This book is about how to use new algorithm models to solve complex problems.
The book presents one branch of a field in computer science that we today
call computational intelligence. Big Data play already a great role in society
and evolutionary algorithm may be one approach to do data mining of high-dimensional
data. High-dimensional data are produced in scientific laboratories
all over the world and are often difficult to interpret. Clustering is one possible
technique that may help us to interpret these data.
Clustering is a well-known technique that is used in many areas of science.
This book is about how to use such algorithms to solve clustering of huge sets
of data. This subject may be introduced in the last year at the bachelor level
in computer science or mathematics or at the graduate level. The intention of
the book is to show how to use such computation models on classical clustering
problems. Visualization is an important part of the clustering process. We
therefore also want to visualize the result of the cluster analysis.
The most known clustering algorithm is the K-means algorithm that is dependent
on the parameter value K and the initial position of K cluster centroids. An
incorrect value will result in an inaccurate clustering structure. The configuration
of cluster centroids determines if the algorithm converges to a local minimum
or not. These limitations may be solved by using evolutionary algorithms.
Genetic algorithms and differential evolution algorithms are two paradigms in
the book that are used to optimize the value of K and the initial configuration of
cluster centroids. The correctness and quality of the solution are compared using
both artificial and real-life data sets. Experiments have shown that the algorithms
are able to classify the correct number of well-defined clusters, but fail to
do so for overlapping data clusters. This is mainly because the Davies-Bouldin
Index as a fitness measure has certain kind of limitations. The experiments
carried out in the book also show that both Genetic and Differential evolution algorithms provide suboptimal positions of initial configuration of cluster centroids,
reflected in higher values of the Davies-Bouldin Index.
I will thank Bergen University College for making it possible to write
this book. I also thank Bentham Science Publishers for all help and specifically
Manager for Publications, Salma Safaraz, for all the support during the publishing
process. At last I will thank my prior master student Eirik Steine Frivåg who has
contributed a lot in this book.
Conflict of Interest
The author confirms that there is no conflict of interest to declare for this publication.
Bergen University College
“In memory of my mother, Anna, for
teaching me never to give up.”
List of Contributors
Bergen University College