Idf was introduced as "time period specificity" by Karen Spärck Jones in a very 1972 paper. Even though it has worked well for a heuristic, its theoretical foundations are already troublesome for at least a few decades afterward, with lots of researchers attempting to come across info theoretic justifications for https://letters-of-credit29640.bloggerchest.com/38043765/the-single-best-strategy-to-use-for-predictive-analytics