Table 1.

Descriptive statistics of variables.

Variables	Definitions	Units	Min.	Max.	Mean	Std.dev
population density	The ratio of the resident population to land area	person/km2	4.10	56.79	28.13	14.57
aged people density	The ratio of the aged people population to land area	person/km2	0.15	3.05	1.42	0.79
built-up density	The ratio of total built-up area to the land area	%	39	100	66	16
Road density	The ratio of total roads area to the land area	%	0.003	0.73	0.21	0.21
Trip generation rate	the number of trips that are generated by the residents of districts	Trip/person	0.68	1.81	1.08	0.28
Car ownership	The number of cars per 1000 inhabitants	Cars/1000 people	37.54	75.79	55.15	13.09
Distance to metro station	The average distance of neighborhoods to metro station	m2	243/16	2665/94	999/17	680/06
Distance to bus station	The average distance of neighborhoods to metro station	m2	243/16	542/16	254/42	89/58
Literacy rate	The ratio of literate persons to total population	%	90.00	98.00	94.45	2.91
Percentage of college-educated	The ratio of college-educated persons to total population	%	7.9	45.19	21.7	11.5
employment rate	The ratio of the number of employed persons to the active persons	%	86.00	92.00	88.55	1.68
Sex ratio	The ratio of males to females in the population of a district	Males/100 females	91.91	103.88	99.38	3.39
Average income	The average income earned per person in a given district	Tomana/person	1.6	2.2	1.9	0.17

^aToman is the official currency of Iran.