TABLE 1.

Hypothesis of latent variables.

Latent variables		Observed variables
Road characteristics		Traffic volume (R1), traffic complexity (R2), road complexity (R3)
Driver characteristics		Gender, age, driving experience
Driver states		Emotional state (S1), state of fatigue (S2)
Distracting elements		Mobile phone use (D1), conversation (D2), eating (D3), in-vehicle devices (D4), absent-mindedness (D5), conditions outside the vehicle (D6)
Driver cognitive abilities		Visual processing skills (C1), working memory capacity (C2), spatial perceptual ability (C3), time-sharing ability (C4)
SA	Perception	Vehicles or pedestrians (SA11), traffic signs (SA12), speeds (SA13), perceived hazards (SA14)
	Understanding	Location/speed of vehicles around (SA21), sign content (SA22), sign line meaning (SA23), driving time (SA24), speed limit value (SA25), road name (SA26)
	Prediction	Safe overtaking/lane change/acceleration (SA31), driving behavior of surrounding vehicles/pedestrians at the next moment (SA32), predicting driving time (SA33)