PHayes@SRI-KL (03/12/86)
English noun phrases aren't right-associative: natural languages are never that easy. Consider for example 'pressure cooker balance weight adjustment screw' (taken from T.Winograd ), which is a screw for adjusting the balance-weight of a pressure-cooker. Similar examples can easily be cooked up. Pat Hayes [If hyphens were included, the phrase would be right-associative: 'pressure-cooker balance-weight adjustment screw'. The hyphen is dropped for compound adjectives preceding a noun when the modifier is 1) a proper name, 2) a well-recognized foreign expression, or 3) a well-established compound noun serving as a compound adjective. (The hyphen can also be dropped if the compound is set apart by quotation marks or other means.) Case 3 means that terms such as high school are not hyphenated whereas high-level must be. Pressure cooker and balance weight would seem to fall under case 3. (I wish I were as certain of "image processing" and "pattern recognition" when used as adjectives.) The difficulty for machine translation and NL understanding is thus the recognition of compound nouns rather than the associativity per se. -- KIL]