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Hardest captcha ever?

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Re: Hardest captcha ever?

#91

Post by CognitiveLens »

IsaacL wrote: post #78
crocowhile wrote: post #41

Earlier quoted context omitted.

Aristotle is very very disappointed with your logic, my friend. http://en.wikipedia.org/wiki/Inference#Examples_of_deductive...

I think you've misunderstood his post (or I've misunderstood yours (my friend))). He was saying that the linked website was illogical in using a method to distinguish humans from machines, that most humans would fail at. Grandparent wasn't attempting to construct his own logical argument.

But the logic of the CAPTCHA is "if you get this right, then you are human". Makmanalp was suggesting "if you get this wrong, you are not human", which does not follow logically from the CAPTCHA rule.

It is an example of "Denying the antecedent", or the inverse error: http://en.wikipedia.org/wiki/Denying_the_antecedent

Re: Hardest captcha ever?

#92

Post by kinofcain »

tassl wrote: post #90
brlewis wrote: post #38

Earlier quoted context omitted.

Once at MIT a blind student was showing me his screen reader. I couldn't make sense of the sounds at all, and asked if it was in some special code. He said no, it was normal language, just really fast. He had it read the current line on his terminal (this was late '80s). I could see the words it was supposedly reading, but I still couldn't map them to the brief burst of sound that came from the screen reader. So mayb…

This might be a little bit off-topic, but has somebody played with the tools that blind cs programmers use to program? Read/write/navigate,... What I mean is, has somebody any insight if it would be worth it, from a productivity point of view, to use those tools for non-blind people?

I used to do a lot of accessibility work, so I was somewhat proficient at JAWS and IBM's Home Page Reader.

JAWS, in particular, is quite powerful, but pretty daunting to learn. Compounding the clunkiness of JAWS is that many apps and sites aren't built with screen reader usability in mind – even if the developers made a good effort to ensure that it was possible to use their site in a screen reader, that all text was readable, etc, there's a huge difference between "possible" and "easy".

I thought it would be interesting, from an HCI perspective, to use a screen reader with something like a phone in your pocket, but sadly the learning curve is just too high, and there's not much motivation to improve it, either from the perspective of app/site developers (blind users are a rounding error) or even of the tool makers (blind users are highly motivated to learn their product, and will purchase it regardless of learning curve).

SEO, ironically, is the greatest thing to ever happen to blind users. All those people with tremendous financial incentive to make their sites spiderable to a text-only bot.

Re: Hardest captcha ever?

#93

Post by makmanalp »

CognitiveLens wrote: post #91
IsaacL wrote: post #78

Earlier quoted context omitted.

I think you've misunderstood his post (or I've misunderstood yours (my friend))). He was saying that the linked website was illogical in using a method to distinguish humans from machines, that most humans would fail at. Grandparent wasn't attempting to construct his own logical argument.

But the logic of the CAPTCHA is "if you get this right, then you are human". Makmanalp was suggesting "if you get this wrong, you are not human", which does not follow logically from the CAPTCHA rule. It is an example of "Denying the antecedent", or the inverse error: http://en.wikipedia.org/wiki/Denying_the_antecedent

Who is to say that "if you get this right, then you are human" is the valid premise? I'd argue that the correct one is "If you're human, you get CAPTCHAs right". :P

Re: Hardest captcha ever?

#94

Post by spc476 »

akie wrote: post #46
noamsml wrote: post #3

Most of these are really easy. I got a partial derivative of a constant. And honestly, if you can't answer basic math questions, you probably have no use for a quantum random bit generator.

and besides, I'm not entirely sure that these are "unbreakable" whatsoever. If you really want to break this, I'd do some math-specific OCR + WolframAlpha...

The image is in a clean looking font, so the OCR would probably be decent. Also, the question I got (Find the least real zero of the polynomial: p(x) = x^2 + 6x + 9) I typed, as is, into Wolfram Alpha and well, look at that, x = -3.

Re: Hardest captcha ever?

#97

Post by jmilloy »

Jach wrote: post #69
tallanvor wrote: post #48

Earlier quoted context omitted.

I'm not sure I'd consider calculus to be a basic math question, except in the context of uses where you have a real need for this level of randomness.

This is what [one of many things] is wrong with the educational system! Sure it's amazing that public schools have collectively taught people basic algebra (in theory), but we should set the new bar to Calculus and just keep pushing it up every so often. (I think Bayesian stats are more difficult than straight-up calculus though I'd like to see a public familiarity with both...) Calculus has been around for a pretty…

I would NEVER put calculus into required curriculum. Calculus is far less important than some simple number theory, logic, and the ability to think about abstract problems creatively. The tragedy is that we push towards calculus (which is really just advanced arithmetic until you get to, say college, real analysis) at the expense of these other skills.

Re: Hardest captcha ever?

#98

Post by elai »

tluyben2 wrote: post #61

Hmm. I see captcha's harder than that every day on numerous sites; with a lot of 'normal' captcha's you sit staring for minutes and then kind of gamble (like an OCR bot) to what it says. At least the formulas are clearly readable and there is a one correct answer to each of them, while this http://bit.ly/gKPgKH I cannot read (Google).

chithersom

Re: Hardest captcha ever?

#99

Post by repsilat »

philh wrote: post #75
noamsml wrote: post #3

Most of these are really easy. I got a partial derivative of a constant. And honestly, if you can't answer basic math questions, you probably have no use for a quantum random bit generator.

I got "find the least real zero of the polynomial: -7 * 4 - 7". Somehow I doubt "mu" would be accepted. (That sort of think has only shown up once over multiple refreshes though.)

Just to prove you are a human, please answer the following math challenge.

-6 + 5 * 0 = ?

(I guess I just got lucky?)

Re: Hardest captcha ever?

#100

Post by HelloBeautiful »

jmilloy wrote: post #97
Jach wrote: post #69

Earlier quoted context omitted.

This is what [one of many things] is wrong with the educational system! Sure it's amazing that public schools have collectively taught people basic algebra (in theory), but we should set the new bar to Calculus and just keep pushing it up every so often. (I think Bayesian stats are more difficult than straight-up calculus though I'd like to see a public familiarity with both...) Calculus has been around for a pretty…

I would NEVER put calculus into required curriculum. Calculus is far less important than some simple number theory, logic, and the ability to think about abstract problems creatively. The tragedy is that we push towards calculus (which is really just advanced arithmetic until you get to, say college, real analysis) at the expense of these other skills.

IMHO you don't understand Calculus good enough yourself. It's one of the most powerful tools humankind has come with. A couple of simple ideas aplicable practically everywhere.
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