## 3 Methods
### Data  
This research utilized snowball sampling, a technique in which participants initially selected are asked to refer other potential participants from their network for inclusion in the study. The questionnaire was distributed to commuters who used BMTA's bus service in Bangkok via an online questionnaire. This questionnaire was distributed by researchers to their friends and relatives residing in Bangkok with a request for them to share it with acquaintances. Moreover, the survey was distributed through social media platforms such as Facebook and Instagram to encourage Bangkok residents to participate and complete the online questionnaire. To ensure the randomness and representativeness of the sampling process, at the very beginning, respondents were asked if they had ever taken a bus in Bangkok. If they had not, they were asked to discontinue the survey. Furthermore, the questionnaire also inquired about the frequency of the respondents' bus usage in order to ensure their suitability as survey participants for this study. Since the population size was 438,414 according to the BMTA in 2019, the sample size was calculated to be 399.635381 based on the formula of Yamane [66] with a 95% confidence level.  
A total of 429 commuters participated in this study, and all of the questionnaires were completed and usable. A total of 61.5% were female; most were 26-35 years old (42.2%), and some were 36-45 years old (34.7%); 23.3% were office workers in private enterprises, and 19.6% were office workers in state-owned enterprises; 41.3% were taking a bus with the purpose of going to work, and 15.9% were sending children to school; 54.5% were taking a bus 4-6 days per week, and 28.2% were taking one 2-3 days per week. The sample structure of this study was similar to that of previous studies on Bangkok buses (e.g., Wethyavivorn and Sukwattanakorn [10] and Ueasangkomsate [11]), which demonstrated that the sample of this study had a certain level of representativeness.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Dimensions** & & **Attributes** \\ \hline \multirow{3}{*}{Convenience of service} & 8. & Provided with schedule and route information on the bus and at the bus stop. \\ \cline{2-3}  & 9. & Availability of online bus schedules on the internet or a mobile application. \\ \cline{2-3}  & 10. & Convenience of a fare payment system. \\ \hline \multirow{3}{*}{Operating management support} & 11. & Buses operated punctually according to the schedule. \\ \cline{2-3}  & 12. & The bus company informs customers of changes in the timetable and prices in advance. \\ \hline \hline \end{tabular} Source: this study.  
\end{table}
Table 2: Cont.  
[PERSON]'s \(\alpha\) was employed to assess the reliability of satisfaction in this study. The [PERSON]'s \(\alpha\) of \"interaction with passenger\" (with 4 items) was 0.94, \"tangible service equipment\" was 0.89 (with 3 items), \"convergence of service\" (with 3 items) was 0.88, and \"operating management support\" (with 2 items) was 0.86. The results showed that the data in this research had a high level of reliability because the \(\alpha\) of satisfaction was greater than 0.7 in the above four dimensions of service quality.