n preparation for the sunsetting of Safety Analyst in July 2022, AASHTOWare Safety has recently completed a third-party validation of all AASHTOWare Safety Network Screening calculations and methodologies to ensure adherence to HSM recommendations and best practices.
The Texas A&M Transportation Institute (TTI) recently published its report, “Validation of the AASHTOWare Safety powered by Numetric Network Screening Calculations” which validates several key areas within AASHTOWare Safety, including:
- Performance Measures | During the validation process, the 12 Performance Measures available in AASHTOWare Safety were found to be in alignment with the calculations previously generated by Safety Analysis, and the Highway Safety Manual (HSM).
“Based on the validation test procedures, it was confirmed that the Beta version of the Numetric software used for this validation testing properly and accurately calculates network screening performance measures for rural two-lane, two-way roads in accordance with procedures described in the HSM.”
– TTI Validation Report
- Predictive and Expected Methods | The report also validates the ability to implement SPFs, and generate accurate Empirical Bayes expected performance measures, allowing for the use of Historical, Presided, and Expected Performance Measures throughout the AASTHOWare Safety platform.
“In particular, the Numetric software properly implements SPFs to accurately calculate predicted crash frequencies and rates and Empirical Bayes (EB) methods which combine observed and predicted crashes to accurately calculate expected crash frequencies and rates. Based on these foundational procedures, a range of performance measures based on predictive and EB methods are accurately calculated and available for network screening in the Numetric software for rural two-lane, two-way roads.”
– TTI Validation Report
