Practical Minimum Sample Size for Road Crash Time-Series Prediction Models

Table 4

The selected best-fit models for each sample size of all subject countries.

Country	Sample size	Best-fit ARIMA model	Model fit statistics
			Stationary R-squared	R-squared	MAE
Denmark	45	(2, 2, 2)	0.361	0.966	523.517
	35	(1, 2, 3)	0.411	0.979	292.596
	25	(1, 2, 3)	0.545	0.975	271.426
	15	(2, 2, 3)	0.488	0.947	276.796
Turkey	45	(2, 2, 3)	0.389	0.984	3851.541
	35	(2, 2, 3)	0.393	0.977	4515.151
	25	(2, 2, 3)	0.505	0.981	4189.615
	15	(1, 2, 2)	0.193	0.966	5514.014
Germany	45	(2, 2, 3)	0.519	0.742	12101.438
	35	(2, 2, 3)	0.538	0.780	12001.359
	25	(3, 2, 1)	0.308	0.821	11446.555
	15	(3, 2, 2)	0.712	0.834	6934.599
Israel	45	(0, 2, 1)	0.246	0.863	1095.791
	35	(0, 2, 1)	0.255	0.874	1132.513
	25	(2, 2, 3)	0.347	0.881	1181.735
	15	(2, 2, 3)	0.662	0.813	665.480