15  Implementing output statistics

Apart from minor refactoring, the last implementation steps involve displaying (step 12) and recording (step 13) output statistics. These are essentially aggregate measurements about the state of the simulation at a given time step.

Pond Trade step 12

Pond Trade step 13

The statistics serve as indicators for monitoring complex results while manually running simulations in the interface. Most importantly, they can be used more systematically as data that can be exported for further use in other software, e.g., to perform advanced statistical analyses and more sophisticated graphs.

Here is how step 13 implements those statistics:

globals
[
  routes

  ;;; Output
  patchesCount
  coastalLandPatchesCount

  traderCount

  meanTraderCargoValue
  minTraderCargoValue
  maxTraderCargoValue

  minSettlementSize
  maxSettlementSize
  mainHub

  meanTotalPathCostOfActiveRoutes
  minTotalPathCostOfActiveRoutes
  maxTotalPathCostOfActiveRoutes

  meanRedTrait stdDevRedTrait modesRedTrait
  meanGreenTrait stdDevGreenTrait modesGreenTrait
  meanBlueTrait stdDevBlueTrait modesBlueTrait

  meanLandTechTrait stdDevLandTechTrait modesLandTechTrait
  meanPortTechTrait stdDevPortTechTrait modesPortTechTrait

  meanSizeDecayTrait stdDevSizeDecayTrait modesSizeDecayTrait
  meanStockDecayTrait stdDevStockDecayTrait modesStockDecayTrait
  meanProductionTrait stdDevProductionTrait modesProductionTrait

  meanFreqOverQualTrait stdDevFreqOverQualTrait modesFreqOverQualTrait
  meanTransmissionTrait stdDevTransmissionTrait modesTransmissionTrait
  meanMutationTrait stdDevMutationTrait modesMutationTrait
]

...


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; OUTPUT ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

to update-output

  set coastalLandPatchesCount count patches with [isLand = true and any? neighbors with [isLand = false]]

  let activatedTraders traders with [isActivated]

  set traderCount count activatedTraders

  set meanTraderCargoValue mean [cargoValue] of activatedTraders
  set minTraderCargoValue min [cargoValue] of activatedTraders
  set maxTraderCargoValue max [cargoValue] of activatedTraders

  set minSettlementSize min [sizeLevel] of settlements
  set maxSettlementSize max [sizeLevel] of settlements
  set mainHub max-one-of settlements [sizeLevel]

  set meanTotalPathCostOfActiveRoutes mean [sum (map [ ?1 -> [pathCost] of ?1 ] route)] of activatedTraders
  set minTotalPathCostOfActiveRoutes min [sum (map [ ?1 -> [pathCost] of ?1 ] route)] of activatedTraders
  set maxTotalPathCostOfActiveRoutes max [sum (map [ ?1 -> [pathCost] of ?1 ] route)] of activatedTraders

  set meanRedTrait mean [item 0 culturalVector] of settlements
  set stdDevRedTrait standard-deviation [item 0 culturalVector] of settlements
  set modesRedTrait modes [ round (item 0 culturalVector) ] of settlements
  set meanGreenTrait mean [item 1 culturalVector] of settlements
  set stdDevGreenTrait standard-deviation [item 1 culturalVector] of settlements
  set modesGreenTrait modes [ round (item 1 culturalVector) ] of settlements
  set meanBlueTrait mean [item 2 culturalVector] of settlements
  set stdDevBlueTrait standard-deviation [item 2 culturalVector] of settlements
  set modesBlueTrait modes [ round (item 2 culturalVector) ] of settlements

  set meanLandTechTrait mean [item 3 culturalVector] of settlements
  set stdDevLandTechTrait standard-deviation [item 3 culturalVector] of settlements
  set modesLandTechTrait modes [ round (relativePathCostInLand + item 3 culturalVector) ] of settlements
  set meanPortTechTrait mean [item 4 culturalVector] of settlements
  set stdDevPortTechTrait standard-deviation [item 4 culturalVector] of settlements
  set modesPortTechTrait modes [ round (relativePathCostInPort + item 4 culturalVector) ] of settlements

  set meanSizeDecayTrait mean [item 5 culturalVector] of settlements
  set stdDevSizeDecayTrait standard-deviation [item 5 culturalVector] of settlements
  set modesSizeDecayTrait modes [ round (item 5 culturalVector) ] of settlements
  set meanStockDecayTrait mean [item 6 culturalVector] of settlements
  set stdDevStockDecayTrait standard-deviation [item 6 culturalVector] of settlements
  set modesStockDecayTrait modes [ round (item 6 culturalVector) ] of settlements
  set meanProductionTrait mean [item 7 culturalVector] of settlements
  set stdDevProductionTrait standard-deviation [item 7 culturalVector] of settlements
  set modesProductionTrait modes [ round (item 7 culturalVector) ] of settlements

  set meanFreqOverQualTrait mean [item 8 culturalVector] of settlements
  set stdDevFreqOverQualTrait standard-deviation [item 8 culturalVector] of settlements
  set modesFreqOverQualTrait modes [ round (item 8 culturalVector) ] of settlements
  set meanTransmissionTrait mean [item 9 culturalVector] of settlements
  set stdDevTransmissionTrait standard-deviation [item 9 culturalVector] of settlements
  set modesTransmissionTrait modes [ round (item 9 culturalVector) ] of settlements
  set meanMutationTrait mean [item 10 culturalVector] of settlements
  set stdDevMutationTrait standard-deviation [item 10 culturalVector] of settlements
  set modesMutationTrait modes [ round (item 10 culturalVector) ] of settlements

end

We could further implement a procedure to export these and more variables at a specific time of simulations. We will see an example of this in Block C. However, in most cases, we want to use NetLogo Behavioral Space. Find it in Tools > Behavior Space. This built-in tool allows you to configure experiments to be run in parallel, within a specific parameter space, and perform a series of commands before, during, or after a simulation run. It includes functionality for exporting simulation data as a CSV file (you will be prompt with a File Explorer window once you press “run” in an experiment).

As the final step in developing PondTrade, let us update our second-tier conceptual model, adding a more explicit representation of cultural vectors and their contents.

Pond Trade conceptual model at step 13 (second tier)