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Merton points out that "the most precise significance of the word function is of course found in mathematics …. " But, says Martindale, "The work of most of the recent functionalists has been at the opposite pole from this meaning." Consequently, assertions made by functionalists have not always been received with the degree of confidence that their authors might consider appropriate. It is the purpose of this paper to suggest a way in which qualitatively formulated propositions of a functional kind may be translated into a language which points to empirical referents and thus, if all goes well, leads in the end to the formulation of mathematical equations. [ABSTRACT FROM AUTHOR]

Rate is one of the most broadly useful concepts in mathematics, expressing the relationship between two variables in terms of an artificial unit. Rate can be defined as the average number of units of one variable per unit of another. Rate of speaking is not essentially different from other applications of the concept. The greater difficulties it presents are due in part to the difficulty of selecting an appropriate unit for analysis and in part to the complexity of the variables of which it is composed, since many of these variables are analyzable into other units with complex interrelationships. The present paper concentrates on the relations among rate variables and their consequences for research design and interpretation. Many studies have measured rate in words or syllables per minute. The procedure involves a count of the number of words or syllables in a given utterance, divided by the length of time consumed.

This paper considers some problems in the probabilistic analysis of physical evidence in criminal investigations. Two basic assumptions are made: (1) That the number of persons or objects possessing a particular set of properties can be considered as a random variable, and (2) that it is possible to estimate the probability function of this random variable. Two models (one with and one without the assumption that the suspect is a random selection from the set of possible suspects) which arc applicable to the evaluation of partial transfer evidence--an important category of physical evidence that is found in most criminal investigations--are developed. A detailed analysis of the models and an example are presented for the case when the estimated probability distribution is binomial with an expected value less than 1. As the expected value becomes smaller, the assumption of randomness in the selection of the suspect becomes immaterial to the evaluation of the evidential significance. [ABSTRACT FROM AUTHOR]

A common problem in many areas is to achieve a combination of control variables which will simultaneously maximize all of the responses which are functions of the control variables. The fact that in general we can not simultaneously maximize all of the responses has led to the formulation of compromise solutions to this vector maximum problem. A point in the control variable space is better than a second point if each response at the first point is greater than or equal to the corresponding response at the second point. If a point is such that there is no better point, it is said to be admissible, or efficient. A set of points is complete if given any point not in the set there is a point in the set which is better. In this paper this formulation is used to consider the allocation of sample size to several strata when there are several characteristics of interest. [ABSTRACT FROM AUTHOR]

The article presents suggestions for more accurate measurement of some figure drawing variables. Suggestions are offered to increase the precision and reliability of scoring certain traditional drawing variables. If drawings done along different axes are to be compared for location, they may be more accurately scored using a procedure. Vertical imbalance may easily be scored with an inexpensive protractor. The score might be the angle the center of the figure makes with the bottom edge of the paper. The angle can be read from the protractor in degrees.

In this paper confidence bands are given for simple linear model. The confidence bands that are given are straight lines rather than curves and are either (1) parallel or (2) trapezoidal. The confidence bands are over a finite length interval. [ABSTRACT FROM AUTHOR]

In this paper we review the literature on the problem of handling multivariate data with observations missing on some or all of the variables under study. We examine the ways that statisticians have devised to estimate means, variances, correlations and linear regression functions from such data and refer to specific computer programs for carrying out the estimation. We show how the estimation problems can be simplified if the missing data follows certain patterns. Finally, we outline the statistical properties of the various estimators. [ABSTRACT FROM AUTHOR]

This paper describes certain quota sampling procedures and attempts to show that they are very close to traditional probability sampling. Quotas are shown to depend on availability for interviewing and evidence is presented to show that sex, age, and employment status are reasonable predictors of availability. Quota sampling methods are not unbiased but data are presented which suggest that the bias is generally of the order of 3 to 5 per cent. It is shown, however, that the cost differentials between these quota samples and call-back samples are small. The major advantage of this new procedure may well be the speed with which interviewing may be completed during crises such as the Kennedy assassination. [ABSTRACT FROM AUTHOR]

The Bradley-Terry model for a paired-comparison experiment with t treatments postulates a set of t 'true' treatment ratings π1, π2, ..., π1 such that π1 is ≥ 0, σpi;i = 1 and the probability for preferring treatment i to treatment j is π2 (π2 + πj)-1. Thus, according to this model, every comparison of two treatments results in a definite preference for one of the two. This is an unrealistic restriction since when there is no difference between the responses due to two treatments, any method of expressing preference for one over the other is somewhat arbitrary. This paper considers a modification of the Bradley-Terry model by introducing an additional parameter, called threshold parameter, into the model. This permits 'ties' in the model. The problem of estimation and tests of hypotheses for the parameters of the modified model is also dealt with in the paper. [ABSTRACT FROM AUTHOR]

This paper deals with methods of "cluster analysis". In particular we attack the problem of exploring the structure of multivariate data in search of "clusters". The approach taken is to use a computer procedure to obtain the "best" partition of n objects into g groups. A number of mathematical criteria for "best" are discussed and related to statistical theory. A procedure for optimizing the criteria is outlined. Some of the criteria are compared with respect to their behavior on actual data. Results of data analysis are presented and discussed. [ABSTRACT FROM AUTHOR]

The article describes a process for determining migration probability. A stochastic process may be defined as a process which develops over time and where events at time 2 are not independent of events at time 1. This lack of independence may be viewed in probabilistic terms. Since the application of stochastic probability processes to problems of predicting individual behavior requires data obtained from case studies where each individual can be classified with respect to a given set of categories at successive points in time, the projected analysis required a set of individual longitudinal migration histories. Consequences of the basic mechanism of the model utilized in the paper are also detailed.

Economic statisticians do not enjoy an untarnished reputation for accurate forecasting. We have managed, over the years, to come up with some memorable failures. While we have also had our share of successes, they are not as well remembered nor as numerous as we should like. Recently, however, we have begun to pay more attention to the record, and a substantial body of evidence on forecasting performance has accumulated. In this paper I propose to review this record, try to arrive at a balanced appraisal, and offer some suggestions for improvement. [ABSTRACT FROM AUTHOR]

In many scientific investigations, it is desired to bring together, or link, two or more documents which represent the same individual, even though these documents do not contain a unique identifier and were derived from different sources. In medical and public health research and elsewhere, this problem is known as the document linkage problem. This paper considers some aspects of classifying pairs of documents into one of two populations when their items are identifying information, where each item of information can take on three distinct values correct, incorrect or missing. Section I identifies three document linkage problems. Sections 2 and 3 deal with the mathematical formulation of the multivariate document linkage problem. Section 4 gives the classification procedure and Section 5 deals with the application of the theory to a problem in the field of public health. [ABSTRACT FROM AUTHOR]

This paper discusses the application of Bayes's theorem to those cases where the true state of the world is not known with certainty. An algorithm is proposed that relaxes the requirement of Bayes's theorem that the true data state be known with certainty by postulating a true but unobservable elementary event, ω, which gives rise to posterior probabilities which reflect the uncertainty of the data. A derivation is presented for the calculation of Bayesian posterior probabilities which uses as its input these probabilities, rather than the true event, o, which is assumed to be unavailable. Suggestions are made as to the application of this modification of Bayes's theorem to cascaded inference processes. [ABSTRACT FROM AUTHOR]

In this paper we show a new method to determine the sphericity of sand particles with sedimentary analysis. We use two different sieves: the one with open squares: the side is a and the diagonal d = a√2; the other with circular openings: the diameter is D. Experimentation shows that elements crossed the open-square sieves in diagonal positions. When we reported the cumulative curves into arithmetic or semi-logarithmic graphs, we used the value d and not the side square a. A sediment C, which is composed of not very angular or subspherical particles, is represented by two cumulative curves on the same graph. If a sediment A is very angular, the two curves are disconcerted. The sediment B is subspherical, the difference between the two curves is maximum, We call this difference δ which is equal to d-D. For C this difference is Δ, which is always inferior to δ. The absolute sphericity index Sa is the ratio Δ/δ in %. When the particles are very angular, sphericity values are 0—like A and when they are sphericals the index is 1 — like B. This index is determined with graphic solutions. The values obtained are comparable with those of visual charts. [ABSTRACT FROM AUTHOR]

In this paper the first two moments of the Statistic (treatment sum of squares)/(treatment +error sums of squares) over all possible random assignments of treatments to the experimental plots are obtained for two associate PBIB designs. They are compared with the corresponding moments of a central beta distribution to study the extent to which the normal theory test may serve as an approximation to the randomization test. It is found that the approximation is reasonable for some classes of PBIB designs. [ABSTRACT FROM AUTHOR]

The purpose of this paper is the presentation of formulae for obtaining matrix derivatives of the second order to use in making tests for maxima and minima. The theory of such second order derivatives is presented. These formulae require the rearrangment of the parameter elements in vector form and the transformed results feature Kronecker products, which have certain desirable properties. Application is made to several types of problems. [ABSTRACT FROM AUTHOR]

A multiple-choice item is called ideal if all its alternatives are equally attractive to every person who cannot answer the item correctly without guessing. This paper discusses reasons for attempting to construct ideal items, develops methods for testing whether items are ideal or at least more nearly ideal than other items, and presents examples of both ideal and nonideal items. [ABSTRACT FROM AUTHOR]

Before we can construct models for multilane traffic flow, we must be able to describe single-lane traffic. This paper considers some of these methods of description including the use of headway and counting distributions. Another method of describing point processes is by means of product densities. These are essentially joint probabilities of two or more vehicles passing a point at different specified times. Product densities have been used in many fields including particle physics, ecology, and road traffic. The idea of using product densities is simple and attractive, but they do have two major disadvantages: (i) except in simple cases, headway distributions are very difficult to derive from product densities, and (ii) product density estimates for different time lags are cor- related, so that tests of hypotheses are not easy to perform. An alternative to product densities is proposed. For want of a better name these are called termination rates. The termination rate after lag τ is the probability of a vehicle passing a point in a small interval of time, divided by the length of the small interval and conditional upon the last vehicle having passed a time τ previously. These are very similar to mortality rates for humans or scrap page rates for commodities with limited life-times. The interrelations between these statistics are quoted but not derived. Various sets of data are used to illustrate the less common statistics. Some analysis is given of a sample of data from the Congress (now Eisenhower) Expressway in Chicago. Variance to mean ratios are used to show that there is a strong correlation between lanes even though the autocorrelations of headways within lanes are very small. Bivariate termination rates have been estimated for each lane. Given a vehicle in one lane, it was found that the expected number of vehicles in a neighboring lane within 2 or 3 sec was enhanced by about 10-15 percent. [ABSTRACT FROM AUTHOR]

The traffic assignment and distribution problems are customarily treated as though they were independant rather than related and interacting. In this paper a combined traffic distribution-assignment model is formulated as a mathematical program, based on the equilibrium traffic distribution model and a linear programming assignment model. The behavior of this model using the DANZIG- WOLFE decomposition principle is investigated and illustrated by means of an example. A number of areas for extension are indicated and an alternative formulation that has certain advantages is also [ABSTRACT FROM AUTHOR]

This paper deals with a car-following model relating driver reaction time, temporal headway and deceleration response to accident frequency. The central goal is to assess the sensitivity of collision probability to a shift in expected reaction time. This problem reduces to determining the sensitivity of the probability of ruin to changes in the drift of the process of cumulative differences between reaction times and temporal headways. A diffusion-type approximation is used and it is shown that additive changes in mean reaction time correspond to multiplicative changes in collision probability. A numerical example is given to illustrate the potential effects of a mere 0.1 sec decrease in mean reaction time. [ABSTRACT FROM AUTHOR]

In many cases Bayes' theorem is an appropriate algorithm for the aggregation of probabilistic evidence. As with other statistical procedures, there are restrictions that must be taken into account. In the present paper we shall comment on several approaches that have been devoted to one of these restrictions; the incorporation of uncertainty about the true state of a datum. A datum is a variable which can be partitioned into equivalence classes. These classes represent the possible data states which will be also called events. In Bayes' theorem an event is an item of information which will be used for revising the opinion about the relative likelihood of hypotheses. In any specific situation only one of the possible events will be the true event. An event may come from a source whose reporting or observational accuracy is not perfect. An example may illustrate the issue. A medical doctor wants to come to a diagnosis. To achieve this he considers several data. One datum might be the result of a medical test, which has three possible states: positive, negative, inconclusive. If the doctor reports the state of the datum to be positive, he may be wrong by whatever reasons. That is, the report of an event must not necessarily coincide with the actual or true event of the datum under consideration. This kind of uncertainty about the true event in any specific situation is a characteristic of the source. In most cases it will reduce the diagnostic impact of an event. Whenever the report of an event and the true event coincide imperfectly, measures of source inaccuracy must be incorporated into Bayes' theorem. The task can be considered as two stage probabilistic induction. The first step is induction from the reported to the actual event, the second is induction from the actual event to the creditation of hypotheses. This is the reason why Gettys and Willke (1969) speak about "cascaded inference." [ABSTRACT FROM AUTHOR]

Statistical researcher M. Stone continues in his diligent search for flaws in the Bayesian theory of statistical inference. In the present paper he considers two examples in which Bayesian strong inconsistency can occur with a flat prior. Only a relatively few statisticians believe that a single theory of inference can be the answer for all of statistics. The committed Bayesian's, however, are prominent among such believers. There are, of course, substantial arguments against the Bayesian theory as a single theory of inference, a summary of these arguments may be may be found in D.A.S. Fraser. These arguments are not primarily concerned with the Bayesian method as a tool in the statistician's tool bag rather, they are concerned with the catholic claim for Bayesian theory and with the meaning and consequences of the theory in scientific contexts. The two examples considered by Stone are some what remote from Bayesian theory in a scientific context indeed, the theory will not rise or fall on the basis of the examples. Nevertheless the examples are extremely interesting they are concerned with implications of the theory, and they are presented with the attractive flair that we expect from Stone.

This article contains a bibliography of papers on multiple comparisons between 1966 and 1976. A. discussion of some of the more important developments during this period precedes the bibliography. [ABSTRACT FROM AUTHOR]

The author of this article has written to correct a problem he discovered in one of Bruce Weide's "recurrences" as printed in "A Survey of Analysis Techniques for Discrete Algorithms," in the December 1977 issue of the journal "ACM Computing Surveys." The author has commented that Weide's paper seems to contain an error in the solution of a recursion.

Recent advances in network equilibrium modeling provide efficient algorithms for solving the urban trip assignment problem. These models can be extended to incorporate the trip distribution problem with two types of variable demand functions. By reinterpreting the zone-to-zone trip variable, these models can be viewed as urban location models. This paper synthesizes these results and shows how several urban location models can be derived from the mathematical framework based on the network equilibrium problem. [ABSTRACT FROM AUTHOR]

This article presents information about December 1, 1980 issue of the periodical "ACM Computing Surveys." The five papers in this issue are primarily mathematical in nature. They provide theoretical treatments of the description, of programming languages, of efficient techniques for implementing and carrying out various algorithms, and of the representation of rigid solid objects. By probabilistic languages software developer C.S. Wetherell means the attachment of probabilistic information into the context free grammar describing a programming language. This is done in order to have a mathematical formulation of the statistical information available from that language. The intention of Wetherell's paper is, first, to describe the notion of probabilisitic context free grammars and, second, to discuss some of their applications in order to emphasize their value in programming language studies. Following a brief overview of context free languages, the author examines methods for adding probabilities to the grammar of a language in order to attach probabilities to strings of that language.

Computer-based systems for modeling the geometry of rigid solid objects are becoming increasingly important in mechanical and civil engineering, architecture, computer graphics, computer vision, and other fields that deal with spatial phenomena. At the heart of such systems are symbol structures (representations) designating "abstract solids" (subsets of Eucidean space) that model physical solids. Representations are the sources of data for procedures which compute useful properties of objects. The variety and uses of systems embodying representations of solids are growing rapidly, but so are the difficulties in assessing current designs, specifying the characteristics that future systems should exhibit, and designing systems to meet such specifications. This paper resolves many of these difficulties by providing a coherent view, based on sound theoretical principles, of what is presently known about the representation of solids. The paper is divided into three parts. The first introduces a simple mathematical framework for characterizing certain important aspects of representations, for example, their semantic (geometric) integrity. The second part uses the framework to describe and compare all of the major known schemes for representing solids. The third part briefly surveys extant geometric modeling systems and then applies the concepts developed in the paper to the high-level design of a multiple-representation geometric modeling system which exhibits a level of reliability and versatility superior to that of systems currently used in industrial computer-aided design and manufacturing. [ABSTRACT FROM AUTHOR]

The coming of mathematicians to the United States fleeing the spread of Nazism presented a serious problem to the American mathematical community. The persistence of the Depression had endangered the promising growth of mathematics in the United States. Leading mathematicians were concerned about the career prospects of their students. They (and others) feared that placing large numbers of refugees would exacerbate already present nationalistic and anti Semitic sentiments. The paper surveys a sequence of events in which the leading mathematicians reacted to the foreign-born and to the spread of Nazism, culminating in the decisions by the American Mathematical Society to found the journal Mathematical reviews and to form a War Preparedness Committee in September 1939. The most obvious consequence of the migration was an enlarged role for applied mathematics. [ABSTRACT FROM AUTHOR]

Applying a method of vectorized summation of refractive corrections, this paper sets out to examine the behaviour of the associated associated parameters, the sphere, the cylinder power and the axis of astigmatism. It introduces novel methods of determining their age-dependence and establishes their mathematical relationships. [ABSTRACT FROM AUTHOR]

The problem considered is the estimation of the population total of some characteristic from a simple random sample containing a few large or extreme observations. The effect of these large units in the sample is to distort the estimate of the population total. It is therefore important to correct the weights for such units or deflate their values at the estimation stage once they have been sampled and identified as unusually large units. In this paper, three estimators that alter the usual sampling weights have been considered. The efficiencies of these estimators have been worked out in terms of the ratio of the mean squared error of the usual estimator of the population total to the mean squared error of these estimators. A numerical study of these estimators is also discussed. [ABSTRACT FROM AUTHOR]