31–39 of 39 posts
Earlier quoted context omitted.
Probably not. People are bad at random: http://scienceblogs.com/cognitivedaily/2007/02/05/is-17-the-...
I think his point is valid exactly because people are bad at randomness.
Oh, heh, I can see it that way now. I had intended my comment to say that, since you'd be trying to reach that set of ratios to hide things, you'd probably fail miserably against any competent analysis.
> Eventually we turned to the last items in the Oculist trove: nine copies of a four-page document written in a mixture of old German, Latin, and the Copiale’s coded script. The message was more or less identical in every set. I feel kind of sorry for them, that at the end of their journey they found what was essentially a Rosetta Stone for the code they were decoding.
I suspect there's a second code hidden in there. From the article, describing the code symbols that are Roman letters: These unaccented Roman letters appeared with the frequency you’d expect in a European language. But they don’t represent letters—they mark the spaces between words. It's implausible that these characters just happen to appear with a language-like frequency distribution and are all meaningless spaces.…
Unless they simply took random letters from some other text to get their spaces, in which case you'd get the correct frequency, in a sufficiently large text, with no meaning.
Question (maybe a dumb one) but how does an algorithm account for symbols that might mean a series of letters? Or a symbol that stands for a different letter depending on the symbol before or after it?
You can analyse texts you believe to be similar (in language, period, subject, etc) to the coded message you are attempting to crack, and use that to build tables of these n-grams in various semantic units.
Of course, these are useful in many more things than code-breaking, and Google have various datasets they make publically available.
The Google books ngram viewer[2] is a fun tool to play around with, or for the more serious, you can download a corpus of ~24GB of analysed web data they've crawled (from around 1 trillion source words)[3]
One actual example of a code constructed in the manner described is the Playfair cipher[4] which was used for a time in the late 1800s, but is now thoroughly broken.
[1] https://en.wikipedia.org/wiki/N-gram
[2] http://books.google.com/ngrams
[3] http://googleresearch.blogspot.co.uk/2006/08/all-our-n-gram-...
Earlier quoted context omitted.
It's implausible that these characters just happen to appear with a language-like frequency distribution and are all meaningless spaces Really? If I were to try to pick random letters I suspect I would end up mirroring the frequency that they appeared in English.
Probably not. People are bad at random: http://scienceblogs.com/cognitivedaily/2007/02/05/is-17-the-...
Testing the "random distribution" like it was done - with a small sample size - is ineffective at best
> Eventually we turned to the last items in the Oculist trove: nine copies of a four-page document written in a mixture of old German, Latin, and the Copiale’s coded script. The message was more or less identical in every set. I feel kind of sorry for them, that at the end of their journey they found what was essentially a Rosetta Stone for the code they were decoding.
That sentence says the nine copies (sets) were more or less identical not that the german latin and copiale were translations of each other.