Lecture 22

• Lecture 22
  • Video
  • Genetic Algos
  • Stochastic Operators
  • Metaphor
  • Algorithm
  • MAXONE Problem
  • Methods of selection
  • Methods of reproduction
  • Crossover strategies

Video

link

Genetic Algos

Stochastic Operators

• stochastic bolre bcz probabilistic hai saare yeh

Metaphor

• computer model introduces simplifications(relative to real biological mechanisms) but surprisingly complex and interesting structures have emerged out of evolutionary algos

Algorithm

• trying to create a population which is more fitter

MAXONE Problem

• maxmize # of ones in a string of L binary digits

• we also decide what kind of crossover
  • single point crossover
• probabilistic nature of crossover

• calculate fitness agin, increased

• what is stopping criteria?
  • fitness reached itni value?
  • itna percentage improvement a gaya..

Methods of selection

• roulette-wheel
  • each individual gets a slice of wheel but mroe fits get larger slices than lesser fit ones
  • 
• etilist
  • choose only most fit memebers of each generation (top 5/6)
• fitness-proportionate
  • select only those that are above ceratin cutoff of target fn (fitness > 6 say)
• scaling
• rank

Methods of reproduction

• crossover
• mutation

Crossover strategies

• randomly select a single point for crossover
• multi point crossover
• uniform crossover