Bryan Caplan  

Terror Profiling

The Autobiography of Malcol... EconLog Book Club Round-up:
Two quick replies to Garett:

1. If terrorists were as flexible as he suggests, airport security would be useless.  Terrorists would simply switch to one of the countless undefended targets: trains, sporting events, malls, etc.  Profiling doesn't have to be perfect to be extremely effective, and I don't see that Garett's counter-examples show otherwise.

Slightly different perspective: Right now, we use the profile, "Terrorists love targeting air travel."  Given the paucity of U.S. soil attacks in the last eleven years, we can conclude that either (a) this profiling works well, or (b) there's little threat to begin with.

2. The original issue was whether free-market airport security would be more convenient.  A more elegant way to make my original point: When security gives you an easy time, do you become (a) more reluctant to use that airport, because you're afraid their lackadaisical attitude makes terrorism significantly more likely, or (b) less reluctant to use that airport, because you value convenience and aren't seriously worried about terrorism? 

My sample could be biased, but everyone I've heard or overheard in the last ten years has reaction (b).  If you were running a profit-maximizing airport, wouldn't (b) be the reaction you'd aim for?

Of course, if seemingly asinine airport security measures are really saving lots of lives from terrorist attacks, there's a big offsetting factor: making life convenient for passengers today risks massive negative publicity and low ticket sales tomorrow.  Yet insofar as airport security is basically just security theater, you should conclude, contra Garett, that free-market security would be markedly more convenient for (most) air travelers. 

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COMMENTS (10 to date)
Daublin writes:

I believe to run a profit-maximizing airport, you'd try and convince everyone that air travel is safe. You'd loudly advertise the long safety records of air travel, and you'd quiet down the security theater.

We're just speculating, though. The more predictable outcome of privatization is that different airlines would try different things, and some of those things would work better than others. Some would have more theater, some would have less, and all of them would trend toward security that is actually effective.

Personally, I still hope for the emergence of Glock Air, the airline that hands you a firearm as you board.

Doug writes:

Complete absence of government would probably mean that flights would start flying pilotless. Auto-pilot already does everything, has an excellent safety record and pilots make up about 20-25% of the cost of airlines.

Sure a lot of people would loudly proclaim that they'd never fly a plane without a human. But once their friends and family do it and it becomes viewed as normal and safe it won't take very long for them for those flights that cost a quarter less to start looking pretty attractive.

Once planes are pilotless the whole concept of a plane as a terrorist target is pointless. You can't hijack a plane that only runs on auto-pilot any more than you could hijack an elevator.

You might still get bombers, but there'd be nothing particularly special about planes versus other crowded public venues. In which case security would boil down to simple checks found at stadiums and amusement parks. Look through your bag to see if there's an obvious explosive device. Good go ahead through.

Methinks writes:

What were (and still are) the odds of dying in a terrorist attack on an airplane before the beefed-up, post-911 security? 1 in 25,000,0000? Let's do that math. Let's see...carry the one..and..uh, yeah, that would be pretty much not very different from zero.

So, yep, I vote for not being forced to get undressed, treated to a dose of radiation and then fondled by a posse of thieving thugs on my way to the air machine.

The odds of dying in a non-terrorist plane crash aboard an airline with an excellent safety record is 1 in 9.2 million. Given the overreaction to 9/11 to reduce the probability of a near-zero probability event, maybe we should just ban flying altogether in case anybody gets hurt.

David S writes:

I think the most salient question is: "How many attacks have been thwarted by the current government security levels at the airport, vs how many attacks got through?"

I looked through "the google", and my answers to these questions are:

How many attacks have been thwarted by the current security levels at the airport: 0

How many attacks got through (successful or foiled by passengers): 2

It doesn't look like airport security actually helps that much. A lot of attacks are thwarted by normal law enforcement personnel, of course.


Chris H writes:

One of Garrett's complaints about profiling is that it's ineffective. However, this is a non-sequitur given that the argument is that free market airports might engage in "security theater." The actual effectiveness of a technique is irrelevant compared to whether the average person feels safer. Now irrationality tends not to persist in the face of high costs (which is an excellent argument against the idea that free market airports would persist in invasive and annoying security checks over the medium-to-long term) so we would only expect people to reward a more rational "check regardless of profile" procedure if there was a major cost to the "check based on profile" procedure. That cost would be in a higher number of terrorist successes. Let's do some math here.

I'm going to make some generous assumptions about the anti-profiling position. First, let's assume that non-profiling security checks catch terrorists 90% of the time while terrorists are always able to dodge the profilers creating a 0% chance of catching a terrorist. Second, assume that all the attempted terrorist attacks in the US since 9/11, 50 in total as of April 2012, would have focused on the airlines in a scenario of free market air travel. Furthermore, I will be assuming that only the security checking procedure determines whether or not the terrorists get caught or not (most were caught by police work long before the plot was launched which would only strengthen the argument that choosing a particular security system at airports is either irrelevant or nearly irrelevant to safety). Now, in 2011 and 2012 there were about 9 million domestic flights per year. I will be assuming a lower average when we take the entire 2001-2012 period into account, say about 8 million flights a year.

So under there conditions, what is the effect on safety of using a profiling or not profiling security system? For those interested in checking the math, [(1-r)X]/Y where r is the rate of intercepting terrorists, X is the number of terrorist attempts (given earlier) and Y is the number of airline flights from 2001 to the present (going with 8 million per year average). Under the non-profiling system with the 90% of capture we would see a chance of 1 out of 17,600,000 of a given flight you are on experiencing a terrorist attack. With the profiling with the 0% of capture we see a 1 out of 1,760,000 chance. Ten times more likely yes, but still pretty small. Now let's take this further. Say the average person would be willing to pay/forgo $10,000,000 to avoid being in a terrorist attack. Given that terrorist attacks are not necessarily successful when they get on the plane nor are they by necessity fatal, $10,000,000 to avoid the risk and hardship involved seems reasonable. Under the "check regardless of profile" scenario let's say your chances of being checked are 1/20 and under the "check the profile" scenario your chances of being checked are zero as long as you're outside the profile but 100% if you fit the profile, which one out a hundred people fit the profile. Let's then suppose that the average person would be willing to pay/forgo $150 to not be checked (which seems reasonable given the humiliation, the invasion of privacy, and the fact that you might have to be more careful in what you pack). So under these conditions which of these scenarios is best for the individual flyer?

Under scenario "check regardless of profile" the chance of an attack multiplied by the value of not being in an attacked is about 57 cents. Under the "every terrorist gets through/profile" scenario that's upped to $5.70. So the more effective procedure on average saves customers $5.13 from the threat of a terrorist attack. But that is actually less than the cost incurred from the checking? Given the average cost of $150 per security check then multiplied by the chance of that check happening on any given trip to the airport, the average cost for the non-profiled 99% of the populace is zero in the profiling airports, but $7.50 in the non-profiling airports. The profiled minority wins big in that bargin, but the non-profiled majority actually loses even though the chance of a terrorist attack has been cut to one tenth of the chance with profiling.

In reality, I've used highly unrealistic assumptions in favor of the non-profiling high security route. The real chance of a terrorist attack successfully getting on a plane is FAR lower than what I sketched out meaning the savings from reductions of terrorist attacks that make it one the plane are significantly less (keep the same assumptions and plug say 10 into X to see what I mean). Furthermore, even the number of terrorists that make it to the airport or that even plan on using planes is significantly lower than I used. The result is that the benefits of profiling for the non-profiled majority are even more lopsided even assuming that terrorists ALWAYS are able to get around profiling procedures.

The one factor I ignore is the potential that people will gain a greater feeling of safety with better non-profiling procedures, but in order to assume that I would have to assume that people take the time to learn what is effective in airline safety. If they did that then they are likely to learn that the chances of a terrorist attack are so low that no intrusive security procedures are really that worthwhile. Of course that's the real lesson to take away. The chances of a terrorist attack are so low that even frequent flyers have near zero chances of being on a plane with a terrorist attack occurring (specifically, given that only 5 flights including on 9/11 have had terrorists actually make it aboard in US airspace since 2001 your chances of being on a plane with a terrorist attack while doing 1,000 flights in that time frame is a little over half of one hundredth of a percent). It's easy to see scenarios where it's not worth it to passengers to have the added safety, and irrationality tends not to last too long in the face of real costs with few if any benefits. Free markets will thus really tend to decrease all the invasive security measures, though profiling may last longer than non-profiling (especially if the chances of catching a terrorist are fairly close in either case which seems more likely than my 90-0% divide).

blink writes:

Point #2 sounds like a knock-down argument. I am surprised I have not heard it before. Anyone who wishes to dispute such obvious and overwhelming revealed preference data has got a long uphill battle ahead. The only reasonable reply I can imagine is: No, no, no airport security is not about protecting air travelers but the people who live/work at potential targets.

Peter H writes:

Re: Daublin,

No way would I ever fly on Glock Air, or even out of an airport serviced by them. Nothing to do with whether it's a good or bad antiterrorism policy, everything to do with some idiot's toddler playing with mommy's new toy and blowing my brains out. Or the drunk and belligerent guy who's gonna miss his connection because we got waved off of landing due to a runway incursion and have to wait 45 min for another slot.

Guns can be handled safely, but they are not inherently safe items. I would expect all or almost all airlines to maintain strict "no gun" policies (easily enforced by simple metal detectors), and would never fly on an airline that permitted firearms. This isn't a government intrusion thing. It just happens that my consumer preference would be anti gun-on-plane, and I'd seek businesses who would accomodate that preference.

Glen writes:

Profiling would be implemented very differently in a so-called free airline security system vs. one run by the government.

Rather than profiling based upon appearance, race, sex, age, etc., free-market airline security would profile based upon customer value to the enterprise. Top-tier customers would enjoy the best (meaning least intrusive) security. Airlines could rely on their long-term relationship with these customers and vast quantities of data about their habits and personal lives to reduce (or even eliminate) physical screening.

While potential terrorists could defeat this system, too, the cost in time (multiple years) and money ($100K to $1M) would likely be prohibitive. And such a system would properly place the cost burden on terrorists vs. airline passengers.

The TSA is attempting to implement a rudimentary form of this type of profiling with their TSA Pre✓™ program. However, it still relies heavily on randomized intrusive screening and traditional government security clearance (and identity verification) protocols rather than customer value and long-term behavioral information.

However, true customer value screening is already fully implemented in private aviation. Passengers flying on charter, fractional, corporate or personally-owned aircraft from airport FBOs are not subject to any physical screening whatsoever.

John T. Kennedy writes:

I conclude there is little threat to begin with because I can't believe there is a viable dangerous enemy so inflexible as to insist on attacking planes when there are countless soft targets that would serve their purposes just as well - especially since the supposed enemy in question is known for hitting soft targets in other places.

I'm not saying that there will be no more victims of terrorism on American soil, just that on the whole terrorism doesn't rate very high on a list of threats to American lives. Buckling your seatbelt will do a lot more to protect your life than hardening airports.

Kyle writes:
2. The original issue was whether free-market airport security would be more convenient. A more elegant way to make my original point: When security gives you an easy time, do you become (a) more reluctant to use that airport, because you're afraid their lackadaisical attitude makes terrorism significantly more likely, or (b) less reluctant to use that airport, because you value convenience and aren't seriously worried about terrorism?

I don't believe that a free-market airport security would be more convenient. Right now airports everywhere are taking care of threats and security just fine. Sure 9/11 was horrible, but they have definatly stepped it up since then. (a)I have been to the airport numerous times and walked through security like nothing, but terrorism is not going to be more likely. We have the machines now that scan bodies, and if you opt out of that you get a full pat down. Also, a few months ago I was waiting in line to go through security, and one of the TSA employees walk over to me and told me to hold out my hands. She used a pad to take some kind of sample from my hands and put it into a machine, which scans for bomb residue or materials used to make bombs. I was very suprised she profiled me out of everyone to pick. I'm a six foot Caucasian male.. So security doesn't just profile a certain race, they go for anyone!
Anyway free market airport security seems due-able, but its just not needed at this point.

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