An electronic aid for presenting equivalent information in concept identification

An electronic aid to assist in administering concept-identification problems with floating solutions is described. Digital circuitry generates all combination pairs from four selection switches, presents a particular comparison of these pairs, and, on command of the E, eliminates selected pairs from future comparisons. Each comparison is designed to minimize the information fed back to the S. The apparatus is used to administer and evaluate performance on conjunctive and disjunctive problems that are matched for information gain.