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Page 35
C0051-01.gif
where M(t, t)is the number of individuals in C0050-02.gif. If we take the ratio C0051-03.gifC0051-04.gif, we have an indication of how close t comes to "extinction" relative to t'(in the sense that extinction occurs when the population produced by t becomes negligible relative to the population produced by t'). If we take the greatest lower bound of this ratio relative to some set of possible plans C0041-05.gif, we have an indication of the worst that can happen to t in E, relative to C0041-05.gif at time t. Continuing in this vein we get the following criterion for ranking plans as to robustness over e:
C0051-02.gif
In effect this criterion ranks plans according to how close they come to extinction under the most unfavorable conditions.
The fantastic variety of possible genotypes, the effects of epistasis, changing environments, and the difficulty of retaining adaptations while maintaining variability (genetic variance), all constitute difficulties which genetic processes must surmount. In terms of the C0051-07.gif framework these are, respectively, problems of the large size of C0021-03.gif, the nonlinearity and high dimensionality of µE,the nonstationarity of µE, and the mutual interference of search and exploitation. The C0051-07.gif framework enables the definition of concepts (chapters 4 and 5) which in turn (chapters 6 through 9) help explain how genetic processes meet these difficulties in times consistent with paleological and current biological observations.
3ec098e70743fcb2f9b43be50b94c009.gif
Summarizing:
3ec098e70743fcb2f9b43be50b94c009.gif
C0021-03.gif,populations of chromosomes represented, for example, by the set of distributions over the set of genotypes C0039-11.gif.
3ec098e70743fcb2f9b43be50b94c009.gif
W,genetic operators such as mutation, crossover, inversion, dominance modification, translocation, deletion, etc.
3ec098e70743fcb2f9b43be50b94c009.gif
C0041-05.gif, reproductive plans combining duplication according to fitness with the application of genetic operators; for example, if each operator C0051-08.gif is applied to individuals with a fixed probability pi, then the set of possible plans can be represented by the set
3ec098e70743fcb2f9b43be50b94c009.gif
C0051-05.gif
3ec098e70743fcb2f9b43be50b94c009.gif
e, the set of possible fitness functions C0051-06.gif, each perhaps stated as a function of combinations of coadapted sets.

 
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