Web Search Overview Crawling IR Big Issues in IR Relevance What is it? Simple (and simplistic)definition: relevant document contains the information that a person was looking for when they submitted a query to the search engine Many factors influence a person's decision about what is relevant: e.g., task, context, novelty, style Topical relevance (same topic)vs. user relevance (everything else) 13Web Search Overview & Crawling 13 Big Issues in IR ▪ Relevance ▪ What is it? ▪ Simple (and simplistic) definition: A relevant document contains the information that a person was looking for when they submitted a query to the search engine ▪ Many factors influence a person’s decision about what is relevant: e.g., task, context, novelty, style ▪ Topical relevance (same topic) vs. user relevance (everything else) IR