# Buy and/or Pay Disparity: Evidence from Fully Autonomous Vehicles
## 3 Methodology
### Data
We used a payment card method to measure PV, and we provided detailed ranges of PVs in Table 1. However, given that FAVs are a newly introduced technology, people may not have a specific price range of PV if we choose to leave PV as an open question. In that sense, leaving PV as an open question may increase the variances of responses for two reasons. First, because evaluating PV is not a typical daily decision-making behavior, it may result in many nonresponses, and respondents would feel that it is difficult to answer with a concrete number without providing any examples. Second, following the first reason, the number of outliers may increase, and the outliers may distort the representative values by abnormally large or small amounts. Third, the answers tend to be concentrated on round numbers (Ministry of Land, Transport, and Infrastructure--We refer to [[https://www.mlit.go.jp/kowan/beneki/images/kaigan_hiyoubeneki_06.pdf](https://www.mlit.go.jp/kowan/beneki/images/kaigan_hiyoubeneki_06.pdf)]([https://www.mlit.go.jp/kowan/beneki/images/kaigan_hiyoubeneki_06.pdf](https://www.mlit.go.jp/kowan/beneki/images/kaigan_hiyoubeneki_06.pdf)), accessed on 26 October 2023). Thus, we chose to use categorical but detailed PV questions. We have respondents who chose a PV of 0, indicating that they would choose to add it if it is free, and such an answer does not indicate that the respondents are not willing to purchase AVs. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & \multicolumn{3}{c}{**Please Write Down Your Willingness-to-Pay for Adding**} \\  & **Fully Automated Option to Your Newly Purchased Vehicle.** & \\ \hline
**Group** & **Range (10,000 JPY)** & **Frequency** & **Proportion (\%)** \\ \hline
1 & 0 & 40,093 & 22.18 \\ \hline
2 & 1–5 & 34,666 & 19.18 \\ \hline
3 & 6–10 & 27,456 & 15.19 \\ \hline
4 & 11–15 & 11,331 & 6.27 \\ \hline
5 & 16–20 & 14,987 & 8.29 \\ \hline
6 & 21–25 & 4067 & 2.25 \\ \hline
7 & 26–30 & 18,511 & 10.24 \\ \hline
8 & 31–35 & 2346 & 1.30 \\ \hline
9 & 36–40 & 1179 & 0.65 \\ \hline
10 & 41–45 & 569 & 0.31 \\ \hline
11 & 46–50 & 9524 & 5.27 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The range, frequency and respondents’ proportion of the willingness-to-pay (PV) in our survey. We also included the respondents' car ownership and car types in our model for two reasons. First, we would like to increase the survey's internal validity; therefore, we would like to control for individuals who do not know the price and maintenance costs for cars. Thus, we included the 'car ownership' variable to control for those who do not own a car and are less likely to be aware of car prices. Second, along with car ownership, we also include car types (gasoline, diesel, hybrid, plug-in-hybrids (PHEV), fuel-cell vehicle (FCV), and electric vehicles (EV)), as car prices differ according to the car types. Then, we asked about concern for the environment in the form of 'importance as a policy' on a 5-point Likert scale, including zero (no awareness). Based on previous studies, we classified the topics for environmental policy into eight factors referring to the House of Councilors, The National Diet of Japan, (2015) [57]; We have 13 questions in total, and the topics are about the renewable energies, air pollution, environmental conservation, water pollution, endangered species conservation (biodiversity), reuse and recycling, waste disposal, and CO2 emissions with questions such as, \"How important is the policy to you?\" The scale of responses is as follows: (0) for no awareness/interest at all-therefore, the difference between those who answer (0) and others would be whether that person at least has an interest in a certain policy/issue, (1) for very insignificant; (2) for insignificant; (3) for neither important nor insignificant; (4) for important; (5) for very important. Next, we surveyed the technological merits and concerns regarding FAVs. Respondents were asked to check multiple options among 17 options for merit and 12 options for concerns.