30  Verifying and improving

There are many other points to refactor, explore alternatives and expand. Just remember to think it through first, then start writing code.

Do consider making any changes and improvements in the version that was already broken down into modules (“submodelled”): BlockC_module6_MesaraTrade_submodelled.nlogox.

Here are a few examples, in order of difficulty:

30.1 Basic challenges

  • Customise the shapes of turtles to something other than “circle 2” and “person”.
  • Visualise catchmentArea as the pixel size of settlements in the NetLogo View, instead of sizeLevel
  • Implement an effect of rivers in patchCost values. Feel free to experiment with both positive and negative effects.

30.2 Intermediate challenges

  • Extend the map so that the patches beyond the coastline explicitly represent the sea and make travelling by water an attractive option for traders. When considering potential solutions, remember the computational cost of recalculating land routes.
  • Modify the trade mechanism so that catchmentArea also serves as a proxy for political sphere and sizeLevel as political influence or power, having an additional effect on trade attractiveness. Does this addition to the model design affect the dynamics?

30.3 Advanced challenge

One tick in the weather data corresponds to one day, but most sites in the Messara region could be travelled within one or two days on foot. Therefore, the step-by-step movement of traders used in the Pond Trade model makes traders unrealistically slow in this setting. Find a way to calibrate the speed of traders to the same daily rhythm of the weather variables.

(Consider that there are many potential solutions to this problem. One solution is already present in BlockC_module6_MesaraTrade_submodelled_mod.nlogox.)

With your solution, or the one in the repository, run the model again with the default settings and observe whether and how the change affected the dynamics.