What are the different low-level operators in Genetic Algorithm?

For my exam, I开发者_运维问答 want to elaborate on different Low-level GA operators. But I found different texts says about different Low-level operators.

Genetic Algorithms in Search, Optimization, and Machine Learning by David E. Goldberg lists

• Dominance
• Inversrion
• Intra chromosomal duplication
• Deletion
• Translocation
• Segregation

as low-level operators.

And lists migration, marriage restriction and segregation as higher level population oriented operators.

But some other texts like Neural Networks, Fuzzy Logic and Genetic Algorithms: Synthesis and Applications by S. Rajashekaran and G.A. Vijayalksmi includes migration in low-level operators.

What is the difference between this low-level and high-level operators.

Goldberg's low-level operators alter how children are formed from the parents, and the high-level operators are modifying how selection chooses the parents. Defining migration as a low-level operator does not make sense under that definition, what other examples/definitions do Rajashekaran and Vijayalksmi give?