Results 191 to 200 of about 21,896 (225)

The extension of Gompertz law's validity

Mechanisms of Ageing and Development, 1997
The interval 35-85 years is mostly considered as the range of Gomperz law's validity. Looking at the spectrum of causes of death for the interval 10-30 years we find that its main share is caused by various accidents independent of age. These accidents result in the increase and following plateau of the total mortality curve over the age of 15 years ...
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The biological foundation of the Gompertz model

International Journal of Bio-Medical Computing, 1987
The paper examines the biological reasoning of the Gompertz model for tumor growth: the increase and loss rates of the tumor volume are both proportional to the volume itself. The statement is proved mathematically. The theoretical foundation is therefore established, this ensures the application of the Gompertz model as an effective aid for the ...
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Comparison of Entropy Measures for Gompertz and Truncated Gompertz Distribution

Proceedings of the National Academy of Sciences, India Section A: Physical Sciences, 2022
Muhammad Ahsan ul Haq, Muhammad Aslam
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Transforming gompertz's function for fertility analysis: The development of a standard for the relational gompertz function

Population Studies, 1984
Summary The relational Gompertz function improves upon the Gompertz for fertility analysis by achieving a better fit in the tails of the distribution. This is obtained by a transformation of the age scale corresponding to an empirical standard. This standard is developed from Coale and Trussell's model and is appropriate for use with populations of ...
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A Mystery of the Gompertz Function

2006
The Gompertz function describes global dynamics of many natural processes including growth of normal and malignant tissues. On one hand, the Gompertz function defines a fractal. The fractal structure of time-space is a prerequisite condition for the coupling and Gompertzian growth. On the other hand, the Gompertz function is a probability function. Its
P. Waliszewski, J. Konarski
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A stochastic gompertz model with hereditary effect

Journal of Mathematical Biology, 1979
In this paper we have studied a stochastic version of the Gompertz model for population growth of a single species after incorporating the aspect of heredity. Various statistical characteristics--the mean-value function, covariance-kernel, etc.--are evaluated for a delta-correlated process and their asymptotic values obtained.
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Chebyshev approximation by Gompertz function

Matematychni Metody Ta Fizyko-Mekhanichni Polya, 2022
P. S. Malachivskyy, L. S. Melnychok, Ya. V. Pizyur   +2 more
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Calibrating Gompertz in Reverse

2019
This paper develops a computational framework for inverting Gompertz-Makeham (GM) hazard rates, in a manner consistent with a compensation law of mortality for heterogenous populations, to define a Longevity-Risk-adjusted Global (LRaG) Age. To illustrate its salience and relative magnitude, the paper implements and calibrates this framework using rates
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The Gompertz function does not measure ageing

Biogerontology, 2001
The Gompertz transform of the distribution function for the age at death expresses mortality in a form R = R0e(alphat) where R0 is the mortality at time zero and alpha is the rate of increase of mortality, frequently taken as the rate of ageing. The slope of the line alpha is frequently used as a measure of the rate of ageing.
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Gompertz and Gompertz-Makeham Distributions

2007
Albert W. Marshall, Ingram Olkin
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