Elitism is a genetic-algorithm survivor-selection method that preserves the highest-fitness individuals from the existing population and newly generated offspring. It protects the best solutions from being lost, but applies the highest selective pressure and can reduce diversity. section 7.3.3 section 7.3.5
Apply elitist selection by following these steps:
- Combine the old population with the new offspring. section 7.3.5
- Rank the combined individuals by fitness and select the best candidates for the next population. section 7.3.5
- Tune the number of preserved individuals carefully: preserving more elites lowers the succeeding population’s diversity and can encourage premature convergence. section 7.3.3
Ticket-pricing population
Among old candidates with objective values 8,820, 84,420, 90,000, 128,500, and 18,000, the best old solutions are retained. Offspring with values 20,980 and 76,420 can also enter the next population when they outrank weaker old individuals; the resulting selected set contains candidates ranked 1 through 5 from both groups. section 7.3.5

