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What Medical Tests Should Teach Us About the NSA Surveillance Program
First time accepted submitter Davak writes "In many ways finding the small amount of terrorists within the United States is like screening a population of people for a rare disease. A physician explains why collecting excessive data is actually dangerous. Each time a test is run, the number of people incorrectly identified quickly dwarfs the correct matches. Just like in medicine, being incorrectly labelled has serious consequences."
the NSA is not concerned about infringing on people's rights and civil liberties. if we are going with medical analogies, i think the NSA would rather amputate than treat an infection.
Anons need not reply. Questions end with a question mark.
After glancing over the summary, I'm fine with doctors are experimenting on terrorist dwarves.
That the NSA is not specifically looking for terrorists, although that is the convenient excuse. They are looking for all sorts of things, and that is why they are collecting everything. They are listening in on foreign diplomats to see what they are up to, they are eavesdropping on foreign corporations to give US companies an advantage in trade deals, they are digging up dirt on political enemies and protesters, and they are checking up on reporters to help keep them in line, and they are especially looking for whistle blowers who might throw some light on what they are doing with our tax dollars. All of these activities have been reported, so it doesn't take much imagination to realize they are collecting everything they can on purpose and for numerous reasons, most of which are not to the benefit of the American people. If the intention was to help the American people, they would be putting all that computing power into bioinformatics to cure cancer and other diseases that kill half a million Americans a year.
A brain is a terrible thing to waste... Mind? That's debatable.
So you have no test and just let the virus spread?
You extend the analogy too far. In fact, the analogy in TFA, while interesting, has limited relevance. Yes, the danger and destructive effects of false positives are important in both medicine and national security, but where TFA mentions (almost in passing) that "The balance between privacy and security is always difficult", it sidesteps the simple fact that this surveillance is about neither. It is about control.
Let us not fool ourselves that the US (or any other) government is actually likely to prevent all (or any) acts of terrorism with these efforts. We have recent proof otherwise. Our various governments have simply seized on this supposed threat as a means to exert control - for no other reason than because they can.
No, because the point is that the false positive results lead to more invasive tests (which in themselves may do harm), over-interpretation of other physical signs, worry etc.. The parallel with terrorism is that people end up on no-fly lists, get invasively searched and questioned, might get turned down for jobs or credit etc.. The uselessness of screening tests for low prevalence diseases is well known in the medical world, which is why tests need to be targeted to a high-risk population to have any value.
As your elected representative let me enlighten you as to why you voted for me rather than the other guy:
* I made good, powerful speaches. I went to some classes to help with this, it is more important that I dress in a good suit and have a strong voice than what I say makes sense.
* I avoided checking facts when making opinions. If you know the facts you realise that things are not black & white, but to express that makes people think that you are a ditherer, that you don't know what you stand for. Who wants a politician who, when asked a question instead of saying ''yes'' or ''no'' says something long and boring that starts with ''It depends'' ?
* Most of you don't look at the facts, you work on gut feeling and gross extrapolation. You remember that story in the local press last week about the thief from out of town who had green eyes, blond hair and a limp ? Yes: you are quite right to know that everyone from out of town with blond hair & a limp is a good for nothing crook and we don't want people like that round here!
* You people just want to be safe. You don't care what happens to out of townies, how hard we make it for them; or even foreigners -- some of who have a skin of a funny colour. They just don't matter!
* You don't really know what safe means, but are happy if you can still watch TV and drink beer when supporting your team. My predecessor did not do anything to make you realise that you can do something else, neither will I --so you will vote for me next time.
* In order to get on the short list for election I had to sign up to what the party says. They won't listen to a newbie like me, if I ask questions there are plenty of others to choose from who do what the party bosses say.
* Do you know how much I got in ''research grants'' and travel ''expences'' from the large corpotations? To say nothing about my fee for 2 days work a year as a consultant. I must not upset them by saying something that upsets them. All that money buys a lot of publicity as well as letting me buy that new yacht..
* I have a good friend who knows people, (I don't want to know why they are), but I got warnings of the other guy's plans and it was mighty useful when his campaign manager was caught in bed with that young ... that no one had seen before
So you see, I would be really silly if I upset the status quo and made you think for yourself.
When you screen huge masses of people needlessly, almost all to all of your hits are going to be incorrect. Additional testing of these false positives are harmful. Biopsies, radiation, no-fly lists -- harmful.
Nobody is saying that we should never wiretap if we have evidence. That's testing a small population. The problem here is that we are wiretapping everybody to attempt to find evidence.
Where's the "-1: conspiracy theorist" option?
Let us not fool ourselves that the US (or any other) government is actually likely to prevent all (or any) acts of terrorism with these efforts. We have recent proof otherwise.
It's no longer "recent" by media standards, but the (second ;-) attack on the World Trade Center is an excellent example. Much of the news coverage of the event is still available online, and if you dig it up and look at it, you'll see that several things stand out. One is that the US authorities were totally taken by surprise, and didn't have any idea what was happening until after the second tower was hit. However, it became clear in the first several hours that they'd decided who to blame. The reports from everywhere were full of "Al Qaeda" and "Osama bin Laden" (often badly mispronounced ;-), despite the obvious fact that they couldn't have collected the evidence in such a short time.
Over the following weeks and months, it also became clear that their ignorance was pretty much self-imposed. They had been warned about the specific perps by various other countries' security folks, and chose to ignore the information. This was in part due to a serious shortage of Arabic-speaking translators in the US military/security agencies. This was in turn due to their mistreatment of Arabic speakers, which the US has millions of. If you look into this, you'd probably also conclude that anyone fluent in Arabic would have to be really stupid (or suicidal) to volunteer for a translator job in those agencies.
The most parsimonious theory explaining this is that the US government isn't particularly interested in finding and blocking terrorists; they are mostly interested in using such things as a way of instilling fear in the general population. With this understanding, the government's "anti-terrorist" activities make a lot of sense.
(And, of course, treating the US government as some sort of unified, monolithic entity is a major mistake. There are lots of people in various government agencies who understand the situation pretty well. But they're generally not the ones in charge. Or if they are, they also understand that it's all to their own personal benefit. Or they keep quiet because they understand how "whistle blowers" are treated, and don't want that to happen to them. But we may hear from them after they retire. ;-)
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
That's not the precise argument, at least in a medical context. If the tests themselves and the responses to false positive have no significant medical downside, that's one thing.
But, let's say we starting giving all women yearly mammograms at age 16. Now, while this might reveal a very tiny number of additional breast abnormalities (many of which won't be cancerous) it's going to expose a lot of women to increased amounts of radiation, and while that amount of radiation is slight, that is likely to lead to a measurable increase in rates of cancer. If you're causing more cancer than you're catching, it's a stupid test, right?*
In addition, the response to false positives needs to be taken into question. Further procedures have their own medical costs. If you have a high rate of false positives leading to painful and hazardous procedures, that cost, too, has to be weighed against the value of catching those cancers early. ... and I will stop here as the breast cancer analogy in particular is one I can babble on about for a very long time. (My mother is a breast cancer survivor, and was diagnosed fairly young, which puts me in a high risk category.)
* One could make the argument that this is a very tight analogy, as if surveillance is increasing hostility towards the government by US citizens, and towards the country overall abroad, we could be creating a worse situation than we're addressing. I think this is a pretty strong argument applied to some of our foreign wars.
When you screen huge masses of people needlessly, almost all to all of your hits are going to be incorrect.
Yes, this is something that apparently even most doctors don't understand. Suppose who had a simple problem like this:
1% of women at age forty who participate in routine screening have breast cancer. 80% of women with breast cancer will get positive mammographies. 9.6% of women without breast cancer will also get positive mammographies. A woman in this age group had a positive mammography in a routine screening. What is the probability that she actually has breast cancer?
The correct answer (calculated from Bayes' Theorem, or simple logic) is 7.8%. Most doctors cannot do this problem, and that not only get the answer wrong, but they often get it wildly off -- estimating the answer to be much greater than 50% (often 70% or so, probably from simply subtracting the two numbers).
If you don't believe me, have a look at this link. As the author says there:
usually, only around 15% of doctors get it right. ("Really? 15%? Is that a real number, or an urban legend based on an Internet poll?" It's a real number. See Casscells, Schoenberger, and Grayboys 1978; Eddy 1982; Gigerenzer and Hoffrage 1995; and many other studies. It's a surprising result which is easy to replicate, so it's been extensively replicated.)
The author here is being generous. I looked at these studies years ago, and many of them show only 5-10% getting the answer to such problems correct.
And if this is true of physicians, it's probably true of just about anyone else who encounters a lot of false positives and isn't used to thinking statistically. That means most people are very likely to draw incorrect conclusions about the prevalence of something when the false-positive rate is high... making those using the methodology assume that (1) their methodology is better than it is, and (2) that with more "assumed positives" from incorrect logic, the incidence of whatever they're looking for in the population is higher than it is.