Table 2 Descriptive statistics of key variables in the models.

Temporal characteristics

Time between 12 AM to 5:59 AM indicator (1 if crashes occurred between 12 AM to 5:59 AM, 0 otherwise)

Time between 10 AM to 3:59 PM indicator (1 if crashes occurred between 10 AM to 3:59 PM, 0 otherwise)

4th quarter indicator (1 if crashes occurred between October to December, 0 otherwise)

Analysis period 2018 indicator (1 if crashes occurred in 2018, 0 otherwise)

Analysis period 2017 indicator (1 if crashes occurred in 2017, 0 otherwise)

Ambient weather characteristics

Clear weather indicator (1 if crashes occurred in the clear weather, 0 otherwise)

Crash characteristics

Rollover indicator (1 if crashes were rollover, 0 otherwise)

Unknown type rollover (1 if crashes were rollover with unknown type, otherwise 0)

No Rollover indicator (1 if crashes were not rollover, 0 otherwise)

Vehicle running off from the left of the roadway indicator (1 if a vehicle ran off the roadway from the left side of the roadway, 0 otherwise)

Vehicle running off the roadway indicator (1 if a vehicle ran off the roadway, 0 otherwise)

Right or left roadside departure (1 if a vehicle ran off right or left roadside departure, 0 otherwise)

Live animal indicator (1 if crashes involving live animals, 0 otherwise)

Tree indicator (1 if crashes involving with trees, 0 otherwise)

Number of occupants indicator (1 if crashes involving 1 occupant, 0 otherwise)

South indicator (1 if crashes occurred in the south region of the country, 0 otherwise)

On roadway (1 if crashes occurred on roadway, otherwise 0)

Vehicle characteristics

Motorcycle involvement indicator (1 if crashes involving motorcycle, 0 otherwise)

Displacement up to 2500 cc indicator (1 if crashes involved with the vehicles for displacement up to 2500 cc, otherwise)

Displacement ranging from 5000 to 10,000 cc indicator (1 if crashes involved with the vehicles for displacement from 5000 to 10001 cc, otherwise)

Newer vehicle indicator (1 if crash involved with vehicles that were manufactured within 5 years from the year of crash, 0 otherwise)

Vehicles manufactured by Chevy and Ford indicator (1 if crashes involved with vehicles manufactured by Chevrolet and Ford, 0 otherwise)

Body type other indictor (1 if crashes involve buses, motor home, snowmobiles, farm vehicles, etc., 0 otherwise)

Roadway characteristics

Non-interstate indicator (1 if crashes occurred on non-interstate, 0 otherwise)

Two-way with positive median barrier indicator (1 if the crashes occurred on two-way roadway with positive median barrier, 0 otherwise)

Two-way undivided roadway indicator (1 if the crashes occurred in two-way undivided roadway, 0 otherwise)

Curved roadway indicator (1 if crashes occurred on curved roadways, 0 otherwise)

Straight roadway indicator (1 if crashes occurred on straight roadways, 0 otherwise)

Dry surface indicator (1 if crashes occurred on dry surface, 0 otherwise)

Wet surface indicator (1 if crashes occurred on wet surface, 0 otherwise)

Driver characteristics

Male driver indicator (1 if male driver involved in crash, 0 otherwise)

Female driver indicator (1 if female driver involved in crash, 0 otherwise)

Drives age below 26 years (1 if drivers involved in crashes were below 26 years old, 0 otherwise)

Drives age from 35 to 45 years (1 if drivers involved in crashes were between 35 to 45 years old, 0 otherwise)

Reckless driving indicator (1 if crashes occurred due to reckless driving, 0 otherwise)

Driving under the influence (1 if crashes occurred due to driving under the influence, 0 otherwise)

Drinking indicator (1 if drivers involved in crashes were drinking, 0 otherwise)

No drinking indicator (1 if drivers involved in crashes were not drinking, 0 otherwise)

Non-restraint usage indicator (1 if no restraint was used, otherwise)

Restraint usage indicator (1 if restraint used, otherwise)