Research Instruments/QuestionnaireT

Research Instruments/Questionnaire
The research questionnaire, consisting of sixty-one questions, was divided into six
parts and was prepared in the Thai language, which was most suitable for the
understanding of respondents. The first part contained screening questions which
confirmed that the right target population was chosen.
In the second part, respondents were asked their demographic profiles. The third
part, respondents were asked their own vehicle characteristics and fuel consumption by
using closed-ended question as adapted from Isarasaena-Na-Ayutthaya,
Rongviriyapanith, Vichearnsan, and Sanyaluklurchai (2006).
In the fourth part, the social influence attitude used 13 questions based on a five
point Likert scale, ranging from strongly disagree (1) to strongly agree (5). In the fifth
part, NGV attributes consisted of 32 questions which are also based on Likert five point
scales method asking degree of agreement.