The terms in a query string can be divided into more-important (low-frequency) and less-important (high-frequency) terms. Documents that match only the less important terms are probably of very little interest. Really, we want documents that match as many of the more important terms as possible.query string에서 단어는, 더 중요하고(낮은 빈도의), 덜 중요한(높은 빈도) 단어로 나누어진다. 덜 중요한 단어만이 일치하는 document는 아마도 관심이 아주 적을 것이..