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Need a PhD Topic? How about cops in traffic

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Re: Need a PhD Topic? How about cops in traffic

#31

Post by IanDrake »

gwern wrote: post #27
IanDrake wrote: post #23

>a police car introduces certain mental restrictions which prevent people from behaving how they naturally would. Just FYI, there's a reason for the mental restriction. If you pass a cop and you're in his jurisdiction and you're going faster than the speed limit you have about a 80% chance of getting a speeding ticket. 80% is the shaky number I came up with based on witnessing 5 occurrences. I was a one driver that g…

So actually your number, by Laplace's law of succession ( http://en.wikipedia.org/wiki/Rule_of_succession ), would be 71%: you saw 4 other instances and you were another instance, so that's 5 instances, and you say you and 3 others were pulled over for 4 pull overs, so in the formula 's +1 / n + 2' we get ' 4+1 / 5+2' or 0.71 or 71%.

Interesting. I'm a simpleton when it comes to this stuff.

Re: Need a PhD Topic? How about cops in traffic

#32

Post by ojbyrne »

My personal pet peeve is the number of times I've seen police officers breaking traffic regulations. I was hoping someone would study that (and actually make them stop). Speeding, tailgating, illegal lane changes, etc. etc. They're not supposed to do any of that without a siren.

Re: Need a PhD Topic? How about cops in traffic

#33

Post by IanDrake »

grecy wrote: post #25
IanDrake wrote: post #23

>a police car introduces certain mental restrictions which prevent people from behaving how they naturally would. Just FYI, there's a reason for the mental restriction. If you pass a cop and you're in his jurisdiction and you're going faster than the speed limit you have about a 80% chance of getting a speeding ticket. 80% is the shaky number I came up with based on witnessing 5 occurrences. I was a one driver that g…

I've often tested the theory myself, without breaking the speed limit. If the cop is driving just under the limit, I set my speed exactly on the limit, and overtake if I need to. Of the ~10 times I've done this, I once got pulled over and abused by the cop for being a "freaking idiot". No ticket.

>without breaking the speed limit

Yeah, I pass cops all the time without breaking the limit and have yet to get pulled over.

Though, I did get the "freaking idiot" riot act the time I got pulled over for passing above the limit.

Re: Need a PhD Topic? How about cops in traffic

#34

Post by mindslight »

IanDrake wrote: post #23

>a police car introduces certain mental restrictions which prevent people from behaving how they naturally would. Just FYI, there's a reason for the mental restriction. If you pass a cop and you're in his jurisdiction and you're going faster than the speed limit you have about a 80% chance of getting a speeding ticket. 80% is the shaky number I came up with based on witnessing 5 occurrences. I was a one driver that g…

Here in Massachusetts, the staties blow by you at 100MPH (and when people don't move over, sit on their tail and probably give them a good scare when they finally realize what's behind them). I generally see them coming from pretty far back (a car closing at ~25mph is pretty noticeable), move over, let them pass, then see how long I can follow. I figure that the cop must be following the law and going a safe speed for the conditions of the road, so I can use them as a benchmark for what is considered acceptable instead of having to rely on the purely advisory signs.

Funnily enough, the slow cops and coplike vehicles that bunch up traffic are usually the ones with the least jurisdiction and least likely to give out tickets. Town cops going one exit on a state road, inmate transfer, game wardens, etc. This could of course all be fixed by having speed limits that reflected society, and GPS tracking of cops to make sure they're not immune from the law. But more likely self driving cars will make the whole situation moot - I'd gladly save fuel and make a 2hr trip in 3hrs if I didn't have to waste my attention on the vehicle.

Re: Need a PhD Topic? How about cops in traffic

#35

Post by larrydag »

politician wrote: post #21
larrydag wrote: post #4

Earlier quoted context omitted.

I could see this being possibly useful in traffic "wave" disruption. I've read on the traffic wave theory before and there has been some ideas that if the wave could be disrupted long enough to clear out that it would dissolve and traffic would start to flow again at its normal pace. I suppose that disruption could be done by police cars allowing buffers to build thus disrupting the wave. Can you tell I find this fie…

One of those papers mentioned in the article described "negative traffic" as the gaps in an otherwise saturated segment of road. Vehicles travelling behind the gap tended to have smoother acceleration curves. I've used this idea to great effect when stuck in traffic by moving into the far left lane, building up a nice gap in front of me, and then cruising at a steady 2-3mph instead of stop-and-go. I've noticed that p…

Here is a DIY traffic wave experiement I read on this topic. http://www.eskimo.com/~billb/amateur/traffic/traffic1.html. Pretty interesting results.

bump: sorry. the remaining links look broken

Re: Need a PhD Topic? How about cops in traffic

#36

Post by slysf »

mindslight wrote: post #34
IanDrake wrote: post #23

>a police car introduces certain mental restrictions which prevent people from behaving how they naturally would. Just FYI, there's a reason for the mental restriction. If you pass a cop and you're in his jurisdiction and you're going faster than the speed limit you have about a 80% chance of getting a speeding ticket. 80% is the shaky number I came up with based on witnessing 5 occurrences. I was a one driver that g…

Here in Massachusetts, the staties blow by you at 100MPH (and when people don't move over, sit on their tail and probably give them a good scare when they finally realize what's behind them). I generally see them coming from pretty far back (a car closing at ~25mph is pretty noticeable), move over, let them pass, then see how long I can follow. I figure that the cop must be following the law and going a safe speed fo…

"I'd gladly save fuel and make a 2hr trip in 3hrs if I didn't have to waste my attention on the vehicle."

Isn't that the bus/train?

Re: Need a PhD Topic? How about cops in traffic

#37

Post by mindslight »

slysf wrote: post #36
mindslight wrote: post #34

Earlier quoted context omitted.

Here in Massachusetts, the staties blow by you at 100MPH (and when people don't move over, sit on their tail and probably give them a good scare when they finally realize what's behind them). I generally see them coming from pretty far back (a car closing at ~25mph is pretty noticeable), move over, let them pass, then see how long I can follow. I figure that the cop must be following the law and going a safe speed fo…

"I'd gladly save fuel and make a 2hr trip in 3hrs if I didn't have to waste my attention on the vehicle." Isn't that the bus/train?

bus/train won't get you door to door, so you get further expense (monetary or social) at both ends (coupled with more pay-attention time). plus the added coordination time due to not wanting to miss your departure. i've done the bus, and i'd estimate it's more like adding 2hr of non-attention to the existing 2hr of pay-attention.

bus/train also requires packing/bundling and simultaneous handling of cargo, where with a car, you can just throw everything in the trunk/back seat at your leisure.

Re: Need a PhD Topic? How about cops in traffic

#38

Post by lesterbuck »

larrydag wrote: post #35
politician wrote: post #21

Earlier quoted context omitted.

One of those papers mentioned in the article described "negative traffic" as the gaps in an otherwise saturated segment of road. Vehicles travelling behind the gap tended to have smoother acceleration curves. I've used this idea to great effect when stuck in traffic by moving into the far left lane, building up a nice gap in front of me, and then cruising at a steady 2-3mph instead of stop-and-go. I've noticed that p…

Here is a DIY traffic wave experiement I read on this topic. http://www.eskimo.com/~billb/amateur/traffic/traffic1.html . Pretty interesting results. bump: sorry. the remaining links look broken

I read the same article a while ago and added it to my (long) list of business proto-ideas. Here are the notes I scribbled a few years ago:

"Build a web app/site that allows people to practice smoothing out waves, speed up time to see effects easily, animate the process for visual understanding, etc., etc. Maybe even issue stickers so one can identify people who are smoothers rather than just people cutting in line."

Lately, a mobile app or an app built into the car's computer system could coordinate smoothing actions with other cars, and give some feedback on real time smoothing.

Re: Need a PhD Topic? How about cops in traffic

#39

Post by IanDrake »

mindslight wrote: post #34
IanDrake wrote: post #23

>a police car introduces certain mental restrictions which prevent people from behaving how they naturally would. Just FYI, there's a reason for the mental restriction. If you pass a cop and you're in his jurisdiction and you're going faster than the speed limit you have about a 80% chance of getting a speeding ticket. 80% is the shaky number I came up with based on witnessing 5 occurrences. I was a one driver that g…

Here in Massachusetts, the staties blow by you at 100MPH (and when people don't move over, sit on their tail and probably give them a good scare when they finally realize what's behind them). I generally see them coming from pretty far back (a car closing at ~25mph is pretty noticeable), move over, let them pass, then see how long I can follow. I figure that the cop must be following the law and going a safe speed fo…

Yeah, I'm from the Cape. Never had to pass a state cruiser. I dive a lot in CT though and their staties never drive fast without their lights going.

One time I had to call 911 for a drunk driver and the dispatcher asked me to follow the guy saying I could drive as fast as I felt safe. I was about 1/2 mile behind the guy going 95 mph when the cruiser passed me like I was standing still (with no siren or lights). I'd swear he was going 140.

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