The overall accident rate of the highway will be the sum of the four submodels. Phase 3 Phase three is a long-term goal. To improve our ability to predict accidents, new techniques need to be developed. For example, future accident prediction modules could be based on simulations involving the geometric design elements that are stored in the CAD package, the traffic module, and the driver module. This appears to be the only way to deal with the third issue discussed earlier - low R 2 values.
Accidents are relatively rare events in terms of the number of vehicles and drivers on the road.
The interactions that can occur from an accident are very complicated. This interaction complicates the task of sorting out the safety effect attributable to a specific geometric feature. However, there may be an explanation for the low R 2 values. Figure 3 presents some findings from a study that compares causes of accidents in the United States and Great Britain. Taken at face value, this suggest that road-related elements are associated with 34 percent of crash causation.