NetLogo User Community Models

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Download If clicking does not initiate a download, try right clicking or control clicking and choosing "Save" or "Download".(The run link is disabled for this model because it was made in a version prior to NetLogo 6.0, which NetLogo Web requires.)

WHAT IS IT?

This is a model of language evolution, where agents are human populations that possess a dialect. A dialect is modelled here as simply an ordered array of ones and zeros.

HOW IT WORKS

Two dialects are considered variants of the same language if they are mutually intelligible. Otherwise they are different languages.

HOW TO USE IT

Mutation rate is how fast dialects change on their own. Borrow rate is how fast they are influenced by neighbouring, mutually intelligible dialects. Mutual intelligibility ratio is how similar two dialects must be for one to say they can understand the other.

THINGS TO NOTICE

If two agents have the same dialect, they will be the same colour. However, two agents with the same colour may or may not have the same dialect.
Calculating language diversity is somewhat intense computationally and causes the program to stall momentarily. For this reason a switch and slider are provided to allow you to plot this value less often or not at all.

THINGS TO TRY

Try drawing boundaries by clicking on that button and then clicking and dragging on the world. You can draw them first and then populate the world, or populate first and then draw accordingly.

EXTENDING THE MODEL

Each agent could take its mutation rate as a random multiple of the global parameter; the dialect could be modelled with numbers between 0 and some number much higher than 1; the dialect could have sub-arrays to account for the faster- and slower-changing parts of itself, and these could also be weighted when determining the mutual intelligibility; and so on...

NETLOGO FEATURES

This model provided some good exercise in working with lists, the NetLogo equivalent of arrays.

RELATED MODELS

Genetic Drift - "GenDrift T interact" is similar in many respects

CREDITS AND REFERENCES

Made by Chuck Cranston for a class taught by Dr Jeff Fletcher at Portland State University, fall 2009.