Strategic Lazy Incremental Copy Graph Unification

The strategic lazy incremental copy graph unification method is a combination of two methods for unifying hmture structures. One, called the lazy incremental copy graph unification method, achieves structure sharing with constant order data access time which reduces the cequired memory. The other, cal led ti~e s t r a t eg ic incremental copy graph unification method, uses an early fai lure f inding s t ra tegy which f i rs t t r ies to unify :;ubstructures tending to fail in unification; this method is; based on stochastic data on tim likelihood of failure and ,'educes unnecessary computation. The combined method .makes each feature structure unification efficient and also reduces garbage collection and page swapping occurrences, thus increas ing the total efficiency of natural language processing systems mainly based on I.yped feature s t ructure unif icat ion such as na tu ra l language analysis and generation sysl~ems.