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Federal and state transportation agencies set goals related to surface transportation system performance. The variability in factors influencing design criteria (e.g., driver performance, road conditions, and vehicle performance) is often large and is addressed implicitly by using "conservative" values....

This study evaluated the approach-level safety performance of left-turn phases at signalized intersections, including permissive, protected-permissive (PPLT), protected indications, and flashing yellow arrow (FYA). Data collection included exact dates of traffic signal changes, high-resolution datasets...