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This paper expands the diffusion of information models developed by Funkhouser and McCombs (1972) to include situations involving simple interaction processes and more complicated situations involving both mass mediated messages and interactively mediated messages. This paper develops discrete time models of information diffusion as opposed to the continuous time models developed by Coleman (1964) and Bartholomew (1967) and others. [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]

This paper presents the graphical analysis and design considerations of multi-input sine comparators whose mathematical analysis has already been presented in an earlier paper by the authors (Anti Kumar and Parthasarathy 1967). Particular emphasis is placed on the design of a circuit, using semiconductor components, which provides a quadrilateral polar characteristic on the impedance plane. Novelties of design include a reactance reach, increased tolerance to fault resistance as the fault point moves towards the relay location, directional feature and independent control of each line segment constituting the quadrilateral, so that the fault area and tho relay characteristic could be closely matched. Test results show the negligible transient overreach and a constant operating time which is 1 1/2 cycles or less, and irrespective of fault location. The flexibility of design enables it to be used as a three-zone stepped time-distance relay or in conjunction with pilot schemes.
Test results show the versatility of the unit and the flexibility of the comparator theory. By suitable modifications of only the input signals, any desired characteristics can be easily obtained as dictated by system requirements. Special care has been taken to use similar switching blocks so that replacement is rendered simple. [ABSTRACT FROM AUTHOR]

The paper deals with the problem of how people handle random events. Many accounts of the chance element in games and many attempts at general explanations of gambling assume that the actor accepts the events as unpredictable and passively awaits the outcome. A study of people playing roulette in a gaming club suggests that this is far from the case. Playing roulette can be seen as an exercise in 'skill' which depends upon the construction and maintenance of predictive theories. One form of theorizing attributes causal efficacy to the croupier and the game becomes a contest between croupier and player. This is reinforced by the croupiers as they attempt to manipulate their working conditions and status. Players may then adopt a non-arithmetic calculus of win and loss which confirms their theorizing. Losses are the 'entrance fee' to a public entertainment, whilst wins are evidence of a successful working strategy. [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]

The designing of some multi-factor "analytical" studies of survey data is considered in this paper. It is assumed that, for each factor, there are two categories of interest and these are to be compared. The main objective is to allocate the sample so that the desired precision for the specified contrasts is obtained at minimum cost. It is assumed that one may sample independently in each of the sub-populations under investigation. A model is employed to facilitate designing and analyzing such a survey. We discuss the relevance of this model for "analytical studies," and a few examples are presented. Several survey objectives are explored, and an optimal allocation is obtained for each. Two, three and four-factor studies are considered explicitly. [ABSTRACT FROM AUTHOR]

The paper reports the results of several sampling experiments investigating the sensitivity of various simultaneous-equations estimators to errors in the exogenous variables, stochastic coefficients, heteroskedastic disturbances and autocorrelated disturbances. The estimates studied are direct least squares, two-stage least squares, Nagar's unbiased k-class estimator, limited-information maximum likelihood, three-stage least squares, and full-information maximum likelihood. Stochastic coefficients altered the ranking of the estimators and increased their dispersions greatly. The other conditions did not produce great changes in the rankings of the estimators, the central tendencies of their distributions or the usefulness of their standard errors. [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 compares the Pearson Chi-Square and Kolmogorov goodness-of-fit tests with respect to validity under the following conditions: (1) the N independent observations are tabulated and arranged into k mutually exclusive groups that are equally probable under the hypothesis to be tested; and (2) both N and k are "small"; i.e., not greater than 50. A random sampling experiment was performed, and the results show that in general for the conditions considered, the Pearson test is more valid than the Kolmogorov test. [ABSTRACT FROM AUTHOR]

Dealt with in this paper is the analysis of phenomena involving simultaneous responses among members of small groups during a finite number of discrete time intervals. An exact combinatorial test obtained by conditioning on the sufficient statistics under a null hypothesis is proposed. A specific application of this test is given for the analysis of asthma attack data of asthmatic individuals. [ABSTRACT FROM AUTHOR]

The use of Fourier or spectral methods for the seasonal adjustment of economic and other time series has recently been suggested; see for example Hannah [3], [4]. The case in which the seasonal pattern does not change appreciably from year to year has been covered in some detail but methods appropriate to an evolving seasonal pattern have been given only a little attention. The present paper discusses the nature of evolving seasonal patterns which may arise in economic series and examines a method due to Harman which may be used when the pattern is changing slowly over time. Although the suggested method is not readily mechanized for routine application on a large scale since some personal judgments are called for, it is found useful in detailed studies and might well be applied to any series for which traditional methods are not adequate; it is also applicable to the problem of prediction. [ABSTRACT FROM AUTHOR]

In this paper harmonic analysis is employed to investigate regional variations of the annual march of precipitation over Canada. In order to examine the regional variations of the annual march of precipitation, the researcher is confronted with the problem of presenting variations of space as well as time. A method of objectively describing and mapping these space-time characteristics of precipitation is that of harmonic analysis. Before proceeding to examine the area distribution of the two major variance components, the annual and semiannual, it is useful to establish the distribution of the total variance and also the relationship of the two major components to the total variance and to one another.

Mathematical analysis of the radiation from a dielectric coated prolate spheroidal core loop antenna surrounded by a plasma sheath is considered in this paper. In order to satisfy boundary conditions, the angular prolate spheroidal function S(C,) of one region is expanded in terms of another region. Therefore, the formal results are presented in terms of infinite matrices. A choice of the truncation of such an infinite matrix by a finite number of its elements depends mainly on the rapidity of the Convergence of the expansion of the angular spheroidal function for one medium in terms of those for another medium.
In order to determine the nature of convergence of such expansion of angular functions, some numerical results are presented. These results should be useful in the final numerical calculation of the field. Numerical results show that the minimum number of terms in the expansion necessary to approximate the function S(c,) in terms of S1ι(c,) within a given accuracy, remains practically the same when S1ι(c,) is also expanded in terms of S(c,).
In the limit of zero eccentricity, expressions for the corresponding radiation problem for spherical geometry are also presented. This result may be applicable to satellite communications. [ABSTRACT FROM AUTHOR]