The detailed procedure of the experiments are shown as below.
1) Before the test, we inform the participants the following items.
- The goal of the experiment is to distinguish (Driver B: V2) whether the opponent driver (Driver A: V1) is a human or an algorithm based on the interaction.
- The task of the scene as is depicted in Note S1, Supporting Information.
- The driver should follow the traffic rules.
- Their primary task should be the task of the scene: they should drive normally; the secondary task is the goal of the experiment: they can try to test vehicle 1. This is important because we think the driver should behave reasonably, but at the same time, it is necessary to give pressure to vehicle 1. When driving too cautious, without any conflict of interest, it is hard to evaluate the performance of vehicle 1. Also, the proposed algorithm is for scene generation. A human-like way to trigger an accident is sometimes needed.
- The driving style of the algorithm is randomly generated before each test.
- One single test takes 20 seconds and there will be a total of 10 tests for each participant
2) Two participants have few test rounds till they are familiar with the simulator and the dynamic performance of the vehicles. 3) After enough practice, driver B chooses to drive in autonomous mode or fully manual mode. If Driver B chooses autonomous mode. She or he also generates random driving style parameter (\(\alpha_{th}\)). Driver A cannot see this process. 4) Driver B initiates one test and before the start of the test, Driver B informs Driver A so that Driver A can be well prepared for the experiment. 5) Complete one test. 6) Fill in a questionnaire. 7) Repeat step 3) to 6) nine more times. 8) score the entire experiment using Table in Note S7, Supporting Information. 9) After one set of tests, Driver B will be asked what is the criteria for their judgments.