Biometrika

最新文章

• Note on discriminant functions AI翻译
  作者：Welch, BL
  摘要：The problem of discriminating between two specified populations is discussed.
• On some properties of normal distributions, univariate and bivariate, based on sums of squares of frequencies AI翻译
  作者：Yule, GU
  摘要：If the distribution of a normal variate has standard deviation [sigma] and the total integral [image] ydx is N1, y2 has also a o normal distribution with standard deviation [image]and integral [image]. This suggests that, if N2 is the sum of squares of class frequencies, a good estimate for [sigma] might be [image],N1 being of course the sum of class frequencies. [sigma] and [sigma]e are compared for several series of statistics; their agreement is an inadequate test for normality. An example ...
• Bright's disease, nephritis and arterio-sclerosis - A contribution to the history of medical statistics AI翻译
  作者：Greenwood, M; Russsell, WT
  摘要：Bright''s disease was chosen for study, partly because it is of interest in itself, partly as a characteristic example of a recorded rate of mortality in which it was a priori certain that changes of opinion had been an important factor of statistical variation. It seems that the statistical data of different generations cannot, by any practicable reclassification, be rendered sufficiently comparable to permit of any sound inferences as to whether the factors favoring Bright''s disease did rea...
• The London skull AI翻译
  作者：Young, M
  摘要：The London skull was discovered in 1925 at a depth of 42 ft. during the excavations for Lloyd''s new building in the City of London. The age of the deposit in which the skull lay has been the subject of much discussion but the most recent investigations seem to indicate that the presumptive age of the skull must be at least Aurignacian and very possibly older (Mousterian or pre-Mousterian). The skull is very incomplete and comprises merely the occipital and left parietal bones in almost their ...
• A new measure of rank correlation AI翻译
  作者：Kendall, MG
  摘要：A coefficient is proposed for the measurement of the relationship between 2 rankings of the same set of objects. The coefficient is easy to calculate and has a natural interpretation. To permit a judgment of significance the distribution is given of the values of the coefficient obtained by correlating a given ranking with all possible rankings. The distribution tends rapidly to normality as the number of ranks increases.
• Description of nine human skulls from Iran excavated by Sir Aurel!Stein, KCIE AI翻译
  作者：Morant, GM
  摘要：Measurements, descriptive remarks and photographs are provided. The specimens came from 3 widely separated districts one is modern and the others are believed to be of late prehistoric date. The modern skull differs appreciably from the others in type, but this and previously published skeletal material from Iran is too scanty to yield any safe conclusions regarding the racial history of the country.
• On tests for homogeneity AI翻译
  作者：Welch, BL
  摘要：Results are obtained throwing light on the range of applicability of the normal theory distribution of the correlation ratio to cases where the normal theory conditions are not satisfied. The index of dispersion used to test the homogeneity of binomial series is treated as a special case. A procedure is suggested for dealing with the situation where the x2 distribution can no longer be applied owing to the smallness of the sample sizes.
• Heterostylism in natural populations of the Prunrose, Primula acaulis AI翻译
  作者：Haldane, JBS
  摘要：The ratio of thrum to pin plants among 2302 primroses did not differ significantly from equality. Individual populations did not diverge from equality to a significantly greater extent than could be expected as the result of sampling error.
• A new method of experimental sampling illustrated on certain non normal populations AI翻译
  作者：Hey, GB
  摘要：Sampling is effected by punching both original data and random numbers on to Hollerith cards. Sorting and tabulating machines take random samples and compute the various statistical parameters for each sample with great speed. The method is used to demonstrate on certain non-normal populations, both actual and artificial, that the distribution of the estimates of the correlation and regression coefficients in samples from a bi-variate population where the correlation is high, is not seriously ...
• Certain statistical problems arising in plant breeding AI翻译
  作者：Tang, Y
  摘要：The author considers from the statistician''s point of view the problem of breeding new vars. of sugar beet. The breeder, with the purpose of increasing the sugar content, has to make a selection of vars. from a larger supply, multiply the seeds of those selected and compare them in field trials with some established standard. For economic reasons the breeder must ask: (1) whether he should select more vars. and, consequently, test them with fewer replications, or vice versa; and (2) what is t...