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5 Short-term-memory-voters

by Michael Kuyumcu (Submitted: 04/19/2004)

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Have you ever been so disappointed by a politician of your favorite party that you switched your political opinion and elected another partie's candidate? Have you ever talked with a friend or a neighbor and after the talk adopted her or his general political opinion - or so much of it that you voted differently? Just for how long do you remember political facts? One day? One month? One year? Even longer? Congratulations to your long-term memory!

Anyhow, the average German voter remembers important political facts and governmental decisions for about 3 months. If she or he is politically interested, make it six months. Hardly ever any longer. Let's think this idea a little bit further. What would happen if a voter changed her or his opinion almost instantly - say, from day to day. Imagine, each and every voter goes for a talk to one of her or his 4 neighbors and after the talk adopts their political opinion - every day. Could you predict the outcome of such a mass behavior? What could be an emergent system behavior of such a short-term-memory population?

This idea, together with a sketch of how to program it, was first presented by Martin Gardner in one of the issues Scientific American. I just have forgotten when that was... But you see, this exactly is the issue.


Use the party slider to determine how many political parties there should be. It's not telling you how many guests to invite to your next celebration.

The choice selector beneath lets you pick one of two alternatives for the initial voters distribution, either each party has equal market shares, or you define a space-delimited list of percentages (integer or real numbers) for each party, for instance, you select four parties and enter their percentages (market shares) as "10 20 50 20". That would mean that party 1 is voted for by 10 % of the population, party 2 by 20 %, and so on.

After these choices click on the "Setup" button. The colors on the patches now represent political opinions. There are as many colors as there are political opinions. Then click on »Start Simulation«. The voters living on the patches will begin adopting the political opinion of one of their four direct neighbors. The result of such an daily exchange is then displayed as a series of new patch images.


Give the model a little time, especially if you have a large number of patches and parties. Over time, notice what happens to the initial random distribution of opinions. And please bear with me - this is my first NetLogo model.


- Let the voters on the patches have an individual memory time. Some change opinions quickly, some need more or more frequent exposure to different ideas to change their mind. Sometimes, you just have to hammer home your point with one of your colleagues, haven’t you?
- New parties could be set up by discontented individuals or groups of people. Introduce a control that tells the simulation how often to introduce new political parties into the system and how many people minimum and maximum will have that initial opinion. How many blocks of voters should the new opinion be split upon? Will they live side by side or spread across the whole patch area?

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