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A lot of AI is about vector space these days.

https://www.kaggle.com/c/word2vec-nlp-tutorial/forums/t/1234...

"That interim also saw dedicated attempts on the part of Google’s competitors to catch up. (As Le told me about his close collaboration with Tomas Mikolov, he kept repeating Mikolov’s name over and over, in an incantatory way that sounded poignant."

"Just as the chip-design process was nearly complete, Le and two colleagues finally demonstrated that neural networks might be configured to handle the structure of language. He drew upon an idea, called “word embeddings,” that had been around for more than 10 years. When you summarize images, you can divine a picture of what each stage of the summary looks like — an edge, a circle, etc. When you summarize language in a similar way, you essentially produce multidimensional maps of the distances, based on common usage, between one word and every single other word in the language. The machine is not “analyzing” the data the way that we might, with linguistic rules that identify some of them as nouns and others as verbs. Instead, it is shifting and twisting and warping the words around in the map. In two dimensions, you cannot make this map useful. You want, for example, “cat” to be in the rough vicinity of “dog,” but you also want “cat” to be near “tail” and near “supercilious” and near “meme,” because you want to try to capture all of the different relationships — both strong and weak — that the word “cat” has to other words. It can be related to all these other words simultaneously only if it is related to each of them in a different dimension. You can’t easily make a 160,000-dimensional map, but it turns out you can represent a language pretty well in a mere thousand or so dimensions — in other words, a universe in which each word is designated by a list of a thousand numbers. Le gave me a good-natured hard time for my continual requests for a mental picture of these maps. “Gideon,” he would say, with the blunt regular demurral of Bartleby, “I do not generally like trying to visualize thousand-dimensional vectors in three-dimensional space.”




but it turns out you can represent a language pretty well in a mere thousand or so dimensions

That makes sense, considering that Basic English has only a thousand words yet can express most concepts with enough words.


>> When you summarize language in a similar way, you essentially produce multidimensional maps of the distances, based on common usage, between one word and every single other word in the language.

The problem with word embeddings, or any distance-based model really, is that language doesn't work that way.

Chomsky has a standard example he uses to make this point: "Instinctively, Eagles that fly swim". He points out that in this phrase, the "instinctively" goes with "to swim" (as in "instinctively, they swim") even though the phrase, and the attachement, mean nothing (the phrase is nonsensical by design).

If the relation was really based on distance, we would expect "instinctively" to attach to "fly". The fact that it doesn't suggests that there is something else that makes us pick the correct association out of all the possible interpretations in that sentence.

Word vectors in their original form also have trouble with homonyms etc "faux amies": for instance, the word "cat"- is it referring to the animal, or to the Linux command? In vector space, there wouldn't be any difference, so the animal would be associated with the symbol ">" and the Linux command with "small" and "furry".


The "distance" referenced in your quote is not distance in a sentence, it's the distance between points in this abstract embedding space. Two completely different things. The Chomsky argument isn't really relevant here.


Meh. You're totally right, of course. What the hell was I thinking? :/


Language is something we intuitively understand. To get weak AI's potential, consider how many less-intuitive problems might be similarly addressable.


Word embeddings are actually quite neat. You get to the poinr where you can do QUEEN - OLD - PRESIDENT = GIRL. Or take the new google translate as a very practical example. But yes, it's not quite the groundbreaking progress that has been achieved in image and video.


>You get to the poinr where you can do QUEEN - OLD - PRESIDENT = GIRL.

That's very nice, but it seems to miss the difference between a monarchy and a presidential republic.




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