Results 231 to 240 of about 2,986,773 (268)
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Population size and rate of evolution
Journal of Molecular Evolution, 1972It is suggested that in evolution there is much substitution of nearly neutral mutations, for which the selection intensity varies from time to time or from region to region. Since the variance among the selection coefficients of new mutants decreases when the environment becomes uniform, the probability of a mutant being advantageous to the species as
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The Effective Size of Fluctuating Populations
Theoretical Population Biology, 2001We consider a Wright-Fisher model whose population size is an autocorrelated stochastic process. Our interest is in the effects of autocorrelated fluctuations of the population size on the effective size. We define the inbreeding effective size and the variance effective size and show that these effective sizes are the same for this model.
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The Effect of Mutation on Population Size
Nature, 1973AFTER the work of Haldane1 and Muller2, much has been written about the genetic load caused by mutation. This mutational load had been defined as the fraction by which the mean fitness of a population subject to mutation differs from the fitness of the wild (non-mutant) genotype3. The operational definition of load is then
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Rawlsian optimal population size
Journal of Population Economics, 1993"In this paper, I examine the implications of the Rawlsian maximin criterion for optimal population size and intergenerational allocation of resource when fertility is endogenous. I show that whenever children are better-off than their parents in laissez-faire, then the size of the population and parental bequests are also optimal according to the ...
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Population Size and Extinction: A Note on Determining Critical Population Sizes
The American Naturalist, 1985On presente divers modeles de probabilite d'extinction des populations, avec l'exemple particulier d'Ursus arctos, espece menacee.
Mark L. Shaffer, Fred B. Samson
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On the minimum size of endogamous populations
Social Biology, 1976Abstract The survival of small endogamous human populations is investigated by computer simulation. It is shown that (1) populations practicing strict monogamy with no extramarital pregnancy are less likely to survive as endogamous groups than are those in which marriage is not a prerequisite for childbearing ; (2) low fertility—low mortality ...
J W, MacCluer, B, Dyke
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Sequential Estimation of the Size of a Population
Biometrika, 1972When estimating the size of a finite population, it is possible to consider, as an alternative to the capture-recapture method, a sequential scheme. Suppose an urn contains an unknown number, N, balls, initially all white. A single ball is drawn at random and if it is white it is painted black and returned to the urn, while if it is black, indicating ...
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Population Size In Classifier Systems
1988Abstract The question of optimal population size in Learning Classifier Systems is analyzed empirically in this paper. Classifier Systems are rule-based systems that use Genetic Algorithms, a model of natural selection and genetics, as their principal learning mechanism, and an economic model as their principal apportionment of credit mechanism. *CFS
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