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This paper generalizes, by the use of compound distributions, a result of HAIGHT (1966) on counts that are delayed but not lost. An application of Markov chains indicates a simple method of numerical evaluation of the distributions involved. Finally a continuous time analogue is studied. [ABSTRACT FROM AUTHOR]

The paper is concerned with randomized experiments with one treatment. Two randomization schemes are considered: randomized pairs and unrestricted randomization. If effective at all, the treatment is supposed to affect the conditional distribution of the "experimental" variable Y given another variable X, called "predictor". The distribution of X is not affected by the treatment. Using the general theory published elsewhere, the paper deduces the locally asymptotically optimal test of the hypothesis that the treatment has no effect. Apart from the usual difficulties connected with asymptotic tests (how large must N be?), the theory is easily applicable in many "live" cases even though the conditional distribution of Y given X may contain nuisance parameters and be of unusual form. [ABSTRACT FROM AUTHOR]

The author responds to the paper "The Loading Problem," by Eilon and Christofides. He focuses on suggesting a solution to the problem. The recommended solution involves a heuristic algorithm that allegedly requires fewer computations than the one proposed by Eilon and Christofides. It is suggested that the simpler algorithm offered by the author reaches mathematical optimization as often as the aforementioned algorithm. It is further proposed that the algorithm presented by Eilon and Christofides cannot be used to solve multi-dimensional programming problems. The author goes on to discuss a numerical analysis that can be used for the allocation of industrial resources. Related mathematical models are discussed in detail. A table comparing the results of the two algorithms is also presented.

This paper considers the maximization of certain equivalent reward generated by a Markov decision process with constant risk sensitivity. First, value iteration is used to optimize possibly time-varying processes of finite duration. Then a policy iteration procedure is developed to find the stationary policy with highest certain equivalent gain for the infinite duration case. A simple example demonstrates both procedures. [ABSTRACT FROM AUTHOR]

This paper describes the use of multiple ranking procedures to analyze data generated from computer simulation experiments with models of management systems. After outlining the rationale for the use of multiple ranking procedures with computer simulation experiments and defining some basic terminology, we examine several specific multiple ranking procedures. Careful attention is given to the assumptions underlying the different multiple ranking procedures and the extent to which these assumptions are satisfied by the data generated by simulation experiments. An example model is included to illustrate the applicability of multiple ranking procedures to simulation experiments in management science. [ABSTRACT FROM AUTHOR]

This paper presents in a form convenient for applications a number of bounds for distributions with monotone hazard rate. These bounds, together with their proofs and various generalizations have been obtained by Barlow and Marshall (1964). However, many of them can be characterized only through solutions of transcendental equations, and machine calculation has been necessary to make them accessible. Section 2 gives a listing of the results, and those without explicit forms are tabulated. Section 3 lists various related bounds which are of interest for purposes of comparison, and for use when the hypothesis of monotone hazard rate is not satisfied. Applications of the bounds are discussed in Section 4, together with some numerical examples. [ABSTRACT FROM AUTHOR]

This paper presents an algorithm for yielding an improved initial dual solution of the transportation problem when the network flow algorithm of Ford and Fulkerson is used. (1) The algorithm is described. (2) It is demonstrated by means of a numerical example. (3) Computational experience is reported. 400 medium-sized (30 X 80; 50 X 60; 50 X 80) test problems with three different kinds of distance matrices and two different kinds of shipment quantity vectors were evaluated. The average improvement over the usual method was about 30%. [ABSTRACT FROM AUTHOR]

This paper is an extension of previously published work by Bernard O. Koopman to the general case of any number of tasks and any effect function. A systematic method for the numerical calculation of the maximum effect and its corresponding optimum distribution is presented in a form which is also suitable for solution on an automatic digital computer. For the special case of additive returns which saturate, a special graphical or numerical method for any number of tasks is presented with an example worked out in detail A similar method for multiplicative effects is sketched. [ABSTRACT FROM AUTHOR]

This paper is concerned with evaluating the reliability of a redundant configuration, given that at any random time its surviving components are operating with failure distributions that are dependent upon the set of failed components. An expression (9) is derived for the reliability of this class of configurations and is then generalized to obtain an expression (23) for the reliability of a similar configuration whose component failure distributions are dependent also upon the time of the last such failure. These expressions are then applied to evaluating the reliability of a stand-by configuration with off-line failures, and the reliability of a parallel configuration for which at least a certain number of components must survive in order that the configuration operate satisfactorily. [ABSTRACT FROM AUTHOR]

The queuing models constructed here have the feature that a service facility tends to lose its customers if they often encounter lengthy delays. Structurally, the arrival processes are assumed to depend on past waiting times, hence on past arrival and service processes. The cases investigated include a a service facility with several competitors and a facility with very many competitors; these correspond roughly to oligopoly and to perfect competition in micro-economics. For the duopoly case, approximate analytical solutions are presented along with graphs for numerical solutions. A data sample is given that is moderately consistent with the duopoly model. [ABSTRACT FROM AUTHOR]

The article discusses the econometric literature suggesting an exact F-test on a specific class of hypothesis in the context of a structural equation. The authors' consideration on is based on the consistency of the test which is similar to the recent asymptotic test, and the unique characteristic which is the possibility of the test to obtain an exact analytical expression for the power. Mathematical equations using different formula including that of matrices, as well as several dependent variables are also presented in the paper.

We discuss, with examples, the use of numerical methods to describe and compare patterns of differentiation between populations of organisms at low taxonomic levels. The role of such methods as adjuncts to the orthodox methods of experimental taxonomy is illustrated by an account of differentiation in Solanum L. Section Solanum (Maurella). [ABSTRACT FROM AUTHOR]

This article compares the properties of floristic and physiognomic-structural data in the numerical analysis of complex rain-forest communities. The article discusses previous work on the use of physiognomic-structural characters for the classification of vegetation and environmental types. It analyzes the data by both agglomerative polythetic and divisive monothetic methods. It notes that an analysis of the relative efficiency of recovery of environmental information for descending hierarchical levels provided no support for the familiar suggestion that structural characters are less efficient at lower levels.

This article presents a study which investigated the relation between mean square and block size in the analysis of similar plant patterns. Models of basic patterns have been prepared and the analysis of these suggests that the starting point for sampling is of importance. If the series starts towards the centre of a clump there is a strong possibility that the indicated peak mean square will be one block size smaller than the actual. A new method of field sampling is suggested which involves taking a slightly larger series of samples, and performing a number of analyses.

A table of critical values of the Wilcoxon Signed Rank Statistic is presented for N = 4(1)100 pairs of observations at one-tail probability levels of .00005, .0005, .0025, .005(.005).025, .050(.025).150, and .20(.05).45. Probabilities were computed accurately to at least 6 digits, regardless of the location of the decimal point. Therefore, all critical values are correct as tabled. Normal approximation probabilities were found to be biased, too small at the .05 level but too large at the .005 and .0005 probability levels. Approximation errors were less than 10% for all N >35 for the .05, .025, and .005 one-tail probability levels; but this degree of accuracy was not achieved at the .0005 level for N = 100. [ABSTRACT FROM AUTHOR]

Where Youden's extreme rank sum test is used, an early decision is often possible by performing the trials in sequence with the following method. After each trial is completed, the greatest lower bound and least upper bound of both extreme rank sums are calculated for all remaining trials. If the critical regions cover either or both intervals of the statistics or the intervals lie completely outside the critical regions, the round-robin test is terminated with the acceptance of the proper hypothesis. [ABSTRACT FROM AUTHOR]

An interactive mathematical programming approach to multi-criterion optimization is developed, and then illustrated by an application to the aggregated operating problem of an academic department. [ABSTRACT FROM AUTHOR]

The usefulness of group theoretic methods in solving integer programming (IP) problems is extended by procedures for controlling the size of the groups. The main procedure given shows how an optimal linear programming basis can be altered to reduce the magnitude of its determinant thereby reducing the size of the group induced by the basis. An adaption of Benders' mixed IP algorithm is given which uses these methods. Some limited computational experience is given. [ABSTRACT FROM AUTHOR]

A systematic computation procedure is given for determining redistribution of stock among several user activities when set-up charges are involved. The procedure is divided into two phases, the first of which determines whether any redistributions should be made at all. Then the second phase determines the total amount to be shipped or received at each activity. [ABSTRACT FROM AUTHOR]

Results are developed for play-the-winner sampling for choosing the better of two binomial populations when the maximum number of tests is specified. It is shown that for a fixed number of tests the probability of correct selection with alternating assignment exceeds that for play- the-winner sampling. However, when the probability of correct selection is fixed, neither sampling method is uniformly better than the other as measured by the expected number of tests on the poorer population, or on the total expected number of tests. [ABSTRACT FROM AUTHOR]

The article discusses the significance of mathematics in biomedical and biological research. It states that the implications of the instrumentation, computers, and modeling, has become increasingly important for the biology major to include mathematics as an integral part of his undergraduate studies. It suggests to design a one-year mathematics sequence for the biology major. The course will involve integration of basic ideas on set theory, algebraic systems, and analytic geometry. The course aims to help students learn useful mathematical techniques, gain appreciation for the role of mathematics in biology, and let them acquire a feeling for the mathematical way of thinking.