#7
Ese discurso de "porque ellos lo valen" (o nosotros) se cae cuando todo el aparato estatal va contra ti con abuso de poder, saltándose la constitución y los derechos humanos más básicos para enchironarte por algo erróneo o porque has pasado a ser "terrorista" o "antisistema" en sus papeles o datos que describen la realidad.
Quien apoye a sistemas de vigilancia se pierde lo más básico de bioestadística. Es como si alguien apoyara una causa donde una suma estuviera mal hecha:
http://www.badscience.net/2009/02/datamining-would-be-lovely-if-it-worked/
"[...] If you have 10 people, and you know that 1 is a suspect, and you assess them all with this test, then you will correctly get your one true positive and – on average – 1 false positive. If you have 100 people, and you know that 1 is a suspect, you will get your one true positive and, on average, 10 false positives. If you’re looking for one suspect among 1000 people, you will get your suspect, and 100 false positives. Once your false positives begin to dwarf your true positives, a positive result from the test becomes pretty unhelpful.
Remember this is a screening tool, for assessing dodgy behaviour, spotting dodgy patterns, in a general population. We are invited to accept that everybody’s data will be surveyed and processed, because MI5 have clever algorithms to identify people who were never previously suspected. There are 60 million people in the UK, with, let’s say, 10,000 true suspects. Using your unrealistically accurate imaginary screening test, you get 6 million false positives. At the same time, of your 10,000 true suspects, you miss 2,000.
If you raise the bar on any test, to increase what statisticians call the “specificity”, and thus make it less prone to false positives, then you also make it much less sensitive, so you start missing even more of your true suspects (remember you’re already missing 2 in 10 of them).
Or do you just want an even more stupidly accurate imaginary test, without sacrificing true positives? It won’t get you far. Let’s say you incorrectly identify an innocent person as a suspect 1 time in 100: you get 600,000 false positives. 1 time in 1000? Come on. Even with these infeasibly accurate imaginary tests, when you screen a general population as proposed, it is hard to imagine a point where the false positives are usefully low, and the true positives are not missed. And our imaginary test really was ridiculously good: it’s a very difficult job to identify suspects, just from slightly abnormal patterns in the normal things that everybody does.
Things get worse. These suspects are undercover operatives, they’re trying to hide from you, they know you’re data-mining, so they will go out of their way to produce trails which can confuse you.
And lastly, there is the problem of validating your algorithms, and callibrating your detection systems. To do that, you need training data: 10,000 people where you know for definite if they are suspects or not, to compare your test results against. It’s hard to picture how that can be done.
I’m not saying you shouldn’t spy on everyday people: obviously I have a view, but I’m happy to leave the morality and politics to those less nerdy than me. I’m just giving you the maths on specificity, sensitivity, and false positives."
Snowden ya dijo que la vigilancia no sirve y hace más daño a las personas inocentes. Es un chivato de la NSA perseguido por EEUU para meterle cadena pepetua sin hacer el juicio en abierto porque los secretos de estado tratados se quedan como tal (por eso él está en Rusia). Y seguramente sin posibilidad de revisión ni de hacer comisiones independientes. O sea, desde el secreto más absoluto.
Hay más pruebas, pero sólo hace falta ver a quién perjudican las filtraciones de Assange y otros, a quién jode de verdad el data-mining y a quién beneficia el war on terror.
Después hace falta un cerebro operativo y funcional. Aquí las cosas ya cojean.
