DRILL Answer the following questions about yesterdays activity

DRILL Answer the following question’s about yesterday’s activity in your notebook: 1. 2. 3. 4. Was the activity an example of ACO or PSO? What was the positive feedback? What was the negative feedback? How did we build in fluctuations?

Swarm Theory: “The Wisdom of Crowds” Creating a Swarm

Swarm Intelligence • Swarming is a behavior that describes how a group of individual animals/objects move together in the same direction all at once. “A flock of seagulls. ” “A school of fish. ” “An army of ants. ” • Swarm Theory is the modeling and simulation of the collective behavior of groups of simple agents.

Models for Swarming Behavior “The whole than which the sum of each part. ” How is dogreater we choose to use? “Solve complex problems using simple agents. ” Ant Colony Optimization (ACO) Particle Swarm Optimization (PSO) Ants are great finding the • Works best for at finding closest source of food discrete solutions • Ants use pheromones to communicate information • Birds Worksare best excellent for finding at finding continuous multiple sources solutions of food simultaneously • Birds broadcast information locally

Swarm Theory: Setting it up To solve a problem using swarming techniques you will have to: 1. 2. 3. 4. Define the domain Create an algorithm Write instructions for the agent Define the criteria for completion

Swarm Theory: Setting it up Domain Algorithm Threshold Agent

Defining the Domain – the set of all possible input values to a function. • • Spatial – a specified region of space Temporal – a period of time Other Combination What was the domain in yesterday’s activity? Problem: Find the nearest, least expensive gas station to Poly. Problem: Choose the most reasonable five homework Domain: All gas stations within a 1 mileofradius of Poly. sets. Domain: The five homework sets.

Creating an Algorithm – a step by step procedure for solving a problem, usually iterative “Choose Homework” 1. 2. 3. 4. Positive Feedback Negative Feedback Fluctuation Multiple Interactions Amplifies good solutions –> Dancing Stabilizes past the system –> Erasing Mimics nature # –> Random –> Iteration

Building the Agent Each agent in a swarm is given a set of simple instructions that require it to search the domain, test its surroundings and communicate results. “Choose Homework” 1. 2. 3. 4. Explore and look for possible solutions Inspect solution Return and communicate results Wash, rinse, repeat…

Swarm Theory • Homework: – Read over tomorrow’s lecture (U 1 L 4. ppt) • Pop quiz is possible – Set up a swarm intelligence to solve this problem: • A nest of ants are looking for food in a large field that is divided up into a 8 x 8 grid. In one of the grids are balls representing food. The food can only be “found” if an agent enters a grid space adjacent to the food. What is the shortest route to the food?

Swarm Theory Ants(A) are looking for food(F) in a large field that is divided up into a 8 x 8 grid. In one of the grids are balls representing food. The food can only be “found” if an agent enters a grid space adjacent to the food. What is the shortest route to the food? 1. Define the domain 2. Create an algorithm 3. Write instructions for the agent 4. Define the criteria for completion F A