02/03/07DePaul University, HON2071 Evolutionary Computation Module for HON207

02/03/07DePaul University, HON2072 Introduction This lecture is an introduction to the topic of Evolutionary Computation, but it is not a substitute for the assigned readings We will review key concepts, and we will introduce a few simple models in R

02/03/07DePaul University, HON2073 Topics What is Evolutionary Computation (EC)? Basic principles Fitness Simple models of asexual reproduction Description of the R programs needed for the assignments

02/03/07DePaul University, HON2074 What is Evolutionary Computation (EC)? EC is an emerging field that focuses on the design and application of computational models inspired in Darwinian-like formulations.

02/03/07DePaul University, HON2075 The goals of EC Developing and understanding better models of natural evolution Engineers try to use evolution principles to build artifacts (e.g., a stock trading tool) Artificial-life researchers experimenting with artificial evolutionary worlds

02/03/07DePaul University, HON2076 Basic Concepts Evolution in a Darwinian sense. Individuals in Population(s) compete for limited resources. Dynamically changing populations due to death/birth Offspring resembling parent but not identical

02/03/07DePaul University, HON2077 Genotype / Phenotype The genotype is the specific genetic makeup (the specific genome) of an individual, in the form of DNA. The phenotype of an individual organism is either its total physical appearance and constitution or a specific manifestation of a trait. For our purpose, we will assume a one-to-one correspondence between the two.

02/03/07DePaul University, HON2078 Gene/Pheno Space The geno/pheno space is a vector that specifies the genetic makeup of an individual. In Genetics, an allele is any one of a number of viable DNA codings. In other words, the possible values for the elements in the vector (e.g., a number between 0 and 5)

02/03/07DePaul University, HON2079 Fitness In biology fitness is, in general, an ex post facto measure based on the individual’s ability to survive and reproduce. This could be related to the environment, the make up of the population, etc. In our simplified models, fitness will be a function solely of individual’s geno/phenotype. e.g., f(x)=50-x 2

02/03/07DePaul University, HON20710 Mutation In biology mutations are changes to the genetic material We need to make some assumptions on how likely mutations would be in our model, and how would those mutations be implemented If there are L genes, we assume a probability of mutation = 1/L The mutation would be the value in the gene inherited from the parent 

02/03/07DePaul University, HON20711 First simulation 1.3 EV on a Simple Fitness Landscape (page 6) Fitness function f(x)=50-x 2 1 trait Mutation: change by  = 1 Population = generations

02/03/07DePaul University, HON20712 First simulation 1.3 EV on a Simple Fitness Landscape (page 6) Fitness function f(x)=50-x 2 1 trait Mutation: change by  = 1 Population = generations We have a function in R that can do this: EC(M,L,generations,lb,ub,formula,mutrule, Delta,fix)