private auto. Figs.
21 and 22 indicate the mode choice by household income level. With the increase
in household income, the percentage of mode share of walking gradually
decreased. On the other hand, the percentage of car and motorcycle mode share
gradually rose with the increase in household income. About 65% of users of car belongs to
greater than 60,000 BDT household income.
Fig. 21. Percentage of household
income level considering different modes
Fig. 22. Percentage of mode share
considering household income levels
Figs. 23 and 24 represents the mode
share scenario by age. Car is a preference for the oldest people and preference
gradually increases with the increase of age for safety. Middle-aged people
usually prefer the bus, rickshaw, and walking mostly for their trips.
Fig. 23. Percentage of age considering
different modes
Figs. 25 and 26 show the mode share by
purpose. The purpose is a significant issue for mode choice. Home and work are
the two major purpose of all trips. Work and home purpose capture about 80 to
90% trip share for all modes. People prefer cars for personal issues and
leisure rather than for work trips. Walking is not preferable for medical
purpose.
Fig. 24. Percentage of mode share
considering age
Fig. 25. Percentage of purpose
considering different modes
Fig. 26. Percentage of mode share
considering purposes
Figs. 27 and 28 show the mode share by
trip generation time. Most of the trips for all modes were generated during the
morning peak between 7 to 9 AM. There is another peak time found in the evening
peak at 5 PM for all modes. But the percentage of share of the evening peak is
almost half of the morning peak for all modes.
Fig. 27. Percentage of departure time
considering different modes
Fig. 28. Percentage of mode share
considering departure times
7.
MULTIMODAL TRIP CHARACTERISTIC
Multimodal trip making, that is, trips
using a combination of several modes between origin and destination, is
expected to be beneficial to the society and might offer advantages to the
traveller as well. This may consist of different vehicles, such as a car,
bicycle, bus or different services, such as stop or express services. A
multimodal trip, thus, always consists of two or more legs with different modes
between which a transfer by foot is necessary. Typical examples of multimodal
trips are chains such as walk-bus-bicycle-walk. From the analysis, it was
pointed out that 46.80% of trips of Dhaka city are unimodal trips, which
consist of single-leg on a trip and other trips are multimodal. Walking is the
major mode for single leg trip. Fig. 29 shows the percentage of unimodal and
multimodal trips. 22.78% trips consist of two legs on a single trip and 25.81%
trips consisted of three legs on a single trip.
Fig. 29. Percentage of multimodal trip
Previous
studies have neglected the complete mode share in the multimodal trip, only
analysing the mode share for the main mode on a trip. Without considering the
multimodal trip analysis, it is difficult to understand the complete transport
system. Fig. 30 shows the mode share considering a multimodal trip. It was
found that more than 45% of trips were made by walking, which is one of the
major dominating modal shares in Dhaka. Because the first and last leg of the
trip is performed by walking mode in the majority of multimodal trips.
Fig. 30. Mode share considering
multimodal trip
Fig. 31
shows the comparison of
mode share between the main mode and all mode in the multimodal trip. Except for the mode share of walking, other
modes share were comparatively lower for mode share of multimodal trips than
mode share of main mode in trips.
Fig. 31. Comparison of mode share
between main mode and all modes in multimodal trip
8.
MODE SHARE CHARACTERISTIC OF VEHICLE OWNERSHIP
Fig. 32. Mode share for only household
car ownership
Researchers
have identified that vehicle ownership is a fundamental element in
travel-related decision-making processes in Asian cities [13,14]. This section
will identify mode share for the car/motorcycle or bicycle household ownership.
Dhaka is not well furnished with public transport such as a bus. Recently,
vehicle household ownership significantly increased in the bid to avoid trouble
in public buses.
Car
ownership is regarded as a vital variable in travel pattern and mode choice.
Car ownership has a direct linkage with the income level of a household. Fig.
32 revealed that more than 40% of all trips for car ownership households was
generated by car and Fig. 33 compares the mode share for all household and car
household ownership. It was noted that high-income families have household
cars. Hence, bicycles and other public modes for comfort and safety were not
preferred. It is also indicated that modal share of motorcycle and of car
ownership household is comparatively higher than the general household because
of high income. Percentage of those using walking and rickshaw as a mode is
approximately lower for car ownership household people than other people.
Fig. 33. Comparison of mode share
between all household and car ownership household
Fig. 34
points out that about 35% of all trips for motorcycle ownership households was
generated by the motorcycle and Fig. 35 compares the mode share for all household
and motorcycle household ownership. The mode share of the motorcycle is higher
for those people who belong to the motorcycle ownership household. Moreover, it
was found that the private mode; car and motorcycle is higher than in other
public modes. Mode share of walking and rickshaw are comparatively low for
motorcycle household ownership people.
Fig. 34. Mode share for only household
motorcycle ownership
Fig. 35. Comparison of mode share
between all household and motorcycle (MC)
ownership household
Except for
the mode share of the bicycle, other modes share are comparatively lower for
bicycle ownership than other people. Fig. 36 shows that more than 15% of all
trips for bicycle ownership households was generated by the bicycle and Fig. 37
compares the mode share for all household and bicycle household ownership.
Fig. 36. Mode share for only household
bicycle ownership
Household vehicle ownership represents
a significant factor for mode choice for a household member. Preference for walking,
rickshaw and other public transport modes are approximately low for vehicle
household ownership. Given that Dhaka is not well designed for bicycles, in
this case, the number of bicycle ownership is insignificant. To reduce both
traffic jams and the number of car ownership, policy makers can take a step to
increase bicycle ownership. Additionally, it is necessary for the
eco-transportation system.
Fig. 37. Comparison of mode share
between all household and bicycle ownership household
9. DISCUSSIONAND
CONCLUSION
This paper analysed the travel and
social-demographic characteristics of trip makers of Dhaka city dwellers using
a household interview survey which opens a new avenue for researchers involved
in transportation planning for Dhaka city. Demonstrating the relationship trip
characteristics with age, gender, occupation, education as well as modal share
analysis considering attributes; gender, age, occupation, education, multimodal
and vehicle ownership. This study found out that walking is the domination mode
share for multimodal trips. And the bus is the main mode share for Dhaka.
Walkway in Dhaka is not well established along with a public bus that fails to
provide better service. Policy makers need to be concerned about providing a better
facility in walking and bus priority related project. This will help in
reducing traffic jams, which is one of the major problems in Dhaka city.
Furthermore, this paper described the travel pattern of Dhaka, which will help
in any development project related to transport. However, this analysed data
does not include precise Level of Service (LOS) and trip distance, thus, the
close relationship between travel behaviour with LOS and trip distance should
be examined by future analyses.
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Received 05.08.2020; accepted in revised form 02.11.2020
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Journal of Silesian University of Technology. Series Transport is licensed
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