 the notion relev analysi problem defin mutual relev queri document-collect indic essenti involv problem conceptu related in order consid problem question concept-format discuss turn requir definit concept an extension interpret suggest concept associ class conceptu-similar document user' similar- judgment provid empir data formal definit concept conceptu related it gener difficulti rule possibl defin concept related method propos sinc method base human relev-judgment natur adopt collaps seriou practic theoret consequ an altern approach propos elabor form part ii articl 