Please extract the Task and Method from the sentence.

Sentence : This paper introduces a  system for categorizing unknown words . The  system  is based on a  multi-component architecture  where each  component  is responsible for identifying one class of  unknown words . The focus of this paper is the  components  that identify  names  and  spelling errors . Each  component  uses a  decision tree architecture  to combine multiple types of  evidence  about the  unknown word . The  system  is evaluated using data from  live closed captions  - a genre replete with a wide variety of  unknown words .
Task : categorizing unknown words
Method : multi-component architecture, decision tree architecture

Sentence : This paper presents a new approach to  statistical sentence generation  in which alternative  phrases  are represented as packed sets of  trees , or  forests , and then ranked statistically to choose the best one. This representation offers advantages in compactness and in the ability to represent  syntactic information . It also facilitates more efficient  statistical ranking  than a previous approach to  statistical generation . An efficient  ranking algorithm  is described, together with experimental results showing significant improvements over simple enumeration or a  lattice-based approach .
Task : statistical sentence generation, statistical generation
Method : statistical ranking, ranking algorithm, enumeration, lattice-based approach

Sentence : In this paper, we describe the  pronominal anaphora resolution module  of  NAME_1  , a portable  English understanding system  . The design of this module was motivated by the observation that, although there exist many theories of  anaphora resolution  , no one of these theories is complete. Thus we have implemented a  blackboard-like architecture  in which individual  partial theories  can be encoded as separate modules that can interact to propose candidate  antecedents  and to evaluate each other's proposals. 
Task : 
Method :  Your entire response should be in English, and in all capital letters.
user