Table 1.

A list of studies on investigating the influence factors of road transport emissions.

Year	Studies	Country	Targets	Influence Factors
2005	[15]	UK	Passenger	Emission coefficient; Fuel structure; Fuel intensity; Occupancy rate; Distance per person; Population.
2007	[11]	Taiwan, Germany, Japan and South Korea	Road Transport	Emission factor; Population intensity; Vehicle ownership; Fuel intensity; Economic growth.
2009	[16]	Greece and Denmark	Passenger	Ownership effect; Distance; Fuel mix; Car capacity change; Car engine change; Population.
2012	[17]	China	Freight	Carbon intensity; Vehicle technology level; Vehicle load; Transport company size; Number of transport companies; Distance; Relations between freight transport and industrialisation; Level of industrialisation; Economic growth.
2013	[18]	China	Freight	Emission factor; Market concentration; Road freight market share; Industrialisation level; Fuel intensity; Economic growth.
2014	[19]	Tunisia	Freight	Emission intensity; Energy intensity; Transport intensity.
2015	[12]	China	Road Transport	Share of vehicle types; Energy intensity of vehicle types; Emission intensity of vehicle types.
2017	[20]	Tunisia	Road Transport	Energy intensity; Economic development level; Urbanisation; Motorisation, Energy consumption.