997 resultados para Billingsley, William Newton, 1853-1912.


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The central question addressed in this paper is to what extent the influence of social origin on life chances has changed over time for both men and women. In order to capture this change, intergenerational social mobility of eight different birth-cohorts, covering most of the entire twentieth century, is analysed using a unique collection of twelve Swiss national population sample surveys. The main results show that social mobility has remained constant across cohorts born in 1912 and those born in 1974. This suggests that unlike some other industrialised countries, inequality based on social origin is persistent in Switzerland.

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Biochemical systems are commonly modelled by systems of ordinary differential equations (ODEs). A particular class of such models called S-systems have recently gained popularity in biochemical system modelling. The parameters of an S-system are usually estimated from time-course profiles. However, finding these estimates is a difficult computational problem. Moreover, although several methods have been recently proposed to solve this problem for ideal profiles, relatively little progress has been reported for noisy profiles. We describe a special feature of a Newton-flow optimisation problem associated with S-system parameter estimation. This enables us to significantly reduce the search space, and also lends itself to parameter estimation for noisy data. We illustrate the applicability of our method by applying it to noisy time-course data synthetically produced from previously published 4- and 30-dimensional S-systems. In addition, we propose an extension of our method that allows the detection of network topologies for small S-systems. We introduce a new method for estimating S-system parameters from time-course profiles. We show that the performance of this method compares favorably with competing methods for ideal profiles, and that it also allows the determination of parameters for noisy profiles.