Excel Homework

Zan Lowe-Skillern Excel Homework 1) a. For the SIR linear model, the two variables, susceptible and infected, were inversely proportional. We started out with the whole population of a school being healthy except for one person. Over the course of the model, this one infected person infected all the susceptible people. b. In the game model, the one infected person began to infect the susceptible people. However, the number of recovered people began to grow surprisingly fast (people were rolling a lot of 6’s). Eventually, almost everyone was recovered. c. For the full SIR model, we started with no recovered people, one infected person, and 999 susceptible people. The number of susceptible people took a huge dip as the infected number began to rise. The recovered value was also rising, only slightly slower than the infected value. Nearing the end of the model, it mirrored the game model in that the remaining people were mostly recovered. 2) a. The interaction rate is a constant that says how many interactions (possible opportunities for getting sick) there will be per delta time. b. The infection rate is a fraction or decimal that dictates what fraction of the people coming in contact with a sick person will actually get sick. c. The recovery rate tells what percentage of infected people will recover and become immune to the disease. 3) Trees in a forest fire a. The trees that are not yet on fire (the untouched part of the forest). b. The trees that are on fire and can spread the flames. c. The trees that have been doused with water or fire stopping chemicals and are out of danger of catching on fire again. d. The susceptible number of trees will be the greatest to begin with. The few infected (on fire) trees will start to infect (catch fire to) the other trees. Soon, the majority of the trees will be infected. Then, the forest fire department will put out the fire that is consuming a number of the infected trees. These trees are out of the way of the spreading fire and will no longer be able to catch on fire (recovered). Soon, all the trees will either be recovered or completely burnt by the fire.