2. The method of claim 1 , wherein said one or more programmed processor devices performs extracting said one or more first, second, third and fourth features in parallel.
1. A method for extracting features from a query comprising a text string, said method comprising: identifying a syntactic pattern rule associated with said query, said pattern rule identified from a set of pattern rules that define common lexical answer types (LATs), a first feature of said extracted features comprising an identified pattern rule; checking for prior instances of a detected lexical answer type (LAT) and computing a LAT word frequency based on said prior instances, a second feature of said extracted features comprising a computed frequency of a query word being a candidate LAT; obtaining a parse tree data structure associated with said query; identifying grammatical relations amongst words associated with said candidate LAT in said parse tree structure, a third feature of said extracted features comprising a part of speech of the candidate LAT, determining whether the candidate LAT word co-references some other word in said query recognized as a LAT, a fourth feature of said extracted features comprising a co-reference information, and applying a model to said extracted first, second, third and fourth features to produce a confidence value representing an estimated accuracy of a detected query LAT, wherein one or more programmed processor devices performs said identifying a syntactic pattern rule, checking for prior instances, obtaining the parse tree data structure, identifying grammatical relations, and determining LAT word co-references, and model applying.