A Factor Analysis for Bus Choice Based on Structural Equation Modeling – A case study of Ho Chi
Minh City, Vietnam(構造方程式モデリングに基づくバス選択行動の要因分析 – ベトナム・ホーチミン市のケーススタディ)--------------------------------------------------------------------Student: Huynh Thi Kim Ngan
Supervisor: Prof. SANO Kazushi
Urban Transport Engineering and Planning Laboratory
1. Introduction
1.1 Background
In Vietnam, the increased usage of personal vehicles has made huge pressure on transport infrastructure andthe urban environment. How to improve traffic congestion is a challenging question in big cities such as Ho
Chi Minh City (HCMC).

Traffic congestion in HCMC has spread to be a widespread societal concern, which has slowed down
economic activity, increased travel time and expense, and decreased quality of life. To address the issues
with the present transportation system, it is crucial to analyze traffic behavior, customs, and culture.
Additionally, it is vital to create measures to encourage the use of buses and discourage the use of personalautomobiles in HCMC.
1.2 Research Objective
This study aims: (1) To find out the indicators relating to the city bus service in the context of HCMC; (2)To identify the important factors which affect users’ perception and expectation of the city bus service; (3)To identify the relationship between users’ perceptions and overall satisfaction with the service and theirintention to use the bus.
2. Methodology
2.1 Research Framework
The methodical procedure consists of the following four main tasks: 1) Initial work: First, the problem
description was figured out, and then the research objectives were determined; 2) Questionnaire design; 3)
Data analysis and modeling: This section contains four preliminary efforts. First, a survey was utilized tocollect data. After collection, the data were recorded and checked. Thirdly, the reliability test, standard

deviation was tested using descriptive statistics. Finally, the data were analyzed using Exploratory Factor
Analysis (EFA), Confirmatory Factor Analysis (CFA) and Structural Equation Model (SEM); 4) Final work:
This part included an overview of the study's results, the discussion, policy implement and future works.

2.2 Data Collection
Survey area: HCMC’s population is more than 9,1 million people (2021). Data was collected by interviewing.
The individuals who participated in this study were randomly chosen from bus stops and nearby areas ofmany urban districts in HCMC. The sample size is 550 samples.
The questionnaire survey includes 4 parts: Personal data (age, gender, education level, occupation, monthlyincome, vehicle ownership), Travel data (trip purpose, mode, frequency of use, travel distance), passenger’sperception and overall satisfaction, passenger’s expectation and intention to use bus as commuting.
2.3 Data analysis
Descriptive analysis is used to analyze the respondents’ characteristics. EFA and CFA were conducted toidentify the latent variables which are input in SEM. SEM is an effective technique used to explain theconnection between many different factors. It was created using theories that demonstrate the relationships
between unobserved variables and the correlation between unobserved variables and observable variables.
SEM was used in this study to investigate the connection between observed variables as bus’s attributes,
users' perceptions, satisfaction, and intention.
The figured below shows the standard structural equation modeling. Structural Equation can be exemplified
as structural equation (3.1) and measurement equation (3.2)

From the figured, which may be represented as
𝜂(𝑚𝑥1) = 𝐵(𝑚𝑥𝑚) 𝜂𝑚𝑥1 + Γ𝑚𝑥𝑛 𝜉𝑛𝑥1 + 𝜁𝑚𝑥1 … … … … … (3.1)
𝑦𝑝𝑥1 = 𝛬𝑦(𝑝𝑥𝑚) 𝜂𝑚𝑥1 + 𝜀𝑝𝑥1
𝑦𝑞𝑥1 = 𝛬𝑥(𝑞𝑥𝑚) 𝜂𝑚𝑥1 + 𝛿𝑞𝑥1} … … … … … … (3.2)

Where, 𝜂′ = (𝜂1 , 𝜂2 , 𝜂3 … … … 𝜂𝑚 ) and 𝜉 ′ = (𝜉1 , 𝜉2 , … … . . 𝜉𝑛 ) are latent dependent and independent
variables respectively. Similarly, vectors 𝑦 ′ = (𝑦1 , 𝑦2 , … … … … . . 𝑦𝑝 ) and 𝑥 ′ = (𝑥1 , 𝑥2 , … … … … … 𝑥𝑞 ) are
observed as dependent and independent variables respectively. 𝛣(𝑚𝑥𝑚) and 𝛤(𝑚𝑥𝑛) are coefficientmatrices and 𝜁 ′ = (𝜁1 , 𝜁2 , … … 𝜁𝑚 ) is a random vector of residuals. The vectors of errors of measurement iny and x are ε and δ, respectively. The matrices 𝛬𝑦 (𝑝 × 𝑚) and 𝛬𝑥 (𝑞 × 𝑛) are regression matrices of y on ηand of x on ξ, respectively.
2.4 Research Hypothesis
The bus quality service and passengers' perceptions, which are related to satisfaction and bus choice, are themain points of the hypothesis. The comfortable and convenience, time and safety of bus are the aspects ofpassengers' perceptions as shown in the figure below.

3. Result and Discussion
Relationship
Comfortable → Perception
Time→ Perception
Safety→ Perception
Convenience → Perception
Perception→ Satisfaction
Satisfaction→ Intention

St. factor loading
0.326
0.299
0.162
0.118
0.3220.101

P-value
***
***
0.14
0.41
***
0.15

The factors "Comfortable" (Q13-Q17) had five variables, "Safety" (Q18-Q20) had three variables,"Convenience" (Q21-Q24) had four variables, and the factor "Time" had four variables (Q25 – Q28). Using
Exploratory Factor Analysis (EFA), 16 qualitative characteristics of the city bus service were divided into
four categories that most significantly influenced passengers' perceptions: Comfortable, Safety, Convenience,and Time. The second-ordered Confirmatory Factor Analysis (CFA) was employed to assess whether thefactor structure was sufficient.
The result show that Comfortable has a substantial role, followed by Time, Safety, and Convenience, in thatorder. According to the result, there was a little statistically significant association between satisfaction andintention as well as a positive significant relationship between perceptions and satisfaction.
As the previous research, if existing goods or services please clients, they would continue to re-purchase or
support a service or preferred items in the future. However, the findings showed that “Satisfaction” had little
influence on the respondents' “Intention” to choose a bus. This result may imply that, in the context of HCMC,
just enhancing bus service and boosting customer happiness would not greatly affect citizens' decisions touse a bus. This may be explained by the fact that individuals in HCMC specifically and in Vietnam in general
have a strong habit of using personal vehicles and believe that owning a personal vehicle makes movingaround more convenient. Therefore, in addition to improving bus service and increasing passenger
satisfaction, the government needs to take simultaneous actions to change people's personal vehicle use habits.