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Going Postal In The Security Line

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I've been reading a book called Traffic, by Tom Vanderbilt, which is well researched and fascinating essay on how people behave in traffic--cars, motorcycles, bicycles and pedestrians. He opens the book with a question: When faced with a sign announcing a lane drop ahead, is it better to merge early or merge late? I'll get back that in a minute.

Meanwhile, what I've learned in this book I have been able to apply directly to airport security lines, which I have been negotiating frequently due to a heavy travel schedule. There are three observations I'd make about how people work against their own interests and, because of cluelessness and lack of knowledge and courtesy, make it worse for the rest of us.

The Fat Captain--This happened to me when leaving Oklahoma City at Oh-Dark-Thirty last week. Only one security line was open and a flight crew, of course, butted to the front of the line. No complaint from me. They should be given this courtesy, but they should return it to their customers by being as minimally disruptive as possible.

So this overweight four striper is too fat to duck under the ribbon barrier so one of the TSA workers has to interrupt her scanning and unhitch the ribbon for him. But rather than merging into the line at the point where the plastic bins were, he waddled right up the baggage scanner conveyor, so the passengers had to pass four bins to him. He fumbled for his laptop and got that in the bin. Off to the body scanner. Forgot to remove his cellphone. Back to the belt to get another bin, jamming up two or three passengers. On his second run, he forgot to remove his shoes. Back to the conveyor, jamming up two more people.

Now I'm not saying this removal of the shoes and scanning is a good thing, but fer Chrisakes, we all know how it works by now. Next time, Skipper, how about having a cup of Joe before show time?

Overhead Hog-- Here's something I didn't know. The rule about putting one bag in the overhead and another under the seat isn't a rule at all. It's a policy and it isn't enforced, according to a flight attendant I asked. I asked because the jerk in the seat next to me felt it was his privilege to put both his bags in the overhead, denying me space for my one, which wound up 12 rows ahead of me. I only learned about this when he deplaned, dragging all of his crap out of my space.

This is a classic trashing of the freedom of the commons, which works splendidly for everyone when people take what they need and leave the rest, but doesn't work at all when they don't. It's called personal agency and responsibility and it grows ever rarer, even though its application benefits everyone.

Aisle Idiots--I boarded a flight in Newark and settled into the very last row. Standing next to me was a flight attendant on the PA trying to get people to step out of the aisle and into their seat rows so people could get past. We had a rapidly approaching departure slot and they were trying to get the thing pushed back. (Really, they just wanna get the doors closed and move the airplane so the two airplanes waiting for the gate can move in.)

She laughed when I asked if she would mind if I brought a bullhorn aboard next time and shouted from the back, "What the #$@% part of step out of the aisle didn't you understand?"

"We say it over and over again," she told me, "but people just ignore it." This is, of course, working counter interest, because ultimately, the pushback took forever and we got into a long conga line.

And last, the merge thing. You serve the freedom of the commons more efficiently by merging as late as possible, because even though you whiz by the early mergers, you're using all the available pavement for longer, so everyone moves faster.

Too bad security lines don't work like that.

Comments (68)

"merging as late as possible, because even though you whiz by the early mergers, youíre using all the available pavement for longer, so everyone moves faster..."

...well, yeah, until the bubble of empty pavement is filled up - at that point the flow rate goes right back to the flow rate determined by the constriction/single lane.

(I must really have nothing to do today if I am writing in about this)

Posted by: Anthony Nasr | February 9, 2010 12:31 PM    Report this comment

A captain that's an "overweight four-stripper?" Eeeww...

Posted by: Brad Koehn | February 9, 2010 12:58 PM    Report this comment

well, yeah, until the bubble of empty pavement is filled up - at that point the flow rate goes right back to the flow rate determined by the constriction/single lane.<<

Actually, no...but you gotta read the research report to understand why. People actually do study these things...

Posted by: Paul Bertorelli | February 9, 2010 2:25 PM    Report this comment

Ah, I plead spell checker insertion.

Posted by: Paul Bertorelli | February 9, 2010 2:28 PM    Report this comment

Are we loosing tolerance or are the times more testing ? Or just maybe : did the AlQaeda/Bush-tandem win through indirect sabotage of our society ?

Posted by: Peter De Ceulaer | February 10, 2010 4:40 AM    Report this comment

replace Bush with TSA in the previous post; it's a stab across party lines, really.

Posted by: Peter De Ceulaer | February 10, 2010 4:49 AM    Report this comment

Merge at the last of the pavement when there is no space to merge and bring both lanes to a complete stop. Smart, really smart!

Posted by: Unknown | February 10, 2010 5:14 AM    Report this comment

It is the problem of the "ME ME ME" society, where individual selfishness is rewarded rather than repelled. I welcome the occasional trucker who blocks the left lane so that the traffic can get back to speed again.

Posted by: Michael Schupp | February 10, 2010 5:39 AM    Report this comment

I've always wondered why the airlines can't figure out how to board from back to front, or let the window seats on first. Seems like a problem a high-school kid could solve with a laptop! Though I suppose if they made it too easy and rational to fly commercial, we wouldn't appreciate GA as much.

Posted by: Mary Grady | February 10, 2010 6:49 AM    Report this comment

As I approach geriatracism (?)I wonder if my instincts are right. I'd remove the additional bag and place mine. Then I'd lie and say I was there first. If someone is brash enough to be that rude I'll repay the favor with relish. My wife hasn't nicknamed me Crankshaft in vain.

Posted by: Michael Mahoney | February 10, 2010 8:13 AM    Report this comment

Regarding where to merge: I've determined the 'where' isn't as important as the 'how.' For some reason people are loathe to let another car into the lane ahead of them -- even back among the early mergers.

By butting the front end of his car against the rear of the car in front, a driver actively interferes with the merging process. He does this despite the knowledge merging MUST occur for all to make it through the lane restriction.

This 'merge interference' is exacerbated by drivers who merge early and take particular exception to those who attempt to merge late. Some even go as far as blocking the adjacent lane -- 18-wheelers are notorious for this.

This is a case of confusion born of ignorance devolving into self-righteous anger and bad citizenship. It seems to me those bothered by people merging late ahead of them should simply merge late themselves. That way they won't feel so compelled to interfere with others attempting to merge. The less merge interference, the faster everyone moves. As the old adage goes: If you can't beat 'em, join 'em!

Perhaps we need a government-sponsored study to find a solution, followed by a government-sponsored public service announcement from a few celebrity talking heads. Or maybe a new law or two.

Yeah, that would fix it...

Posted by: Mark Sletten | February 10, 2010 9:52 AM    Report this comment

>>Perhaps we need a government-sponsored study to find a solution, followed by a government-sponsored public service announcement from a few celebrity talking heads. Or maybe a new law or two.<<

Already been done. Quoting from Traffic: "The most surprising thing about the Late Merge concept is that it showed a 15 percent improvement in traffic flow over the conventional merge. It turns out that the Live Free crowd was right. Merging late, that purported symbol of individual greed, actually makes things better for everyone."

Posted by: Paul Bertorelli | February 10, 2010 10:01 AM    Report this comment

And I should explain why this is so. The researchers who study this stuff have something we as individuals don't. A lot of data points that, when plotted, show a pattern that can be quite the opposite of what we as individuals assume based on our limited personal experience.

While you may laud the trucker for blocking the lane or curse the driver who won't let you in to merge, those are outlying responses. The vast majority of the merges are smooth and courteous, possibly because drivers make an assessment about interest vs. counter interest. Or for some other reason.

Obviously, this varies by venue. Probably works better in Indiana and Florida than on the approaches to the GW Bridge.

Posted by: Paul Bertorelli | February 10, 2010 10:09 AM    Report this comment

My "gov't-sponsored' comments were poor attempts at irony, but thanks for sharing the data. It appears the research backs up my gut feeling: We would all benefit if those bothered by late mergers simply merged late themselves rather than try to punish or prevent it.

Posted by: Mark Sletten | February 10, 2010 10:15 AM    Report this comment

>>We would all benefit if those bothered by late mergers simply merged late themselves rather than try to punish or prevent it.<<

'zactly. Interest v. counter interest.

Posted by: Paul Bertorelli | February 10, 2010 10:39 AM    Report this comment

I entirely agree with the "late merge" strategy and I think the maximization of pavement explanation is pretty good...but doesn't quite explain the key point, which is: for freeway entrance merges (as opposed to highway lane restrictions) you have to look BACKWARDS at the line to see the common good. By maximizing pavement up at the front of the line, more vehicles can get through the traffic signal, which means fewer vehicles are stuck trying to get onto a ramp. This also provides a first-come-first-served benefit for the common good.

Of course, here in Saudi Arabia all bets are off because vehicles merge from any lane at any time and it's not unusual to see a driver simply mosey up in front of 4 lanes of traffic waiting for a light to change and then nose in front in order to make a left turn. Imagine if an airliner did that to a conga line at Newark!

Posted by: Jim Veihdeffer | February 10, 2010 12:18 PM    Report this comment

A little forethought and practice surely makes the TSA experience faster. More than once I've removed my running shoes and replaced them with slip-ons prior to leaving the house for the airport. Same goes for a quick repositioning of pants-pocket contents into a bag-side-pocket and making sure my toiletry ziplock is near the zipper of the carryon for fast removal. Just a bit of pre-planning and you can zip through. Like you said - it wasn't that Cap's first rodeo and surely he's familiar with procedures.

Regarding carryons, overheads, and aisle-ways; here is my suggestion: position a flight attendant at the front and rear of the plane. Fill the plane from back to front with a boarding reminder from the gate and at the boarding door to not deposit your luggage until at your seat (to prevent folks from using a bin near the front when seated in back). As people work their way on and to the back, the flight attendant in the back slowly works their way forward as those folks take their seats.

I think I recall a study where a boarding method scattered throughout the aircarft was the best, but I still hold out hope for my idea. . .

Posted by: Jim Hausch | February 10, 2010 1:17 PM    Report this comment

I fly over 100,000 miles on commercial carriers a year for business. I am also a Commercial pilot. I must honestly say the majority of long, sluggish lines are the result of changeable TSA procedures (sometimes radically different operating procedures in other countries with their own brands of security screening) and airport authority poor planning. As for the angst about boarding, everyone deserves the right to fly the friendly skies without feeling the enraged eyes of the person in back of them boring through their skull during bag stowage. Some people are handicapped, arthritic, confused, afraid to fly or otherwise unable to board, stow and sit with enough speed to please the impatient. I have found that humor and honest efforts to help are better motivators than stony silence or angry comments. Oh, I have never had a fat captain butt in line ahead of me.

Posted by: Rose Bult | February 10, 2010 2:06 PM    Report this comment

Ah, the essence of the New Society minus courtesy...thank goodness there still are people that take a moment to remember to treat others as you would onto you. Makes use able to put up with the do onto others before they do onto you...

Posted by: Chuck West | February 10, 2010 2:48 PM    Report this comment

I'm with you, Ms. Bult. I would be interested to know if in the book 'Traffic' which I haven't read, a study was done on the lane closure ahead WITHOUT signs indicating the event, or of the driver's ability to see it. We all have the awareness of the need when merging on the highway, but not knowing what is required ahead to be aware of is something entirely different. It does sound like from what Paul said that having early awareness of the closure does not benefit the traffic flow, at least in this particular case. Unlike the straight-in royalty who disrupts the traffic pattern.

Posted by: Dave Miller | February 10, 2010 3:34 PM    Report this comment

The studies were done with various kinds of signage, including one that said USE BOTH LANES TO MERGE POINT and another that said MERGE HERE, TAKE YOUR TURN. Early merge experiments were also tried.

"The late merge," says the book, "compresses what may normally be thousands of feet of potential merging maneuvers into a single point. There is presumably no lane jumping or jockeying, as the flow or speed should be no better or worse in one lane or another..."

Bottom line: be a late merger.

Posted by: Paul Bertorelli | February 10, 2010 3:52 PM    Report this comment

Jones Loop Road in Punta Gorda, FL has 2 southbound lanes. Warning signs and later arrows painted on the road warned people to merge before a railroad crossing just before railroad tracks at the intersection of US 41. Those self centered people would go beyond that to crowd in. The highway departments solution was knock down barriers which people did. After a few weeks of replacing the barriers they gave up let let the self centered people win.

Posted by: Unknown | February 10, 2010 4:36 PM    Report this comment

So if each and every driver in the thru lane when confronted with the merging car at the end point allows that car entry, now I see how that can work. So it's a book on comedy?

I guess I hadn't considered the 'freedom of the commons' before - other than 'if everyone did as I did, we would hardly even slow down', of course.

It usually was 'do I want to have to ask/plead/demand! entry at the final pinch point From others, or get in early and allow the one car-per-car entry (made sense to me) To others in front of me. Guess in traffic, at least, if given the choice by signage, I'd rather be asked for a favor than have to ask. Think I'll get a copy of the book.

Posted by: Dave Miller | February 10, 2010 4:40 PM    Report this comment

This would be true for everyone if everyone understood it and filled both lanes. This all fails when someone does not want to do the "zipper". I am all for letting one car in from the other lane, not ten.

I am a Captain for a major airline. I hate having to but in line ahead of paying passengers. It goes against all the training my mother gave me when I was young. So, when forced to do so (due to no dedicated crew line), I always apologize to the person I am butting in front of. Then I try to get everything into the bins as fast as humanly possible. It is the same every time: Outer coat, uniform coat, and hat (with phone and watch in it). One minute tops.

Posted by: David Heberling | February 10, 2010 4:45 PM    Report this comment

I've always wondered why the airlines can't figure out how to board from back to front, or let the window seats on first. Seems like a problem a high-school kid could solve with a laptop! Though I suppose if they made it too easy and rational to fly commercial, we wouldn't appreciate GA as much.

Actually, USAirways does board that way. That is what the zones are all about. I would still appreciate GA anyway because the TSA makes the experience so excruciating.

Posted by: David Heberling | February 10, 2010 4:49 PM    Report this comment

Traffic's a great book. Vanderbilt continues to extend some of the ideas in there, in his blog: http://www.howwedrive.com/ and in columns in Stale, er, Slate. He's been in Duber & Levitt's Freakonomics blog also.

One of the most interesting things, and one possibly applicable to how we fly, was the counterintuitive news that people drive more responsibly and safely in more "hazardous" conditions -- for example, rotaries/roundabouts versus traffic signals or stop signs. He thinks it's the perception of risk, ameliorating complacency. Reminds me of what an old jumpmaster told me once: "A little fear is good, it gives you an edge. Too much fear is bad, it makes you freeze." (For more on fear and survival, Laurence Gonzales's "Deep Survival" is my book recommendation).

Flying on any airline is a miserable ordeal, and it's largely due to the payroll patriots at TSA. Unfortunately many people now "expect" that level of abuse and wouldn't feel safe if they weren't getting it! Anything I can get to in one day of flogging pistons, I don't take the mailing tube any more. At 140 knots I can usually beat the lines door to door these days, which is just sad. Lots of good people working there and the service they try so hard to put out is being ruined by factors out of their control.

Posted by: Kevin O'Brien | February 10, 2010 8:36 PM    Report this comment

Amen to that Kevin...

Posted by: Chuck West | February 10, 2010 8:45 PM    Report this comment

Here in Czech Republic, we have the so-called zipper method directly in the Traffic Law. Means, that being on a merging lane in a two lane merge, you are supposed to go at the very end and there join the through lane. Drivers in the through lane are obliged to let go one car from the merging lane per one car from the through lane. Works pretty well, because everybody knows their place in merging scheme and no unnecessary braking and waiting is requered. Well until some jerk joins the through lane early and does not want to let people merge at the end. :o)

Posted by: Jiri Hubka | February 11, 2010 2:44 AM    Report this comment

All this discussion reminds me of my first driving lesson in the then Drivers Ed so Dad (me cause I am working)can afford the insurance. As I approached the merge with a car full of students, the instructor's foot came down upon my accelerator foot, as we rocketed onto the Expressway...lesson learned in a way a teenager understood, of course that was the 70's.

Posted by: Chuck West | February 11, 2010 8:48 AM    Report this comment

Mr. Bertorelli, with all due respect, how do we know Mr. Vanderbiltís book is well researched? What makes him the ultimate authority? Who did these studies? Who paid for the studies? What assumptions were made?

The Conga line for aircraft going to LAX often begins forming over the Grand Canyon in Arizona. Paul, are you now going to tell me that you are serving the freedom of the commons more efficiently by butting into the conga line on short final to LAX in your acrobatic biplane, oblivious to that doddering 747 driver behind you that doesnít want to let you in? After all, youíre using up more of the available airspace that way? Sorry, but I just donít believe that everyone moves faster with late merging, and I contend that butting in on short final would rise to the level of criminal recklessness.

Posted by: Bruce Liddel | February 11, 2010 11:43 AM    Report this comment

Bruce, your comparison is not logical. There is no controller -- one with intimate knowledge of the ultimate destination and capabilities of each automobile, and with a bird's eye view of the overall traffic situation -- organizing and directing drivers on the street.

Posted by: Mark Sletten | February 11, 2010 11:51 AM    Report this comment

Bruce,

Shame on you for throwing out such an obvious red herring. Comparing a controller-managed traffic flow with a self-arbitrated one (road driving) is an apples and oranges comparison.

My take-away from Paul's post is that the most efficient way to move traffic is often counterintuitive, and everyone would be better off if they understood the most efficient way (education issue, not safety issue) and followed it.

Posted by: Guy Hutchison | February 11, 2010 12:09 PM    Report this comment

Whether the controller is a human or the planned ahead road signage I think is really moot. Bruce and the rest of us live in the real world where this whole scenario is predicated on exquisite cooperation from all the cars in the play. The book is very mechanical and detached in its process and overlooks that very important caveat of mechanized behavior from individuals for the freedom of the commons. Works on paper, so what. If everyone accelerated at the instant moment the light turned green, I mean all at once, we would all go quicker and serve the common good better, too. Help the envoirnment, ... try it and see what happens.

Posted by: Dave Miller | February 11, 2010 12:25 PM    Report this comment

It amazes me that most of these comments are about the lane merge issue, but it shouldn't. The idiocy we have to put up with to get on an airplane and fly within our own country has become routine to the majority of Americans. And that's just wrong. Even the "give up and go along" crowd knows deep down that TSA's security puppet theater is just for show. What happened to courage and common sense in America? Why have we given up our rights for some illusory feeling of "safety"? Don't get me started on the cost/benfit of millions of hours and billions of dollars wasted because we lost 3000 lives one day in September yet lose ten times that on the freeway every damn year and still let everyone who can fog a mirror get behind the wheel... and merge poorly.

Posted by: Chuck Leathers | February 11, 2010 1:19 PM    Report this comment

Using your own points, sir, about the TSA and poor drivers you have reinforced the points being made about the lane merging, all in the realm of common sense.

What slows down the lane merging, airport security lines, and the like? Varied levels of awareness in individual people the world over. Whether Fat Captains, Overhead Hogs, Poor Drivers or Isle Idiots everybody is different, many affected by Political Correctness, Tea Parties, biases and anger. You say where is courage and common sense? I say where is tolerance, cooperation and helpfulness. It's out there, just depends on your viewpoint, I guess.

Posted by: Dave Miller | February 11, 2010 2:12 PM    Report this comment

I'm a late merger. Good to see that there is science out there that vindicates my actions.

I believe there are generally two groups of drivers out there who are at least perceived to be the root of all evil. The "aggresive drivers" (us late mergers get lumped in with them). And the "slow pokes".

In my view, at least the aggressives generally are engaged and aware of what's going on around them. The slow poke on the other hand.... He's the guy that comes out of that merge and moves over to the left as the traffic begins to accelerate. He then proceeds to put along 3 or 4 abreast with a mile of clear road in front of him and 5 miles of bumper to bumper behind him that wont clear for hours.

Now who do you think is the real problem in this scenario, the late merger or the oblivious slow poke?

Posted by: Mike Wills | February 11, 2010 2:29 PM    Report this comment

Good grief, Bruce, where did you get the idea that anyone is advocating butting into final approach? The essay refers in general to human habits and behavior. Read the book for yourself then decide. I have no obligation to defend it.

One point you are missing is that the research he quotes is not theoretical lab research plotted on paper roads. It is actual data collected on real highways and thus accounts for how people actually behaved. It's my view that any thinking person would find this interesting.

But, ah...maybe not.

Posted by: Paul Bertorelli | February 11, 2010 3:35 PM    Report this comment

Apparently Vanderbilt advocates butting into queued traffic, which I believe is as unsupportable as butting into final approach. I do find Vanderbilt's viewpoint interesting, even if I can't buy into the explanation. I'm guilty only of being self-righteous in my skepticism. I'd like to see the data - perhaps it is flawed - lots of bad science out there - but I hesitate to purchase the book just to be disappointed. Lots of experiments yield misleading data if variables are not controlled and sample sizes are too small. You could flip a coin ten times and have heads every time. Not likely but possible, and it could easily lead to incorrect conclusions, despite the real-world nature of the experiment.

To those who reject my logic, and who feel my analogy is a red herring, consider this: in heavy traffic, if the vast majority of car drivers merged early, the cheaters would in fact be attempting to merge with a queue of traffic almost as orderly as ATC-directed air traffic. I believe the late merging itself represents the real bottleneck, precisely because it prevents the early-merge traffic from remaining orderly, forcing stop and go driving. This is precisely what would happen if someone butted into final approach. I believe that the "using all available lanes" explanation is the real red herring, which my analogy fairly thoroughly obliterated, even if some were offended by the obvious stupidity of butting into final approach.

Paul ignored all of my questions.

Posted by: Bruce Liddel | February 11, 2010 11:26 PM    Report this comment

Lo and behold, Vanderbilt himself wrote "I was not advocating a Universal Late Merge plan. There are circumstances where this behavior would actually make things worse." http://www.howwedrive.com/2009/02/24/merge-overkill

At saturation (like at LAX), must evidently be one of those situations where late merge makes things worse. That same "at saturation" is what I usually see, whenever 2 lanes become one, and late-mergers are in a hurry.

Evidently Paul missed that small but vitally important distinction.

Posted by: Bruce Liddel | February 11, 2010 11:52 PM    Report this comment

Re: "Apparently Vanderbilt advocates butting into queued traffic"

No, he doesn't. RTFB before you tell us what he "advocates," why don't you?

Re: "To those who reject my logic..."

Well, we're actually rejecting your logical fallacy: in this case, the musty old strawman. No offense, but your argument is with your imagination's version of Tom Vanderbilt, not with the real guy (who is, actually, only popularizing research that academic researchers did, much in the way Malcolm Gladwell does). Get the book from your library and see if you are still as cross with Tom after you've read him firsthand, not filtered through me or Paul.

Posted by: Kevin O'Brien | February 12, 2010 12:03 AM    Report this comment

As Kevin says, Bruce, do some actual reading here rather than, as you concede, being "self-righteous" in your skepticism. The nice thing about Vanderbilt's book is that it's richly sourced. One can certainly be skeptical of his research, but one might bother to actually examine it first.

And no, I did not miss the fine point. I quoted the work fairly here.

Posted by: Paul Bertorelli | February 12, 2010 5:34 AM    Report this comment

As Kevin says, Bruce, do some actual reading here rather than, as you concede, being "self-righteous" in your skepticism. The nice thing about Vanderbilt's book is that it's richly sourced. One can certainly be skeptical of his research, but one might bother to actually examine it first.

And no, I did not miss the fine point. I quoted the work fairly here.

Posted by: Paul Bertorelli | February 12, 2010 5:35 AM    Report this comment

Bruce,

Your argument: I didn't study Vanderbilt's research, review the data, or conduct any research of my own. Nevertheless, Vanderbilt makes incorrect conclusions.

Case in point: You said, '...if the vast majority of car drivers merged early, the cheaters would in fact be attempting to merge with a queue of traffic almost as orderly as ATC-directed air traffic...'

There are sooooo many things wrong with this statement.

1. You are building a hypothetical traffic situation from which to draw conclustions; Vanderbilt's research is based on real-world observation.

2. You again compare largely self-directed road traffic with ATC-directed aircraft. The ATC-directed pilots are TOLD when and where to get in line. ATC had de facto control of the aircraft: it controls speed, altitude and heading. ATC retains control over the airspace and runway making it impossible -- and illegal -- for another aircraft to enter the line without permission. None of this applies to road traffic.

3. The wording of the statement itself belies your bias and prejudice. People who merge early are simply 'drivers,' while those who merge late are 'cheaters.' There is, in fact, no law governing exactly when a merge must occur, so labeling late mergers as 'cheaters' is simply ad hominem -- another logical fallacy -- and demonstrates your inability to separate the idea of ATC-directed air traffic and self-directed road traffic.

4. I could go on, but it's time to go fly...

Posted by: Mark Sletten | February 12, 2010 8:16 AM    Report this comment

Dear Kevin O'Brien I didnít say Vanderbilt advocates anything. I said APPARENTLY he advocates something, and I wrote such based on what Paul Bertorelli wrote. A few minutes later I found this was not the case, and I posted again, to the effect that Vanderbilt does NOT advocate ďa Universal Late Merge planĒ. That should have ended all this nonsense, because Iím not arguing that a late merge can NEVER be better, only that AT SATURATION a late merge cannot be better for the common good. Vanderbiltís position was initially presented by Mr. Bertorelli with no key points at all, so it seems unfair of you to accuse me of ignoring key points in Vanderbiltís position (a strawman). Iíll probably read the book now, but since I donít have an issue with Vanderbiltís CLARIFIED position, Iím not cross with Tom, and I donít see how reading the book will change my mind about late merging in saturated traffic conditions.

Posted by: Bruce Liddel | February 12, 2010 3:55 PM    Report this comment

Mr. Bertorelli: We agree that it is nice when a book of research is amply sourced. You and I seem to still disagree about whether or not late merging is ALWAYS better. It doesnít look to me as though Vanderbiltís book is going to support your position. You omitted this fine point, but you didnít miss it? How is that a fair quotation of Vanderbilt's position?

Posted by: Bruce Liddel | February 12, 2010 3:57 PM    Report this comment

Dear Mark Sletten, Your summary of my argument is so misconstrued as to be laughable. It might be easy to refute an argument that I didnít make (strawman), but doing so doesnít refute my argument.

RE your ďso many things wrongĒ #1. Saturated traffic is hardly a hypothetical situation. It happens all the time. As a matter of fact, I do have real world observations of my own, which are no less valid than Vanderbilt's. #2. Fine, forget LAX. Would you butt-in on short final at a non-towered airport where the pattern was at saturation, or would you enter on the dogleg and then extend your downwind until abeam the last plane ahead of you Ė as I was taught? The same principles of order and cooperation apply. #3 in Kansas, there is also a ďNo PassingĒ prohibition on the approach to closed highway lanes ahead. An ad hominem attack is on the character of the person who has an opposing viewpoint. Your misconstruing what ďad hominemĒ means does not refute my statement in any way. #4 Please donít go on. Go fly Ė just please fly friendly.

Posted by: Bruce Liddel | February 12, 2010 3:58 PM    Report this comment

Bruce,

You keep referring to specific, hypothetical situations when the discussion was about merging in general. I can devise any number of hypothetical situations where late merging might not be the best choice and/or even illegal. In general, however, when there are no laws or signage governing where and when to merge (the vast majority of merge situations I've ever encountered), late merging is not only acceptable, it is demonstrably preferable according to the expert who has studied the data.

Your non-towered airport comparison is, again, apples and oranges. There are specific rules about where and when to enter the traffic pattern; typically everyone is in radio contact with each other; if the traffic situation in the pattern doesn't work out pilots are free to exit the pattern where and when they choose as long as they don't interfere with other traffic in the pattern. None of these factors apply in a road traffic situation.

Re ad hominem: By referring to late mergers as 'cheaters' you've applied a label with a connotation suggesting they are doing something wrong. In short you are implying late mergers are wrong without supporting your implication with logical argument -- a classic ad hominem argument.

Posted by: Mark Sletten | February 12, 2010 4:18 PM    Report this comment

Dear Mark,

I think we finally agree (at least to a point) but you arenít willing to stop arguing.

Evidently, no analogy will ever be perfect enough for you. It seems that you cannot think in the abstract, though I certainly donít intend that as a criticism.

As for the meaning of ďad hominemĒ please refer to Wikipedia. An ad hominem argument has the basic form: Person 1 makes claim X There is something objectionable about Person 1 Therefore claim X is false

I hope I never claimed there was anything objectionable about ďperson 1Ē. As far as I know, ďcheatersĒ are not making any claims about ďXĒ. Iíve merely stuck to my original assertion that in saturation conditions, late merging is not for the common good, and that there is something objectionable about those who engage in late merging when it is not for the common good.

Posted by: Bruce Liddel | February 12, 2010 5:16 PM    Report this comment

I would say that most of the late mergers are taking advantage of fact they discovered the first time they tried it. They got in front of an awful lot of people who merged early. The reason most people do not merge late is because they are afraid that no one will let them in and they will be trapped. This is reinforced by the number of cars that are always piled up at the last merge point waiting for some sap to let them in. Since the early merger cannot wait around and see what happens to the late merger, they do not see that no one gets trapped. Some sap always lets them in.

In reality, no one is a sap, they are just being courteous. If everyone new the rules and both lanes were full, I would be happy to do the "zipper" because that is the most efficient way to handle a lane reduction.

Posted by: David Heberling | February 12, 2010 7:50 PM    Report this comment

Paul, I agree with you totally.

Humans are a herd animal who like to wait in line.

As you know I am an airline captain who is supposed to go the the head of the security line in order to make sure that I don't have anything I could use to take control of the aircraft. When I get there I grab two bins,step to the side, get out my computer,remove shoes, jacket,hat and cellphone than go step over to the X-Ray machine where I usually find the belt running with no bags going through while some passenger gets ready. I am usually able to go through without causing any additional delays to the passengers in line.

As far as the traffic merge is concerned.I am one of those guys who uses all available traffic lanes and will merge as late as possible. If I get to the front and find that early mergers are not letting late mergers in I make a point of letting two or three late mergers in.

Keeping the line moving is courteous.

Creating delays is rude.

Posted by: Thomas Witherspoon | February 13, 2010 12:44 PM    Report this comment

Bruce,

Saying you 'never claimed there was anything objectionable about person 1' is bit insincere, isn't it? Any reasonable (and honest) person reading this thread would make the obvious leap of logic that those arguing for late merging engage in the practice.

In arguing your position, you referred to those who choose to merge late as 'cheaters,' a term which was clearly intended to cast me and my argument in a bad light. After all, cheaters can't be trusted, right?

If you don't like describing such a debating tactic as ad hominem, how about sophomoric?

Whatever you want to call it, sir, I find it difficult to debate someone whom I feel is -- intentional or not -- arguing in bad faith. As such, I believe this is where it ends for me.

Posted by: Mark Sletten | February 13, 2010 5:51 PM    Report this comment

Which works totally against and is in opposition to what Paul's opinion of the book states on merging. Oh, and also could be construed to be rudely creating delays.... Wow.

Let's face it - or not - humans are individuals first, aquiesing to being herded second, and will seek their interests just like the good 'Captain' so eloquently stated that he does, and how splitting hairs like others are arguing always ends up a wash. Enjoying the book, thanks for the suggestion to Paul.

Posted by: Dave Miller | February 13, 2010 10:00 PM    Report this comment

This was supposed to be in first - 'If I get to the front and find that early mergers are not letting late mergers in I make a point of letting two or three late mergers in.' Sorry 'bout that.

Posted by: Dave Miller | February 13, 2010 10:04 PM    Report this comment

Dear Mark,

There was no Ad Hominem attack. In my previous post, "Person 1" = Mr. Vanderbilt; you must have thought "Person 1" = you. In my mind, "X" represented Mr. Bertorelli's abbreviated summation of Mr. Vanderbilt's position regarding late versus early merging. You evidently thought ďXĒ represented your personal position on the subject.

You think I personally attacked your position (as distinct from Vanderbiltís), by labeling you as an assumed ďcheaterĒ. I labeled late-mergers who violate no-passing zones in saturated merge conditions as cheaters in general, not you specifically. Do you see why I was confused? I donít feel that anything about you personally reflects adversely on your position on late merging. Your arguments (as far as I am concerned) succeed or fail on their own merits. I have no idea how or if your position differs from Vanderbiltís.

Note that an Ad Hominem attack is not prima facie logically fallacious (wrong on its face). You are welcome to attack me or my arguments in any way you like, subject only to the rules of posting on this website.

I am sincere, and please note that I have altered my position somewhat, in light of new information from Mr. Vanderbilt's website, so Iím really unsure how much we disagree anyway. If you canít change your mind, you canít change anything.

If you need to have the last word, just say so. If you really want enemies, I choose not to be one of them.

Posted by: Bruce Liddel | February 14, 2010 12:14 AM    Report this comment

OK, I've changed my mind and therefore in the future I will charge up the lane that has to merge. I will pass on the right (if that's the merging lane) and exceed the posted speed limit if necessary to expedite traffic flow. And, at the last moment I will force my way in unless some nice guy happens to be at the merge. I will trade paint with anyone who won't let me in. When I brake out of the merge I will feel really great that I have managed to improve my postion on the road while doing so much good for the other less agressive drivers. Wow guys, I feel better already! The heck with the airplane. I'm gonna get in the Mustang and head out to the interstate!

Posted by: Unknown | February 14, 2010 8:17 AM    Report this comment

"Probably works better in Indiana and Florida than on the approaches to the GW Bridge..."

Funny thing is, Paul, one of the most orderly mega-merges I've ever seen, and I experience it frequently, is on the GWB where southbound Palisades Parkway traffiic flows through something like eight tollbooths and then has to constrict to two and sometimes just one lane onto the actual bridge approach. It's amazing how well the "nasty New York/New Jersey commuters" of urban legend handle the complex chain of priorities and merge with each other in the proper order.

For that matter, the rudest traffic I've ever experienced is in the after-you-Alphonse heartland: Detroit.

I'm also amused by how many of your commenters wax wroth without ever having read "Traffic" (which I have).

Posted by: Stephan Wilkinson | February 15, 2010 8:07 AM    Report this comment

You youngsters won't remember, as I do, of airliners full of people around WW2 time, taking off with standing passengers, and then some kid with a guitar would stand in the aisle and play it, and the entire planeload would erupt in a sing-along.

Posted by: van cloud | February 15, 2010 9:13 AM    Report this comment

Late merging favors the minority that are merging late. The effective capacity of the highway is still determined by the bottle neck. Alternating merging is best, provided both lanes can maintain the same speed, the required spacing is there, and cars accelerate quickly after merging. Of course, that never seems to happen - I say more common is the early mergers close ranks to keep a small distance in front of them as defense against late mergers and this drives traffic to a stop and go pace. Trucks have a vested interest in blocking the late merging lane as they often cannot accelerate or brake fast enough to keep a narrow gap to the next vehicle. The really odd behavior is once slow, traffic takes forever to pick up speed again - even with wide open space ahead. It would be much better if cars accelerated as fast as possible until they were at least 10 seconds behind the car in front of them clearing a bottleneck. Watching people move in crowds is interesting, especially around constrictions like doors, escalators, etc. Late merging here is wildly unpopular in most cultures...

Posted by: Eric Panning | February 16, 2010 2:46 AM    Report this comment

Late merging favors the minority that are merging late. The effective capacity of the highway is still determined by the bottle neck.<<

You base this conclusion on what data?

Posted by: Paul Bertorelli | February 16, 2010 8:44 AM    Report this comment

Mr. Liddell's argument doesnt fly because it assumes that the "cheaters" create the bottleneck when the merge reaches the "saturation point". The argument falls apart because every driver has his or her own definition of what the "saturation point" actually is. When traffic is creeping along at walking speed at a merge and there are numerous cars at that speed that feel like they need 5 car lengths of free space in front of them because thats their definition of "saturation" and safety, they are the ones creating the problem, not us "cheaters". I can safely enter in front of them and reduce, not increase the congestion.

The comparison with arrivals for air traffic is nonsensical. There the saturation point is very well defined by ATC seperation minimums.

Mr. Wyant, nobody is advocating reckless behavior here and nobody here is suggesting the sort of driving you describe.

I'd love to hear what you guys think of lane splitting motorcycles in congested traffic. But I think I already have a pretty good idea.

Posted by: Mike Wills | February 16, 2010 10:51 AM    Report this comment

I'd love to hear what you guys think of lane splitting motorcycles in congested traffic. But I think I already have a pretty good idea.<<

Oh, man, you hadda go there? Since you did, I'll just say lane splitting is California's gift to motorcyclists. And drivers for that matter. Most drivers seem okay with it there because it's accepted practice. In my experience--limited--the occasional moron will try to whack you with a mirror, but most people get it.

Try it elsewhere and they tend to freak. Only legal in California, anyway. It is practiced in Europe, especially Italy, where motorcyclists and scooters use it aggressively. On the autorstradas, if you approach a car's left bumper from the passing lane, it will move right and let you pass in the split lane. Unless it's an Austrian driver, where they don't seem to practice it.

Posted by: Paul Bertorelli | February 16, 2010 11:50 AM    Report this comment

I get your tongue and cheek, Mr. Wyant, particularly if it's a classic Mustang.

Even tho I have now read thru the book offered, I still look for the glorious day when, whilst driving my mini-motorhome into a merge point, I am actually allowed entry into the mainstream common, to smoothly take my place among the marchers, as in the brilliant German movie Metropolis of old. Ah, but to dream..

Posted by: Dave Miller | February 16, 2010 12:43 PM    Report this comment

Thanks, Dave It's a retro Mustang though....sorry. I'm afraid Mike missed my attempt at a little humor.

Posted by: Unknown | February 16, 2010 1:20 PM    Report this comment

Paul, if cars merging late are passing cars that already have merged then they are A) in the minority and B) Moving ahead of cars that were ahead of them If every one is going the same speed and "zipper" merging then there really isn't a late merge. What is your view on traffic control lights at entrance ramps? Wouldn't this be an inefficient merge? Is the traffic science behind these all wrong?

The loading of a section of highway is determined by the density of traffic and the group velocity. The safe capacity is determined by optimal speed and following distance. You can pile the cars into the bottleneck any way you want, but you need to get them moving efficiently. For example, a 2 lane highway with 55 mph traffic at 50% of capacity should be able to merge into a single lane and continue at 100% capacity at 55 mph. However, that never happens. A) Drivers slow down bc of any change (As Tom V points out) B) Late merging traffic slows down bc of the risk of hitting the barriers C) now everyone is going slow...

You can see similar dynamics in traffic around carpool lanes. It would be most efficient to merge late from the carpool lane to the non-carpool lane when exiting the highway. In practice, it risks being hit from behind. This and the dynamics of merging into the carpool lane keep the speeds lower than the volume would suggest.

Posted by: Eric Panning | February 16, 2010 1:56 PM    Report this comment

What is your view on traffic control lights at entrance ramps? Wouldn't this be an inefficient merge? Is the traffic science behind these all wrong?<<

No. Ramp metering has been universally shown to increase throughput to the maximum capacity of the road. In one study Vanderbilt quoted in Minneapolis, the ramp metering was removed and congestion increased.

But the dropped lane merge is a different scenario because the driver is confronted not just with a single choice, but a range of continuous choices.

The data showed that a later merge kept the mainstream flow moving more quickly--about 15 percent more throughput--because all of the available pavement was being used.

Implicit in study was that if *everyone* merged early, the main flow slows earlier and has many more gaps in it. This effectively means that less of the pavement is being used and thus the overall throughput is less because the entire stream slows more and earlier. In this case, the bottleneck isn't the main controller.

So it's not just the bottleneck that determines efficient flow, but what happens behind the bottleneck--the decisions drivers make.

Intuitively, this makes no sense because you would naturally assume that with no metering light or a traffic cop, chaos would ensue. The suprise was that it did not and efficiency increased. So late mergers help not just themselves, but the entire group. (Conceding that this will not be true in all scenarios, but can be true in some.)

Posted by: Paul Bertorelli | February 16, 2010 3:05 PM    Report this comment

What is your view on traffic control lights at entrance ramps? Wouldn't this be an inefficient merge? Is the traffic science behind these all wrong?<<

No. Ramp metering has been universally shown to increase throughput to the maximum capacity of the road. In one study Vanderbilt quoted in Minneapolis, the ramp metering was removed and congestion increased.

But the dropped lane merge is a different scenario because the driver is confronted not just with a single choice, but a range of continuous choices.

The data showed that a later merge kept the mainstream flow moving more quickly--about 15 percent more throughput--because all of the available pavement was being used.

Implicit in study was that if *everyone* merged early, the main flow slows earlier and has many more gaps in it. This effectively means that less of the pavement is being used and thus the overall throughput is less because the entire stream slows more and earlier. In this case, the bottleneck isn't the main controller.

So it's not just the bottleneck that determines efficient flow, but what happens behind the bottleneck--the decisions drivers make.

Intuitively, this makes no sense because you would naturally assume that with no metering light or a traffic cop, chaos would ensue. The suprise was that it did not and efficiency increased. So late mergers help not just themselves, but the entire group. (Conceding that this will not be true in all scenarios, but can be true in some.)

Posted by: Paul Bertorelli | February 16, 2010 3:06 PM    Report this comment

Ray, given the comments from some on this thread, your post could have been taken either as tongue in cheek humor or been completely serious.

Ramp lights... Since Caltrans just installed them at the freeway on ramp I use coming to work they've taken what used to be a pretty easy merge and screwed up not only the ramp but also traffic on all of the surface streets that feed the ramp. So based on my admittedly limited sample, yes the traffic "science" is completely screwed up. I cant see how adding additional bottlenecks solve any problem. Again, in my case they dont. I hit the first traffic jam at the on ramp and the second 2 miles down the road at the merge. I liked it better when there was just one traffic jam.

Posted by: Mike Wills | February 16, 2010 4:00 PM    Report this comment

I heartily agree with one of the posts that there are timid, aggressive and courteous drivers. It seems that the meaning of 'merge' got lost in the discussion, and while driver behavior is an outcome, I think road design is a huge player as well. I've lived with some really stupid forms of 'merge,' including a stop sign at the end of an acceleration ramp. Surprise!!! Likewise, aircraft boarding and baggage stowing could take some revision as suggested. If turn signals at the merge are a form of courtesy and consideration I'm all for it. Too many play 'guess my intentions' with an auto to take it lightly.

In Germany there are two rules that I find liberating: First, the left or priority route is for passing, and if you cannot keep up, get into a slower lane. It's the law. Second is the concept of priority route - designated with a little diamond at traffic control signs - that indicate who had the right of way when it might be ambiguous. Those resolve a lot of hesitation along with intelligently designed roadways, at least on the autobahn. The flip side is that traffic will come to a standstill if there is moisture anywhere nearby. Perhaps exaggerating a bit, but I'm told it's in their driver certification, which isn't given lightly.

Posted by: Thomas Connor | March 25, 2010 11:03 PM    Report this comment

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