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作者：KENDALL, DG
摘要：The birth-and-death stochastic process introduced by W. Feller (Acta Biotheoretica, 1939) describes growth of a population under simplified laws of reproduction and mortality. One simplification is that chances of both are completely independent of the previous history of the individual, including elapsed time since his own birth. This assumption implies that the stochastic dependence of population size on time is given by a discontinuous Markoff process. The author claims, however, that this ...
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作者：JONES, AE
摘要：The problem of estimating the mean value of a random variable along a continuous strip of finite length is considered for the case in which the autocorrelations decay exponentially. It is shown that if the serial correlation is appreciable or if the sample is large the best systematic arrangement is a measurement at the centers of equally spaced intervals. The 2d paper points out that this result is valid only in the case considered and that for other autocorrelation schemes, this arrangement ...
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作者：ORCUTT, GH; JAMES, SF
摘要：Prior investigation of 52 economic time series indicated they might have been drawn from a population of series generated by [PSI]t+1=[PSI] t + .3([PSI]t- [PSI]t-1) + [epsilon]t+1, where [epsilon] is random in time with expected value of zero. Using this model, a set of non-related series were constructed and correlations between them were computed. Empirical investigation indicates that significance tests may be devised by computing the approx. variance of the correlation r between 2 unrelate...
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作者：ANSCOMBE, FJ
摘要：Transformations having the effect of approx. normalizing Poisson, binomial and negative-binomial variables are given to within a constant appearing in each transformation. Optimum values of the constants are defined as those which make the variance of the transformed variable most nearly constant, with obvious application in the technique of analysis of variance. Asymptotic formulae are given for the first four moments and for the efficiency in estimation of the original parameters for transfo...
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作者：GODWIN, HJ
摘要：A recurrence relation is derived to make possible calculation of the moments of the distribution of the mean deviation from the mean of a sample of n from a normal population. The first 4 moments agree essentially with those reported by Geary; a new 5th moment is given. Two functions of m which are distributed more nearly normally than m itself are obtained and their means and standard deviations given.
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作者：MORAN, PAP
摘要：Exact values of the first 3 moments are obtained for the serial coeff., [image] and for the cyclical coeff., [image] with Xn+1 taken equal to Xi, under the assumption that the Xi are actually uncorrelated and have the same normal distribution. In the case that the mean of the time series is known as well, the definitions of the 2 coeffs. are modified in an obvious manner and the first four moments of each is given. Some mention is made of the serial coeff. when s units separate paired measurem...
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作者：COX, DR
摘要：Three asymptotic distributions, one of which is new, are discussed for the case of samples from a symmetric unimodal distribution. Gumbel''s distribution (Ann. Math. Stat., 1947), in terms of a modified Bessel function of the second kind appears to be least accurate. Cox''s distribution is of the form [image] where [PHI] (x) and [PHI] (x) are the frequency and distribution functions of the basic symmetrical distribution with mean zero, and wn is the sample range. This distribution is obtained ...
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作者：PEARSON, ES; MERRINGTON, M
摘要：Various problems lead to analysis by 2 x 2 tables. The one considered here is that in which two treatments, the old (or no) treatment A and the improved treatment B are each given to half of a sample of N individuals such that X of the N would react favorably if given either treatment, Y if given treatment B, and Z would not react to A or to B. The hypothesis Y = 0 is to be tested against alternatives Y>0. The data are observed in the form of a 2x2 table, [image] The appropriate test is whethe...
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作者：BROWNLEE, KA; LORAINE, PK
摘要：Constructions are given for completely orthogonal squares of side,any prime number or 4 or 8. It is pointed out that these make possible introduction of n + 1 factors all at n levels in an expt. involving n2 plots, but that all degrees of freedom for one main effect are confounded with 1st-order interactions. Orthogonal constructions in 3 and more dimensions are given, together with the properties of the corresponding exptl. designs.
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作者：LESLIE, PH
摘要：Previous work on a matrix representing a system of age-specific fertility and mortality rates is extended and amplified. The methods developed are applied to the detn. of the stable female birth-rate and what R. A. Fisher has called the total reproductive value of a population. The predator-prey relationship between 2 populations is also discussed.
