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Hardest captcha ever?

random.irb.hr

61–70 of 125 posts

Re: Hardest captcha ever?

#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).

Re: Hardest captcha ever?

#62
post #38

The hardest captcha I've come across is the audio one used by Google on https://www.google.com/accounts/NewAccount . Click the little wheelchair icon to hear it. It's so hard to decipher, it almost comes across as a cruel joke at the expense of blind people. These are much easier, in that I can actually understand them.

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…

A few years back I attended a tech talk from T.V.Raman (of emacspeak fame) and he was making fun of us, poor non-blind users, for being so slow at deciphering the bursts of sounds from the screen reader.

He, and other blind computer scientists that were present at the talk, was so used to the screen reader that could crank its speed up to impossible speeds for non-blind users (that don't exercise their hearing sense that much).

The same applied to the tiny distortions in pitch and tone that he'd use as a replacement for syntax coloring.

Pretty amazing.

Re: Hardest captcha ever?

#63
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.

Mine had a complex multiplication problem but had 0 as a multiplier. Can't get easier than that!

Re: Hardest captcha ever?

#66
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.

Yep, I saw a lot of derivatives of a constant, and multiplies by zero. There were a couple that weren't obviously 0, but I wouldn't be surprised if most of the actual answers were 0.

Re: Hardest captcha ever?

#67

The hardest captcha I've come across is the audio one used by Google on https://www.google.com/accounts/NewAccount . Click the little wheelchair icon to hear it. It's so hard to decipher, it almost comes across as a cruel joke at the expense of blind people. These are much easier, in that I can actually understand them.

This CAPTCHA is actually designed to ensure that the only entity that can decipher it is Satan himself.

Wow.

Re: Hardest captcha ever?

#68
post #45
post #11

I don't think it would be hard to do, in fact, they reverse the whole point of a CAPTCHA. A CAPTCHA is supposed to be a task that is easy for humans, but difficult for computers. High-level mathematics is difficult for humans but easy for computers. They do have some success of telling computers and humans apart, though.

High-level mathematics is difficult for humans and provably impossible for computers.

What kind of high-level mathematics is provably impossible for computers, but merely difficult for suitably-trained humans?

If you're thinking of either of Gödel's incompleteness theorems, you may be slightly mistaken about what they say. In general, a human operating by rigorous standards of proof is no more able to prove the completeness and consistency of certain formal systems—using the tools provided by those formal systems—than a machine can.

If, as a human, you somehow prove the consistency of these particular formal systems, you run smack into Gödel's second theorem: For any formal effectively generated theory T including basic arithmetical truths and also certain truths about formal provability, T includes a statement of its own consistency if and only if T is inconsistent. Thus, any proof of consistency is self-defeating, whether it's made by neurons or silicon.

Really, math doesn't care what parts of the periodic table you use to prove things. :-)

Re: Hardest captcha ever?

#69
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'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 long time, there's plenty of good material out there to learn it and people who understand it to teach it, there's no real reason it shouldn't be required curriculum these days.

Re: Hardest captcha ever?

#70
post #38

The hardest captcha I've come across is the audio one used by Google on https://www.google.com/accounts/NewAccount . Click the little wheelchair icon to hear it. It's so hard to decipher, it almost comes across as a cruel joke at the expense of blind people. These are much easier, in that I can actually understand them.

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…

(Was it Sam H.?)

When I was at MIT I had a lab partner who was blind for I think 6.002 or 6.003. I remember that one side-effect of using a screen reader was that he easily "recited" code, which I don't think most sighted programmers could do fluently.

Of course, in order to understand what he was reciting, my only hope was generally to try to type it into a text editor, format it and look at it. (And it's also hard to transcribe code being read to you.)

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