Zachriel
Posts: 2723
Joined: Sep. 2006
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| Quote (Steve Schaffner @ June 18 2009,20:53) | <snipped>
And the whole thing is pretty convoluted, when the essence of the model could be captured simply by assigning a fitness to the genotype and then calculating the number of offspring. |
From much of this discussion, it's easy to see how many different ways there are to abstract an evolutionary process.
These are the primary attributes I've found in Mendel's Accountant:
* Population of Genotypes (genotypic fitness).
* Genotype modified by heritability and noise to Phenotype (phenotypic fitness).
* Genotype further modified for chance of reproductive success to Working Fitness.
* Number of offspring proportional to sqrt(Phenotype).
* Reproduction with mutation.
* Throw in more random factors, such as random death.
> The calculation of Phenotype is not scaled.
> The calculation of Working Fitness is division by Randomnum. Not the sqrt(randomnum), not some other exponent. Or even a normal binomial to determine reproductive success.
> Number of offspring proportional to sqrt(Phenotype). Why the square root? Why not some other exponent?
> Random death? Isn't that already accounted for in phenotypic fitness (for stillbirths) or chance of reproductive success?
You may as well throw in another factor that randomizes falling off a cliff and whether she has a headache, and just make up numbers or exponents or parameters that seem right. The problem is the qualitative nature of the simulation and the arbitrariness of some of the assumptions. I just don't see Mendel's Accountant being salvageable as a quantitative model of biology.
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You never step on the same tard twice—for it's not the same tard and you're not the same person.
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