Topic 107

Key terms —model, simulation, feedback loop by Xiao Xiao Li

Model – A model is basically a representation of something big. Maps are example of models. Dictionary defines a model as “a simplified description, esp. a mathematical one, of a system or process, to assist calculations and predictions.” In this case, they are defining models in mathematics but that’s not the only place where models are used. Models are used everywhere today. In real life – the biggest example is a map and small subway maps and statutes etc. In subjects, economics – the circular flow diagram and in biology diagrams of the human body! All over the place!

Simulation – Dictionary defines it as “producing a computer model of something” and that’s pretty much what it is. A simulation is basically a simplication of reality. Simulation is used in many contexts, including the modeling of natural systems or human systems in order to gain insight into their functioning. Other contexts include simulation of technology for performance optimization, safety engineering, testing, training and education. Simulation can be used to show the eventual real effects of alternative conditions and courses of action. Simulation is often used in education. For example, the other day Mr. Sirkka used computer 3-D modeling in order to explain how two chemicals bond to each other and what angles they form! Simulation is often used in war scenarios too. For example, scientists test how a bomb will affect the city and the people living in it through computers and simulation!

Feedback loop – This is pretty hard to explain but I’ll try my best. According to the dictionary, “A feedback loop is a system where outputs are fed back into the system as inputs.” Basically, feedback loop doesn't really mean anything by itself. It is usually used in order to explain other things. For example, it is used to explain the cycle of poverty. Cycle of poverty means that the poor will always remain poor and this is explained by the “negative feedback loop”. Basically this means that since the poor people don’t have the resources to save and invest, they’ll never get a start on the economic development process. This is the feedback loop – you can’t put in the resources and thus won’t get any output so that’s why there’s a “negative feedback loop.” A positive feedback loop would be where people are earning a lot of money and saving that money in their banks and thus “outputs are feedback into the system as inputs!”