Zachriel
Posts: 2723
Joined: Sep. 2006
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Some bits from Mendel's Accountant source code.
Offspring:
if(fitness_dependent_fertility) then
fitness_adjusted_offspring = num_offspring*sqrt(post_sel_fitness)
Favorable Mutations:
c... Compute mean absolute fitness effect for favorable mutations.
sum = 0.
d2 = 1.
do i=1,1000000
d1 = d2
d2 = exp(-alpha_fav*(0.000001*i)**gamma_fav)
sum = sum + d1 + d2
end do
fav_mean = 0.0000005*sum*max_fav_fitness_gain
Phenotypic Fitness:
noise = sqrt(geno_fitness_variance*(1. - heritability) /heritability + non_scaling_noise**2)
c... Add noise to the fitness to create a phenotypic fitness score...
do i=1,total_offspring
pheno_fitness(i) = fitness(i) + random_normal()*noise
Unrestricted probability selection:
c... For unrestricted probability selection, divide the phenotypic
c... fitness by a uniformly distributed random number prior to
c... ranking and truncation. This procedure allows the probability
c... of surviving and reproducing in the next generation to be
c... directly related to phenotypic fitness and also for the correct
c... number of individuals to be eliminated to maintain a constant
c... population size.
do i=1,total_offspring
work_fitness(i) = work_fitness(i)/(randomnum(1) + 1.d-15)
end do
Divide by randomnum as well as add non-heritable noise to the phenotype?
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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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