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Massive New Surveillance Program Uncovered by Wall Street Journal

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Re: Massive New Surveillance Program Uncovered by Wall Street Journal

#171

Post by barking »

jlgreco wrote: post #163
barking wrote: post #159

Earlier quoted context omitted.

Given that terrorists are very rare then the P(A|B) using your terminology (where A = terrorist and B= bad record) will be very low. But for for a fixed P(A) and P(B) then the higher the value there is for P(B|A) the higher the value of P(A|B) will be. If you have an enornmous haystack to search it's more efficient to look first where you're most likely to find needles.

P(B|A) can be 100%, but if P(A) is astronomically small (and it is) and if P(B) very high (and it is), then P(A|B) will be so low that it becomes clear P(B|A) is absolutely worthless. As an extreme example demsonstrating the necessity of considering P(A|B), suppose we observe that 100% the 9/11 hijackers had black hair (P(black hair|terrorist) = 100%) . That observation is worthless because P(terrorist|black hair) is…

In your extreme example you can see that people in the B' group (those who don't have black hair) can be safely excluded as suspects. So even in this artificial example you can see that knowing P(B|A) is of value.

Re: Massive New Surveillance Program Uncovered by Wall Street Journal

#172

Post by jlgreco »

barking wrote: post #171
jlgreco wrote: post #163

Earlier quoted context omitted.

P(B|A) can be 100%, but if P(A) is astronomically small (and it is) and if P(B) very high (and it is), then P(A|B) will be so low that it becomes clear P(B|A) is absolutely worthless. As an extreme example demsonstrating the necessity of considering P(A|B), suppose we observe that 100% the 9/11 hijackers had black hair (P(black hair|terrorist) = 100%) . That observation is worthless because P(terrorist|black hair) is…

In your extreme example you can see that people in the B' group (those who don't have black hair) can be safely excluded as suspects. So even in this artificial example you can see that knowing P(B|A) is of value.

You seem to have missed the part where the extreme example is not real life. If you exclude people without black hair from suspicion, then the baddies will find someone without black hair. You cannot assume P(B|A) will not be modified by the policies you adopt. ...well, you can if you are the TSA and don't actually have to answer to anybody....

P(B|A) will never be 100% anyway though, so even if the terrorists were unable to adapt it would not matter. The point is that even in the absurd event that you found a P(B|A) that was 100%, it doesn't mean it is useful. Or do you actually think that screening for black hair in the example would be worthwhile?

Re: Massive New Surveillance Program Uncovered by Wall Street Journal

#173

Post by tsotha »

joshuahedlund wrote: post #150
dreamdu5t wrote: post #116

Why I'm worried about a surveillance state? Because the people in charge will have their records protected while everyone else gets the surveillance. Our president committed crimes his justice department jails people for (illegal drugs). Drug testing is a perfect example of the surveillance state. The people who don't get tested? The testers. The legislators. The people in charge. I know there are technical problems…

This is a good point, although as we saw most recently with Petraeus, sometimes an expansive surveillance state can't help but ensnare its own leaders, and this often accidentally leads to its limitations (as a bill requiring warrants for emails is now making its way through the Senate)

The Petraeus affair didn't come to light because of surveillance. That was a garden variety love triangle that blew up. The FBI wouldn't have known if they hadn't been told.

Re: Massive New Surveillance Program Uncovered by Wall Street Journal

#174

Post by tsotha »

alan_cx wrote: post #51
barking wrote: post #27

Earlier quoted context omitted.

None. By their nature, measures like this annoy people. If this was the 12th of September 2001 would your opinion be different and if so, why?

As a Brit, I have a huge problem with all this. In the old days of US funded IRA attacks against amongst other things, our government, we never let the terrorists win. We didn't budge our principles or give up core freedoms. Sure our side did some very iffy things to combat the terror, but it was still illegal. We didn't try to legitimise it by tearing up principles that applied to normal people. But once 9/11 happen…

>In the old days of US funded IRA attacks against amongst other things, our government, we never let the terrorists win.

Are you implying our government funded the IRA? Also, it's pretty rich being criticized by a Brit for the surveillance state. You guys have a camera system that would have made Orwell proud.

Re: Massive New Surveillance Program Uncovered by Wall Street Journal

#175

Post by tucosan »

jacquesm wrote: post #161
angersock wrote: post #157

Earlier quoted context omitted.

You seem to have been around (here at least) for a while... is there a story here, or are you just cutting off your nose to spite your face? EDIT: Removed leading "Honestly?". Am serious if an experience led to this.

I've lived on the US/Canadian border for several years and I've seen enough of US immigration to last me a lifetime. The specific incident that made me decide to stop visiting the US took place at an airport but that merely made the bucket overflow, it was already pretty full.

Now I am curious. Care to go into detail on either the specific case that made "your bucket overflow" or the overall situation that maddens you so much? I haven't been to the US for over a decade now and only pick up things on the news here and there...

Re: Massive New Surveillance Program Uncovered by Wall Street Journal

#177

Post by jacquesm »

tucosan wrote: post #175
jacquesm wrote: post #161

Earlier quoted context omitted.

I've lived on the US/Canadian border for several years and I've seen enough of US immigration to last me a lifetime. The specific incident that made me decide to stop visiting the US took place at an airport but that merely made the bucket overflow, it was already pretty full.

Now I am curious. Care to go into detail on either the specific case that made "your bucket overflow" or the overall situation that maddens you so much? I haven't been to the US for over a decade now and only pick up things on the news here and there...

> Now I am curious. Care to go into detail on either the specific case that made "your bucket overflow" or the overall situation that maddens you so much?

No.

> I haven't been to the US for over a decade now and only pick up things on the news here and there...

My last visit to the states was in 2005, so we're getting to that decade. I used to go at least once every year, sometimes more often. But until the madness is brought under control (probably not within my lifetime) it's not going to happen again. Too bad, really.

Re: Massive New Surveillance Program Uncovered by Wall Street Journal

#178

Post by sesqu »

adventured wrote: post #36

Give a government trillions to spend in an era of massive government programs and vast new storage & surveillance technology, and it should be obvious what you're going to get. The only possible way to stop it is to starve the beast of funds to spend. Cut the government in half, and let's see if they can still afford all the shiny new big brother toys.

"Starving the beast" reminds me of the rhetoric that's tied in with the fiscal cliff business. The left's answer to that has been that it appears the beast really likes toys, far more than it enjoys exercise or a healthy diet.

Re: Massive New Surveillance Program Uncovered by Wall Street Journal

#179

Post by whatshisface »

Strshps1MoreTim wrote: post #176
jacquesm wrote: post #169

Earlier quoted context omitted.

Please leave.

Why?

Simply stating what you believe is frowned upon here, you are supposed to include your reasons.

The basic assumption that we all hold about our opinions is that everyone else would believe in them too if they knew the facts we did, so it is best to accompany all statements of opinion with a logical argument for their validity.

Re: Massive New Surveillance Program Uncovered by Wall Street Journal

#180

Post by pyre »

tsotha wrote: post #173
joshuahedlund wrote: post #150

Earlier quoted context omitted.

This is a good point, although as we saw most recently with Petraeus, sometimes an expansive surveillance state can't help but ensnare its own leaders, and this often accidentally leads to its limitations (as a bill requiring warrants for emails is now making its way through the Senate)

The Petraeus affair didn't come to light because of surveillance. That was a garden variety love triangle that blew up. The FBI wouldn't have known if they hadn't been told.

Their investigation is what is being referred to here. Their ability to dig into the email accounts without any oversight.
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