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As linear programming models grow bigger and bigger in size, much actual data that must be memorized is often put on magnetic tape or disk, and consequently there is an improportionately fast rise in the consumption of computer time. To cut down this expense, on ever increasing effort Is mode to design more efficient algorithms. This paper is meant to support the effort. If is attempted to find some characteristics of the way pivot column is found. The number of repetitions of a certain transfer of data from tape to core memory is considered. After some simplification, the problem is restated in a general way. The generating function of the probability distribution and the moment generating function of the number of repetitions is found. Asymptotic formulas are given for the moments using result from a paper of S. Narumi [1]. The results may be applied to write very efficient routines that search for an extreme value in a table. Formulas provide a means of calculating the computer timings in this case. [ABSTRACT FROM AUTHOR]

The use of decision tables as a tool in systems analysis and for program specification is now becoming accepted. Rules on redundancy, contradiction, and completeness for limited entry tables were published in 1963. These ore usually used for checking, preceded if necessary by a conversion from extended to limited entry form. Processors which automatically translate tables to more conventional program usually base their diagnostic facilities on these rules. In this paper it is suggested that these rules ore unsatisfactory and that the important aspect of checking is to eliminate ambiguity from tables. Ambiguity is defined and discussed, and a procedure for producing checked out decision tables is proposed. The theoretical basis of the algorithm used is established. The importance of well-designed diagnostic facilities in decision table processors is emphasized. [ABSTRACT FROM AUTHOR]

Comments on articles published in earlier issues of the journal "Communications of the ACM." Discussion on techniques used in automatic segmentation of cyclic program structures;Focus on diverse techniques to assure the integrity of a data base;Information on algorithms to be followed by primitives in order to maximize the amount of parallel activity in a data base.

A technique of random choice is illustrated by application to the problem of assigning students to a fixed schedule of courses. Using the technique it is possible to reduce or eliminate difficulties that result when a popular section is filled and closed before oil students requesting and requiring it have been scheduled. The effectiveness of automatic scheduling is retained without loss of the students' privilege of picking favorite instructors. [ABSTRACT FROM AUTHOR]

Items can be retrieved from binary trees grown with a form of the Algorithm Quicksort in an average time proportional to log n, where n is the number of items in the tree. The binary trees grown by this algorithm sometimes have some branches longer than others; therefore, it is possible to reduce the average retrieval time by restructuring the tree to make the branches as uniform in length as possible. An algorithm to do this is presented. The use of this algorithm is discussed, and it is compared with another which restructures the tree after each new item is added. [ABSTRACT FROM AUTHOR]

The application of Kuhn's Hungarian Method to the problem of matrix reduction as needed in Gotlieb's method for timetable generation is described. The method is suited to both hand and computer calculation. Devices to improve the efficiency of the basic algorithm are discussed. [ABSTRACT FROM AUTHOR]