Genetic Algorithms, Fuzzy Logic

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Genetic Algorithms, Fuzzy Logic Intelligent
Agents

• Presented By
• Dog Gone I.T.
• Lance Peiper
• Liz Cooksey
• Josh Berwald
• Eric Rowe
• Jill McClain

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What is an Algorithm?

• A set of instructions that is repeated to solve a
  problem.

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What are Genetic Algorithms?

• Software programs that learn in an evolutionary
  manner, similarly to the way biological systems
  evolve.
• Simply, it is a search method that follows a
  process that stimulates evolution in a computer.
• Survival of the Fittest solution.

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Process of a Genetic Algorithm
Start
Describe Problem
Generate Solutions
Stop
Yes
Is it good enough?
Step 1 Step 2 Step 3 Step 4 Step 5
NO
Select best parents to reproduce
Create a set of offspring
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First Step

• When given a problem
• Describe it
• Generate a Solution - represented as a
  chromosome (string of genes)
• Test the Solution
• If it is the best, then STOP.
• If it is not good enough, go to Step 2..

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Step 2

• Reproduction
• Select parents (solutions) with a max. fitness
  function to produce offspring
• Fitness Function - measure of the objective to be
  obtained
• Parents can also be chosen by random selection
• Result - a new generation of solutions

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Step 3

• Crossover Process
• Choosing a random position in the string and
  exchanging the segments by either moving it left
  or right with another string

Step 4

• Creation of new offspring

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Step 5

• Apply random mutation
• an arbitrary change in a situation (string)
• used to prevent the algorithm from getting
  stuck

Repeat to Step 1
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Genetic Algorithm Example

• Secret Number 001010
• Random Trial and error 32 guesses (avg)
• Genetic Algorithm Solution
• Guess 4 numbers (each candidate solution is
  called a chromosome)
• (A) 110100 1 digit correct ?Delete
• (B) 111101 1 digit correct ?Delete
• (C) 011011 4 digits correct
• (D) 101100 3 digits correct
• For C D Mate the parents genes by splitting
  each number
• C) 011011 D) 101100
• Crossover to create offsprings combine 1st part
  of C with 2nd part of D and vice versa
• E) 011100 - score 3 F)101011 - score 4 (new
  generation)
• Offsprings not much better than parents. Mate
  and crossover parents with new split
• C) 011011 D) 101100
• G) 011000 score 4 H) 101111 Score 3
• Select best couple out of C H. Number of
  different options (eg. CF or CG, GF). Mate
  and crossover
• F) 101011 G) 011000 ? I) 111000 score 3
  J) 001011 score 5
• F) 101011 G) 011000 ? k) 101000 score
  4 L) 011011 score 4
• Mate and crossover with J and K as parents

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Parameters to Set

• Number of initial solutions to generate
• Number of offspring to generate
• Number of parents and offspring to keep for the
  next generation
• Mutation probability (very low)
• Probability distribution of crossover point
  occurrence

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Parameters to Set (cont.)

• Parameters depend on problem being solved
• Determined by trial and error

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GA is used in..

• Dynamic Process Control
• Simulation of models of behavior and evolution
• Complex design of engineering structures

• Pattern Recognition
• Scheduling
• Transportation and Routing
• Layout and Circuit design
• Telecommunications

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GA Software

• Evolver (Excel add-in)
• Genetic Algorithm User Interface (Adaptive
  Software www.gaui.com)
• XperRule GenAsys - an ES shell with an embedded
  genetic algorithm

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Fuzzy Logic

• Uncertainty
• Accurate way to describe human decision making
• Thinking isnt always true or false
• Involves the gray areas
• Allows computer to be less precise

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Examples of Fuzzy Logic

• Anti-lock brakes may lock by sensing 18 different
  factors
• Fuzzy logic washing machines use three inputs and
  sensors to adjust the load parameters and time to
  wash and rinse
• Fuzzy logic vacuums monitor the surface and the
  condition of the material and adjust
  automatically.

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Advantages

• Provides flexibility
• Provides options
• Allows for observation
• Increases the systems maintainability
• Controls situation not easily defined by
  mathematical solutions

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Intelligent Agent (IA)

• A computer program that helps a user with routine
  computer tasks
• Relatively new technology
• Several definitions and fluctuating capabilities
• Overcome information overflow on the internet

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Intelligent agents

• Assists user with tasks such as searching
• agents decide what is relevant to user
• Filters data, identifies relevant sources of data
• Agent is autonomous
• Goal oriented
• Flexible
• Self-starting

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Autonomy

• Example- Science Experiment
• User Specifies
• Needs- find journal articles about experiments in
  a specific field
• Constraints- a certain experimental system or
  reactant/reagent was used
• And preferences- articles are written by research
  groups at major universities
• Agent then makes various decisions based on
  parameters set- they dont need constatn user
  input.

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Autonomy

• Autonomy provides time saving capabilities
  because it works for the user when the user isnt
  directly in control. Too much autonomy can be
  problematic. A good agent needs to find the right
  level of autonomy for the task at hand.

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IA applications

• Building communities
• Match people based on preferences
• Use criteria such as musical tastes, books,
  investment analysis, etc.
• Agents, inc

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Research, analysis, news

• Reduces information overload
• Saves search time
• Who has most/best content
• Altavista- advanced searching
• Farcast- custom news
• IBM infomarket

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Products and services

• Value added tools
• Finds products and services from company
  databases
• Returns product descriptions and prices
• Vendors pay to be included
• Fido the shopping doggie

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Evolver
Evolver is an optimization add-in for Microsoft
Excel. Evolver uses innovative genetic algorithm
(GA) technology to quickly solve complex
optimization problems in finance, distribution,
scheduling, resource allocation, manufacturing,
budgeting, engineering, and more.
http//www.palisade.com/html/evolver.html
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Tutorial

• Presented By
• Dog Gone I.T.
• Lance Peiper
• Liz Cooksey
• Josh Berwald
• Eric Rowe
• Jill McClain

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First Things First

• Download Evolver 4.0 Demo from
• http//www20.brinkster.com/mist5620
• Also download tutorial slides and tutorial excel
  files
• Install Evolver and extract tutorial files
• Start ? Programs ? Palisade Decision Tools ?
  Evolver 4.0 for Excel

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Display Watcher
Start Optimization
Start Evolver
Evolver Settings
Stop Optimization
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Evolver Settings

• Select the target cell the cell that you are
  trying to maximize, minimize, or get close to a
  particular value.
• Add adjustable cells the cells that Evolver
  will adjust to try and find the optimal solution.
• Define constraints constraints are conditions
  that must be met for a solution to be valid.

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Target Cell
Add Adjusting Cells
Add Constraints
Options Dialog
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Add Adjusting Cells
Choose Solving Method
Adjustable Cell Range
Minimum Cell Value
Maximum Cell Value
Allow Only Integers
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Solving Methods

• Recipe variables can be combined independently
  like ingredients in a recipe.
• Order used when you are trying to arrange a set
  of given values into a particular order.
• Grouping variables are combined into groups
  where the number of groups equals the number of
  unique numbers.
• Budget similar to the Recipe method except that
  you are shooting for a summed target goal.
• Project used mainly for project management
  where items must be completed in a particular
  order.
• Schedule similar to the Group method but
  assigns each variable to a unit of time.

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Adding Constraints

• Hard Constraints conditions that must be met
  for a solution to be valid. Solutions that dont
  meet the constraint will be thrown out.
• Soft Constraints conditions that we would like
  to meet but the solutions are not thrown out it
  the condition is not met.

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Evolver Options
Updating the display
Graph Progress Option
Stop after so many trials or after so many minutes
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Dog-Gone I.T.

• Thanks!
• Any questions?