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### Randomness in Computer simulations

Kendra Sykes

Ashley Savannah

The first computer simulation we looked at "Ant Colonies: Social Organization without a director". There were three types of ants in this colony that did three different types of jobs. The red ants were the foragers, the purple ants were the midden workers and the blue ants were the patrollers. The website provided many simulations that involved these ants but the one that we found most interesting was the simulation that included hydrocarbons.

We found out that hydrocarbon in an ant is a chemical that secrete from their antennae and is modified by their task at hand. When two ants come into contact with one another, one would give off a signal using their hydrocarbon secretion telling what job they are doing which will in turn cause the other ant to switch the job they were originally doing. At the end of this lab, we realized that no matter how many times the ants came into contact with each other, that the ratio of ants (50% forager, 25% midden worker and 25% patrollers) remained constant. We realized that there is not much randomness involved in the work distribution of this colony, that over a period of time, the ratio becomes a constant.

The next computer model that we focused on was called "Virus". In this simulation, we followed the rate in which people were infected by a virus based on the percentage of infectiousness, chance of recovery as well as the duration of interaction. We observed that when the rate of infectiousness was lower than the chance of recovery that more people survived and more people became immune to the virus. But, when the rate of infectiousness was higher than the chance of recovery, more people became infected and eventually died. We feel that this a reflection on real life but is dependant on the type of virus and this makes a significant difference. There are three different types of viruses: if someone comes in contact with HIV, they will most likely get it. If a person gets influenza, they will keep getting it but can recover from it. Then there is the chickenpox, where you get it upon initial contact, but become immune to it there after.