CMF / CRF Details
CMF ID: 9770
Install adaptive traffic signal control
Description: ATSC is a traffic management strategy in which traffic signal timings change, or adapt, based on observed traffic demand. These systems utilize increased detection to continually collect data on observed demand, and signal timings are then re-optimized based on current data.
Prior Condition: Traditional traffic signal
Category: Intersection traffic control
Study: Estimating Safety Effects of Adaptive Signal Control Technology using the Empirical Bayes Method, Khattak et al., 2018
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 95 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 0.77 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.057 |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | 23 (This value indicates a decrease in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 5.7 |
| Applicability | |
|---|---|
| Crash Type: | Multiple vehicle |
| Crash Severity: | All |
| Roadway Types: | Not specified |
| Street Type: | |
| Minimum Number of Lanes: | |
| Maximum Number of Lanes: | |
| Number of Lanes Direction: | |
| Number of Lanes Comment: | |
| Crash Weather: | Not specified |
| Road Division Type: | |
| Minimum Speed Limit: | |
| Maximum Speed Limit: | |
| Speed Unit: | |
| Speed Limit Comment: | |
| Area Type: | Urban and suburban |
| Traffic Volume: | |
| Average Traffic Volume: | |
| Time of Day: | All |
| If countermeasure is intersection-based | |
| Intersection Type: | Roadway/roadway (not interchange related) |
| Intersection Geometry: | 4-leg |
| Traffic Control: | Signalized |
| Major Road Traffic Volume: | |
| Minor Road Traffic Volume: | |
| Average Major Road Volume : | |
| Average Minor Road Volume : | |
| Development Details | |
|---|---|
| Date Range of Data Used: | |
| Municipality: | Pittsburgh |
| State: | PA |
| Country: | United States |
| Type of Methodology Used: | Before/after using empirical Bayes or full Bayes |
| Sample Size (sites): | 29 sites before, 29 sites after |
| Sample Size (site-years): | 104 site-years before, 99 site-years after |
