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Precise model 

metanymous в посте Metapractice (оригинал в ЖЖ)

Precise model
https://docs.google.com/spreadsheet/ccc?key=0Agi80kQiMwG8ckswaVhSQjhGVkJVLW81bFllYW9CdkE&pli=1#gid=0