This study examines traffic behavior in the vicinity of a freeway bottleneck, revisiting commonly held assumptions and uncovering systematic biases that likely have distorted empirical studies of bottleneck formation, capacity drop, and the fundamental relationship (FR). This simulation-based study examines an on-ramp bottleneck using Newell's lower order car following model with a driver relaxation factor added for the vehicles that enter or are immediately behind an entering vehicle (termed "affected vehicles"). The affected vehicles will tolerate a truncated headway for a little while after an entrance but slowly relax back to their preferred speed-spacing relationship. All other vehicles remain on their preferred speed-spacing relationship throughout.
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