Analyzing Household Vehicle Ownership in the Japanese Local City: Case Study in Toyota City

Table 2

Estimation model for complementing annual income.

Explanatory variable	Parameter	Standard deviation	T-statistic
Householder: female (dummy)	−0.241	0.026	−9.43
Number of members in one household	0.022	0.007	3.25
Householder: ≥25 & ≤34 years old (dummy)	0.131	0.083	1.59
Householder: ≥35 & ≤44 years old (dummy)	0.273	0.082	3.34
Householder: ≥45 & ≤54 years old (dummy)	0.398	0.082	4.87
Householder: ≥55 & ≤64 years old (dummy)	0.299	0.084	3.57
Householder: ≥65 years old (dummy)	0.489	0.089	5.47
District: Mie prefecture (dummy)	0.014	0.021	0.65
District: Aichi prefecture [excluding Nagoya] (dummy)	0.026	0.018	1.45
District: Nagoya (dummy)	0.096	0.019	5.21
Householder: government employee (dummy)	0.637	0.028	22.60
Householder: company employee (dummy)	0.457	0.023	19.86
Householder: self-employed business (dummy)	0.190	0.028	6.68
Household: stand-alone building (dummy)	0.025	0.015	1.75
Number of family members [≥25 years old]	0.086	0.013	6.83
Number of workers in the household	0.088	0.009	9.45
Constant	5.189	0.085	61.34
Standard deviation of the error item	0.454	0.005	98.01
Threshold value 1	Log (200)
Threshold value 2	Log (300)
Threshold value 3	Log (400)
Threshold value 4	Log (500)
Threshold value 5	Log (600)
Threshold value 6	Log (700)
Threshold value 7	Log (800)
Threshold value 8	Log (1000)
Threshold value 9	Log (1500)
Log-likelihood at zero	−13276.706
Log-likelihood at convergence	−11883.870
McFadden’s rho-squared	0.105
Adjusted McFadden’s rho-squared	0.104

Threshold values indicate the maximum or minimum value of income categories. The threshold values log (200) and log (300) are used for the annual income category from 200 to 300 (unit: 10 thousand million JPY) [17].