The use of context for correcting garbled English text

The paper describes two different methods for using context to correct garbled English text. The first makes use of a dictionary of English words containing their probability of occurrence. The second uses letter digram frequencies to roughly approximate English word probabilities. Probabilities of various letter substitutions are obtained from a confusion matrix of the simulated character recognizer whose operation produced the garbling. This information is combined using a maximum likelihood scheme to obtain word recognition or, if only digram information is available, the recognition of word approximations.