Wiley.

An automatic method is described for the solution of a certain family of problems. To belong to this family a problem must be expressible in the language of graph theory as that of finding a path between two specified nodes of a specified graph. The method depends upon the evaluation of intermediate states of the problem according to the extent to which they have features in common with the goal state. We define evaluation functions each of which assigns to any state of the problem a value which is in some way related to its'distance' from the goal state. Equivalently we assign to nodes of the corresponding graph values which are related to the distance over the graph from the goal node.

An experimental system that uses LISP to make a conceptual dictionary is described. The dictionary associates with each English word the syntactic information, definitional material, and references to the contexts in which it has been used to define other words. Such relations as class inclusion, possession, and active or passive actions are used as definitional material. The resulting structure serves as a powerful vehicle for research on the logic of question answering. Examples of methods of inputting information and answering simple English questions are given.

J. Math. Anal. Applic., 10, 174–205.

This paper discusses the discrete-time Bayesian optimal control of stochastic dynamic systems where some vectors, which augment the system state vectors and the observed state vectors by additional variables, constitute multi-dimensional Markov chains. Optimal control of such Markovian control systems is considered under the assumption that only a part of the components of such vectors is observed by the control system. Certain conditional probability densities needed in deriving optimal control policies are derived, and computational procedures which determine optimal control sequences are given.

Library translation 1122, Royal Aircraft Establishment.

AIAA Journal, 3 (8), 1445-1450.

Republished as The Mathematical Foundations of Learning Machines, San Francisco: Morgan Kaufmann Publishers, 1990McGraw-Hill. Republished in 1990.

"Meaning" may be assigned to a string in a context-free language by defining "attributes" of the symbols in a derivation tree for that string. The attributes can be defined by functions associated with each production in the grammar. This paper examines the implications of this process when some of the attributes are "synthesized", i.e., defined solely in terms of attributes of thedescendants of the corresponding nonterminal symbol, while other attributes are "inherited", i.e., defined in terms of attributes of theancestors of the nonterminal symbol. An algorithm is given which detects when such semantic rules could possibly lead to circular definition of some attributes. An example is given of a simple programming language defined with both inherited and synthesized attributes, and the method of definition is compared to other techniques for formal specification of semantics which have appeared in the literature.

This report is part of the RAND Corporation Paper series. The paper was a product of the RAND Corporation from 1948 to 2003 that captured speeches, memorials, and derivative research, usually prepared on authors' own time and meant to be the scholarly or scientific contribution of individual authors to their professional fields. Papers were less formal than reports and did not require rigorous peer review. This document and trademark(s) contained herein are protected by law. This representation of RAND intellectual property is provided for noncommercial use only.