Let us extend the logic to 99.9% accuracy, and apply it to 50 mil PAX (aasumption that each airport entry is a separate event, i. e. X is not a terrorist today, but could become one tomorrow).

999 of 1000 terrorists, hijackers, etc. would be identified along with with 50,000 innocent PAX

2% of the people detained (140 detained per day)would be correctly selected and 1 terrorist incident could still occur.

I think we all know the answer to that. The screening circus,far more visible than Research and Development, makes a number of travellers and the majority of non-travelling people "feel" safe and gives them an illusion of security.

This thread has been moved to a new board recently setup in TravelBuzz to address security related topics:

Please use the link below to enter the new board:

http://www.flyertalk.com/travel/fttr...e=5&LastLogin=

Radiocycle
In The News Moderator

This thread makes me laugh. If we applied statistics and math to everything, nothing would ever happen..
would you get married? heck no, 50% fail
would you drive? heck no, too many wrecks
would you play the slots? heck no 98% lose.
would you smoke?
would you drink?
would you do anything?

Mathematicians love to make arguments with numbers, fact is, real life doesn't work that way. Gee wait, there have been no hijackings since the TSA took over..that proves things are safer, doesn't it! Eureka!

Holy Cow! I'm a mathematician so I thought I'd steer clear of this thread, but this post got my goat (whatever that means).

married - yes 50% is good odds at this

drive - yes, the % of wrecks is NOT "too many"

slots - sure I play, I count on losing though if you play long enough

smoke - I have, but I know the risk

drink - I have, but I know the risk

anything - yes, including die eventually.

Properly done, you can TRY TO apply math and statistics to everything. In fact one of the most fascinating and beautiful academic endeavors is to apply mathematics to understanding mathematics itself. (See Kurt Godel on this.)

The first post is self evident. A small incidence percentage appllied to a large universe generates many false positives. How can anyone dispute this?

Real mathematics works, false applications of it don't.

How many hijacks were there in the U.S. before 9/11?

It amazes me how little some people feel mathematics plays in their life when I look around and feel surrounded by it

Tazi said:
Depends on how far back you want to go. Lots of them up to 1992, most to Cuba. If anyone wants to read an extract that details a general history of aircraft hijackings since 1931, here is a pretty good one:

http://pegasus.cc.ucf.edu/~surette/hijacking.html

Then after 1992, I'm aware of one (a cargo plane out of Memphis) and then of course the big four.

Of course you are probably well aware my comment was a tongue-in-cheek one and was a bit like the comments made about how certain actions keep Elephants away and that the absence of Elephants (where none ever appear anyway) is evidence of the efficacy of the action. My point was that numbers often are used to prove points when they have no real relationship to reality. At the same time, I am smart enough to recognize that numbers can be important in our life. Have a stress free day.

Thanks, that was my point as well, perhaps not as eloquently said. The question is as you responded to the various scenarios, do we want to take the risks or not? It is probable that any system designed to capture criminals will result in "false positives." Some folks use that percentage as a basis for saying that the process should be eliminated. The question for me is, what are the consequences of no system and do the adverse consequences of that outweigh the "bad" within a system that has false positives. Again, some people have zero tolerance for false positives, others have zero tolerance for a system that allows more criminal acts. Problem is, those who espouse trashing the system have few if any alternatives other than, "I'll take my chances." Fine, but some of us don't want to take that chance. I'd rather have a slightly flawed system where the legal process can work out the details of the flaws rather than no system at all that invites more hijackings. Especially since the terrorists have made it clear that their intent is to do more of the same.

Actually, that is most of them up until 1972 not 1992. So, for almost 30 years, there were very few hijackings in the U.S. until 9/11. Well, I hardly think you can use the fact that there have been none since 9/11 to imply it is because of the search for pointy objects being carried out by the TSA since then.

I like how you selectively trimmed what I said to make it look like I said something else.

I didn't trim anything. You misquoted the article. Even after reading the whole thing and still not seeing where there had been hijackings to Cuba up until 1992, I did a search of the article. 1992 is not in it.



[This message has been edited by tazi (edited 01-26-2003).]

Thanks for this truly thoughtful reply. I guess that's it: some are hopeful the security will help and don't care about the intrusions, others aren't so hopeful and feel the intrusions a waste.

Maybe it is all about optimism vs. cynicism. I think I lean toward the cynical.

REALITY CHECK

The last time I looked, mathematics was an wxact science. Try this for exact. Question 1. Since the implementation of the TSA methods of screening, how many acts of terrorism have been attempted on our airlines? Answer 1. Pick any number. Question 2. How many acts of terrorism have been accomplished on our airlines in that time? Answer 2. 0 Now divide Answer 1 by answer 2 and you get 0%. And 0% is a very nice number.

MATHEMATICAL CHECK

Division by zero is undefined. You get no answer when you divide a number by 0.

[This message has been edited by tazi (edited 01-29-2003).]

1) There is no proof (proofs are very important mathematically. Have you ever done one?) that the TSA is the reason there haven't been any terrorist acts since 9/11. I have a rock that I claim keeps terrorists away. There is just as much specious evidence that my rock keeps terrorists away as there is evidence that the TSA does.

2) As tazi pointed out, your attempts of terrorism vs. successful terrorism ratio is just another example of how mathematically unsound your agency is. You'll need to examine L'Hospital's Rule if you want to even attempt to divide something approaching 0 by something else approaching 0. However, what the TSA really needs is a good course in Probability Theory, for its actions are a complete disgrace when one considers what the probability of a hijacking taking place with some items the idiocy of the TSA attempts to ban.

PS: Welcome to FlyerTalk!

------------------
"Give me Liberty or give me Death." - Patrick Henry


[This message has been edited by Spiff (edited 01-29-2003).]