High speed string edit methods using hierarchical files and hashing technique

Two dictionary-based methods for correction of strings with errors are proposed. The first method uses a hierarchical file based on two kinds of class name expression. The second method applies a hashing technique to methods already proposed. The correction rates of the two methods are the same. An experiment using 3782 words of length 6 characters shows that the computing time of the second method is 0.8% of that of the weighted Levenshtein distance method in the case of a substitution recovery