We cannot apply a perception-response time (or use the chart above) until an object is easily identified as an immediate hazard (Conspicuous).
Objects: A "stimulus" or object as defined in this research is something the driver was responding to. Therefore, if there are 5 other cars, 2 birds, 4 pedestrians and one of them come into the driver's path, then that would be a response analysis for a response to one stimulus. A multiple stimulus event is if the driver was responding to one object and within 0.1 to 1.5 second later, he or she was expected to respond to a second object. The first object could be a car, dialing a cell phone, or anything else that required a response. If a driver is already engaged in one response, his or her response to a second object will be delayed by approximately 0.5 seconds when responding to a lead vehicle and approximately 0.7 seconds when responding to a path intrusion.
Straight versus Curve/Cue/Intersection: Straight means there were no significant changes in elevation in the immediate area. You could have a straight upward grade, flat grade or downward grade (less likely). Otherwise, select Curve/Cue/Intersection if responding (or expected to respond) after the knoll of a hill, entering or within a curve in the road or entering or within an intersection.
Day or Night: Select Day if before sunset, night if after sunset and if dusk, look at the range between column for "Day" and "Night".