NETLOGO BEHAVIOR SPACE INSTALL
NETLOGO BEHAVIOR SPACE SOFTWARE

In this experiment residents evaluate 30 locations. In Experiment 1, residents selected the best location from a list of 10 locations. Our second experiment investigates the effects of increasing the amount of information ('numtests') of each resident. What mechanisms in the model act as centripetal forces (cause increasing clustering) and which ones act as centrifugal forces (cause more sprawl)? The openABM initiative has a useful Behavior Space tutorial that may be of interest.

NETLOGO BEHAVIOR SPACE INSTALL

If you are feeling keen and want to try to set up Behavior Space for your experiments then you will have to download and install NetLogo on your computer, export the code for the SOME model from the SOME model page, and under the Tools menu item you can find the BehaviorSpace tool. It would be even better if you could have the model iterate a number of times for each of several parameter settings! NetLogo has a tool to do this, which is called Behavior Space.

NETLOGO BEHAVIOR SPACE SOFTWARE

It would be more efficient if you were able to run the model multiple times using the same parameter settings and have the software automatically record the results of those individual runs for you. It is easy enough to run and watch the model 20 times for each experiment because it is a simple model. Discuss when you should report the average and standard deviation of model outputs and how this information might be used to determine how many times you should run a model with the same set of parameters. Compute the average and standard deviation. Run the model 20 times and record the number of settlements beyond the sprawl boundary. What is required to make a model stochastic or deterministic and how could we modify the SOME model to be one or the other? Does each run produce the same number of settlements beyond the urban growth boundary? Discuss why the number of settlements beyond the boundary do not change (or do change) each time the model is run. Describe the behavior of the model and why you observe the produced settlement patterns for one or two typical model runs? You can calculate the average and standard deviation for each model setting if you like for comparison with the other experiments. This will allow you to compare model settings for the degree of sprawl they produce. You can read the numbers off the graph by pointing your mouse at the appropriate location on the graph. Run the model at least five times and measure the amount of sprawl by recording the number of developments outside the radius at the end of the model run. Run the model a couple times by repeating the procedure listed above to get a feel for how the SOME model works and how the process represented in the model produces the final outcomes you observe. If it seems like the model is running too fast to watch you can either run through the model one step at a time using the NEXT STEP button or you can move the 'speed' slider at the top of the NetLogo model. When you are ready you can press the GO button and the model will run. Since there are several parameters that can be changed, you may want to create a worksheet in Excel and record the different parameter values and model results as you run the model multiple times and you may want to compare among model runs or between experiments. The sample size limitation reflects the imperfect or incomplete information that residents have when they choose a residence. In fact, they consider only ten random locations, which in a landscape of 6400 locations represents a sample size of less than 1%.

In this experiment, the residential household agents do not look at many locations before choosing a place to live. The landscape should be initialized with aesthetic quality values, a sprawl boundary, a smooth landscape, luab off, and a sampling of ten locations (i.e., numTests) for each residential household agent. SMOOTH LANDSCAPE, LOW INFORMATION button and then the SETUP button.

Once the new webpage opens click on the Exp#1. Go to the SOME model or click on an existing browser tab where you have the model open. The sprawl boundary has been set at a 25 cell radius from the initial service center, located at the center of the landscape. Our first experiment considers an environment in which there is no heterogeneity in the aesthetic quality of the land.

Netlogo behavior space