A Roadway Safety Sustainable Approach: Modeling for Real-Time Traffic Crash with Limited Data and Its Reliability Verification

Table 3

Significant variables in small sample data sets.

Data sets	Risk factors
5% small sample	up_s
10% small sample	up_s, down_v, abs_dif_s, and up_dif_v
20% small sample	up_s, down_s, up_o, and down_v
30% small sample	up_s and down_dif_v
50% small sample	up_s, down_dif_v, up_dif_s, and abs_dif_o

At the level of significance of 0.05.