1.5 This Book 9
• Chapter 4 present strategies for overcoming local optima in order to approximate
the global one, or at least to find as many local optima as possible. Strategies
comprise restarts, niching, fitness sharing, and novelty search.
• Chapter 5 gives an introduction to constraint handling. Practical optimization prob-
lems are often constrained. Not the whole solution space is allowed, but only a
feasible subset. Genetic Algorithms have to be adapted to cope with constraints.
One strategy is to choose representations and operators that avoid infeasible solu-
tions. An easy way to cope with constraints is the use of penalty functions, which
deteriorate the fitness of a solution.
• Chapter 6 presents multi-objective optimization approaches. Multiple optimiza-
tion goals induce multiple objectives. If they are conflictive, the minimization
of one objective results in the maximization of another. Strategies like the non-
dominated sorting Genetic Algorithm, rake selection, and selection based on
the hypervolume indicator allow the approximation of a Pareto-set of solutions.
• Chapter 7 gives an introduction to theoretical research on Genetic Algorithms.
Starting with an overview of theoretical research in this area, a runtime analysis
is exemplarily presented and an overview of further theoretical tools is presented.
• Chapter 8 presents research in the intersection between machine learning and
Genetic Algorithms. Machine learning algorithms can be used to improve and
support genetic search. Examples include covariance matrix estimation, meta-
modeling, and visualization. Genetic Algorithms are effective tuning and learn-
ing approaches for machine learning problems.
• Chapter 9 shows Genetic Algorithms in various applications. Genetic Algo-
rithms can be used to optimize machine learning problems, to optimize wind tur-
bine locations considering wake effects and geo-constraints, to scale the features
of wind power data in nearest neighbor regression, and to optimize rule bases for
virtual power plants.
• Finally, Chap. 10 closes with a summary of the most important aspects and con-
tributions of this book.
The book closes with a summary and an appendix containing supplementary infor-
mation.
1.6 Further Remarks
This depiction passes on complex notations where possible. Although a thorough
mathematical formulation might be much more exact helping to implement and
model certain aspects and details, it also can complicate the understanding of con-
cepts, the context, and the connections between different mechanisms. However, here
is some basis notation that we usually employ in our depictions. A vector is a bold
small letter x while a scalar is written with a small plain letter.
Also the pseudocode of most algorithms presented in this book passes on com-
plex notations. More important than the interpretation of possibly arbitrary levels of