Table 2.

Variable name and attribute.

Variable properties	Variable name	Satisfaction (0–5)	Flight operation quality	Departure arrival time convenient
Numerical type	Age		Ticketing service	Ease of online booking
	Flight distance			online boarding
			Ground service	Gate location
	Departure delay in minutes			Baggage handling
				Checking service
	Arrival delay in minutes		Air service	Inflight Wi-Fi service
				Food and drink
Category type	Gender			Seat comfort
	Type of travel			Inflight entertainment
	Customer type			Onboard service
				Leg room service
	Customer class			Inflight service
				Cleanliness