ISSN:0004-9581    

DOI:10.1111/j.1467-842X.1980.tb01159.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryThe problem of testing whether heterozygotes have a selective advantage is considered, assuming the stepwise mutation model for electrophoretic alleles. The population is observed for a number of generations, and the likelihoods of the changes in allele frequencies under the heterozygote advantage model and under the strict neutrality model are compared. It is shown by simulation that statistical tests based on the likelihoods have little power to detect selection if only a few generations of data are available.Many population genetic models, including the stepwise mutation model, have been formulated as diffusion processes in continuous time. The paper gives expressions for the likelihoods of multivariate diffusions observed over a time interval.

ISSN:0004-9581    

DOI:10.1111/j.1467-842X.1980.tb01160.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryThis paper reviews what is currently known about the behaviour of the t‐statistic when one is no longer sampling from a normal distribution. SupposeYis a batch of data on which the t‐test is performed. Briefly then, heavy‐tailed components ofYgive a light‐tailedt, positive correlation amongYgives a heavy‐tailed t, and positively skewed components of Y give a negatively skewedt.The emphasis is on understanding why one gets this type of behaviour, although some numerical tables are presented to illustrate the co

ISSN:0004-9581    

DOI:10.1111/j.1467-842X.1980.tb01161.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryEstimates in simple linear regression which minimize the sum of absolute values of residuals are discussed. These estimates, calledmedian‐estimates, are an analogue of the sample median, and their properties reflect this. A simple graphical procedure, related to an early (1923) one of Edgeworth, is outlined for computing median estimates. This method works well in small or moderate samples, and is demonstrated on two examples. The small sample distribution of the median estimates is examined by conditioning on the pattern of signs of the residuals, and the resulting conditional distribution gives qualitative information on the adequacy of the approximation of the exact distribution by the (known) asymptotic distibutio

ISSN:0004-9581    

DOI:10.1111/j.1467-842X.1980.tb01162.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryAn expression for the exact distribution of the Bell‐Doksum test of independence based upon the use of order statistics from normally distributed random samples is derived and a table of critical values is provided. Two extensions of the theory are considered and possible applications to Poisson processes and queueing theory are note

ISSN:0004-9581    

DOI:10.1111/j.1467-842X.1980.tb01163.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryA test of independence in symmetric bivariate stable distributions is constructed using the empirical characteristic function as a test statistic. A particular class of distributions considered in detail is X = U + V, Y=V+W where U, V, and W are mutually independent symmetric stable distributions with the same index.

ISSN:0004-9581    

DOI:10.1111/j.1467-842X.1980.tb01164.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryA modification of the sequential probability ratio test is proposed in which Wald's parallel boundaries are broken at some preassigned point of the sample number axis and Anderson's converging boundaries are used prior to that. Read's partial sequential probability ratio test can be considered as a special case of the proposed procedure. As far as ‘the maximum average sample number reducing property is concerned, the procedure is as good as Anderson's modified sequential probability ratio tes

ISSN:0004-9581    

DOI:10.1111/j.1467-842X.1980.tb01165.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryAn investigation is undertaken of the logistic regression procedure for estimating the posterior probability of an object belonging to one of two populations. The asymptotic bias and mean square error associated with the procedure are derived for univariate populations whose distributions satisfy the general Day‐Kerridge model for which the logistic form is valid for the posterior probability. These properties are compared with those of the normal discrimination method based on the classical assumption of normal populations with common variances. The asymptotic relative efficiency of logistic regression is considered on the basis of asymptotic mean square erro

ISSN:0004-9581    

DOI:10.1111/j.1467-842X.1980.tb01166.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryA new class of simultaneous bilateral models is introduced to describe spatial dependence on a rectangular lattice. These models, developed primarily for plant competition data, are suitable for small data arrays with sizeable border effects. A maximum likelihood procedure, conditional on fixed border effects, is developed to estimate parameters of such models. Examples are presented for simulated data and for data from a plant competition experiment.

ISSN:0004-9581    

DOI:10.1111/j.1467-842X.1980.tb01167.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SummaryWhen estimating population quantiles via a random sample from an unknown continuous distribution function it is well known that a pair of order statistics may be used to set a confidence interval for any single desired, population quantile. In this paper the technique is generalized so that more than one pair of order statistics may be used to obtain simultaneous confidence intervals for the various quantiles that might be required. The generalization immediately extends to the problem of obtaining interval estimates for quantile intervals. Distributions of the ordered and unordered probability coverages of these confidence intervals are discussed as are the associated distributions of linear combinations of the coverages.

ISSN:0004-9581    

DOI:10.1111/j.1467-842X.1980.tb01168.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY