--- Vladimir Nesov <[EMAIL PROTECTED]> wrote: > Adult can do tricks not accessible to a child, increasing efficiency > of language learning, and this process can make use of completely > different information. Explicit learning of difference between > categories is faster than unsupervised learning of such distinction. > Syntax can be regarded as such caricature of natural language that > helps in forming new categories relevant for it. Sometimes, categories > required for obtaining expertise in certain domain may never form > without supervised learning (it's hard to invent something, but easy > to learn). For example[*], Japanese speakers can't distinguish 'R' and > 'L' sounds, as in Japanese these are interchangeable and pronounced > closer to each other. The best way to teach the distinction is by > exaggerating both sounds, so that categories can be formed, which then > allows differentiation between normal sounds. > > > * JL Mcclelland, 2006. How Far Can You Go with Hebbian Learning, and > When Does it Lead you Astray?
Like English speakers learning Hindu cannot learn to speak the 3 different versions of the 'k' sound because they sound the same. Or the Spanish speaker who pronounces "sit" as "seat" because there is no equivalent vowel sound in Spanish and both words sound the same. The part of the brain responsible for auditory phoneme recognition becomes read-only by age 6. So we all speak foreign languages learned at later ages with an accent. People do not learn grammar by being given grammatical rules, because we still don't know what they are. Grammar rules seem to have a Zipf distribution, like vocabulary. About 200 words account for half of the tokens in text, and then it gets complicated. Likewise, a small number of rules cover a lot of the cases, like (S ::= NP VP, NP := det adj noun, etc). But after this point, you run into huge number (nobody know exactly how many) of idioms and special cases like "what/why/how in the world?" that makes language immensely complex. By the time you are old enough to learn the concept of grammar, you have already learned more of the rules than anyone has ever been able to write down. Understanding how children learn language helps one understand why rule-based language models like parsers have been a failure, and statistical methods have been a relative success (as measured by data compression, and applications to speech recognition and OCR). Language has evolved to be learnable by the human brain. If a construct isn't learnable, it disappears. Children learn by example and usage, not explicit rules. Each level is learnable from the earlier levels, namely phonemes shortly after birth, word segmentation at 7-10 months, semantics beginning at 12 months, and grammar at 2-3 years. -- Matt Mahoney, [EMAIL PROTECTED] ------------------------------------------- agi Archives: http://www.listbox.com/member/archive/303/=now RSS Feed: http://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: http://www.listbox.com/member/?member_id=8660244&id_secret=101455710-f059c4 Powered by Listbox: http://www.listbox.com
