“The second problem in MacKay’s analysis is that he assumes sexual mating occurs at random. It is easy to give a counterexample to his bound in a society where people choose mates wholly on the basis of their fitness (i.e. in his model distance from the ideal bitstring).”
Logicnazi, Eliezer’s model may do that somewhat and would be easy to adapt to do what you want.
I don’t know python, so I may be wrong when I suppose that the children in his model come out sorted. The next generation they receive a random number of mutations, typically 10, and then the ones that are side-by-side are mated and assorted. The number of new mutations they get is random but the number of old mutations they already had may be ordered—maybe the ones that were most fit at that point are the ones that mate together, and the ones that were least fit, and so on. To do complete sexual selection based on perfect knowledge, you could simply sort the parents after their mutations and then it ought to work your way. One simple extra step.
The point of MacKay’s toy model is that it displays results people were already arguing about. He designs it to show the results he wants. So he does truncation selection—probabilistic selection would be slower. He has his genes assort with no linkage. In all the most basic ways he makes the choice that should result in the most effective selection. He does not do sexual selection based on fitness, probably because readers would call foul. It isn’t clear that humans can judge fitness with 100% reliability, much less rotifers or yeast cells. Sometimes mating might be closer to random.
“The second problem in MacKay’s analysis is that he assumes sexual mating occurs at random. It is easy to give a counterexample to his bound in a society where people choose mates wholly on the basis of their fitness (i.e. in his model distance from the ideal bitstring).”
Logicnazi, Eliezer’s model may do that somewhat and would be easy to adapt to do what you want.
I don’t know python, so I may be wrong when I suppose that the children in his model come out sorted. The next generation they receive a random number of mutations, typically 10, and then the ones that are side-by-side are mated and assorted. The number of new mutations they get is random but the number of old mutations they already had may be ordered—maybe the ones that were most fit at that point are the ones that mate together, and the ones that were least fit, and so on. To do complete sexual selection based on perfect knowledge, you could simply sort the parents after their mutations and then it ought to work your way. One simple extra step.
The point of MacKay’s toy model is that it displays results people were already arguing about. He designs it to show the results he wants. So he does truncation selection—probabilistic selection would be slower. He has his genes assort with no linkage. In all the most basic ways he makes the choice that should result in the most effective selection. He does not do sexual selection based on fitness, probably because readers would call foul. It isn’t clear that humans can judge fitness with 100% reliability, much less rotifers or yeast cells. Sometimes mating might be closer to random.