George M. Tallis

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In the companion paper (Tallis and Leppard 1988) (T&L) , the joint effects of selection and assortative mating on a single polygenic character were examined. It is the purpose of this paper to extend the results to multiple characters. The same structure and notation will be used as in T & L, with the exception that the treatment allow for q >=1 characters.(More)
An n-generation pedigree is set up and selection is carried out generation by generation. The influence of this procedure on the covariances in subsequent generations is assessed and, ultimately, Bulmer's general recursion formula for the reduction in genetic variance due to selection is obtained. The results are extended to assess the effect of selection(More)
In two previous papers (Tallis 1985, 1987), the effects of assortative mating ("assortation") and selection on additive genetic variances and covariances were examined. The arguments were sufficiently gneral to allow for the simultaneous treatment of several characters. It is the purpose of this paper to extend this work by developing results which allow(More)
We present analyses for survival data obtained from a central cancer registry with passive follow-up. This method of data collection has the potential to produce unknown random losses which would affect estimates of survival. We show that non-parametrically estimated conditional distributions remove any effect of these unknown losses and that a compound(More)
This paper illustrates many of the concepts and issues relating to breast cancer screening by reference to a case study of screening in South Australia and by a survey of the mathematical screening models. This work is motivated by the observation that, for some women, the prospects for a breast cancer cure appear to be enhanced if the disease is detected(More)
This paper introduces the concept of a transfer system of random variables and uses it ot study various types of assortative mating. The standard correlation structure between relatives under phenotypic and genetic assortative mating are obtained easily and these results are then extended to multiple characters by means of multivariate transfer systems.(More)
A random sample of death records of adult males from the period 1967 to 1970 was chosen from the South Australian Registry of Births, Deaths, and Marriages. The natural parents of these individuals were identified by cross-referencing to birth certificates, and an extensive search was made of the death records for these parents. In this manner random(More)
BACKGROUND In 1989 BreastScreen SA started screening for breast cancer in South Australia. METHODS The programme concentrated on women between the ages of 50 and 69, using a 24-month screening interval and a joint method of mammography, clinical examination and self-detection. RESULTS This paper is a summary of our efforts to provide an assessment of(More)