Limits of Exact Algorithms For Inference ofMinimum Size Finite State

We address the problem of selecting the minimum sized nite state machine consistent with given input/output samples. The problem can be solved by computing the minimum nite state machine equivalent to a nite state machine without loops obtained from the training set. We compare the performance of four algorithms for this task: two algorithms for incompletely speciied nite state machine reduction, an algorithm based on a well known explicit search procedure and an algorithm based on a new implicit search procedure that is introduced in this paper.