P(typequestion)课件.ppt

Question Answering;Information Retrieval Tasks;Ad-Hoc Queries;Answering Ad-Hoc Queries ;Traditional IR;But not all queries are Ad-Hoc!;Documents are not Facts;Question Answering as Retrieval;Question Answering;QA as a Comprehension Task;QA as a stepping stone;QA Methods;Lecture Outline;Answer Type Identification;NASSLI!;Answer Type Identification;Wh-Words;Difficult to Enumerate All Possibilities Though;WordNet;WordNet For Answer Typing;Lecture Outline;Answer Typing gives the Preference…;Some are Simple…;… Others Complicated;Use WordNet for Type Identification;Simple Answer Extraction;Lecture Outline;Learning Answer Typing;What training data?;Trivia Questions!;MI Model;MaxEnt Model;Maybe you don’t even need training data!;Lecture Outline;Is Answer Typing Enough?;Answer Context;Using Context;Another alternative;Beyond…;Lecture Outline;Local Alignment;Local Alignment;Local Alignment;Local Alignment;Local Alignment;Local Alignment;Local Alignment;Local Alignment;Build a Statistical Model;;Surface text Patterns;Birthday Templates;Web Search to generate patterns;How can we pick good patterns?