Table 4: Significant variables and the possible reasons for the signs, single truck crashes, Wyoming Interstates.

Variable	Relationship	Possible Reason
Female truck driver	It increases the odds of injury/fatal single truck crashes.	Women are less able to sustain physical trauma.
Wet roadway surface condition	It decreases the odds of injury/fatal single truck crashes.	Drive more cautiously, with less speed, on not-dry-road conditions.
Increased posted speed limit	It increases the odds of injury/fatal single truck crashes.	Drive faster in higher posted speed limit locations.
Rollover/Jackknife	It increases the odds of injury/fatal single truck crashes.	Increased the contact of driver with road and vehicle.
Driver distraction	It increases the odds of injury/fatal single truck crashes.	Drivers are less cautious about the hazard associated with Wyoming mountainous area.