I'd like to see if its possible to provide a "simulation setting" setpoint for "optional advantage." Currently we have location-adjustable settings for lane changes (mandatory distance and positioning distance) but not for queue behavior at signals.

In a lot of rural settings, or less developed urban settings, a traffic signal will have a "lane add" upstream followed by a "lane drop" some distance downstream of the signal. Typically this is intended to increase capacity of the signal in an inexpensive manner, by minimizing pavement costs. However, lane utilization at these can vary to an extreme depending on based on downstream length and driver familarity. Vehicles may tend to queue up to a greater degree in some circumstances than in others. Adjusting "positioning distance" and "mandatory distance" may enable the user to mimic the Lane utilization in the field, but often not the behavior. What I typically see in SimTraffic is that a higher positioning distance tends to prevent most drivers from getting in the lane, but sometimes those that do will get in the second lane (in order to "jump the queue"), but stop before the stop bar to attempt to get back in the queue line, sometimes leaving a lot of space in front of the car. If we had a location specific adjustment for optional advantage in the "simulation settings" it might be possible to reduce or correct this behavior.

Eric Royer
Caltrans

Hi Eric,

Thanks for the comments on the setting. I do understand what you are saying and we will look into this. You might also try adjusting the Options>Driver-Paramter settings for Positioning Advantage and Optional Advantage. Smaller values would tend to make vehicles proceed further down.

Thanks for the suggestion,

John

Thanks john, that's what I have been forced to do pretty much. field data collected shows a lane utilization of about .55-.56 at the location in question. I didn't want to have to change a global paramater though, since now 3 other intersections are impacted by this change in driver behavior. Which, is why I was hoping that in the future it would be possible to adjust this from a default setting on a location specific basis if need be.

Eric