Statistical Output

Output data files generated by SLEUTH are dependent upon the mode of the application. Further, function and flag settings in the scenario file act as secondary controls. Some contain information on memory storage and system performance while others store model output data. Generating log files can slow the model's performance considerably, especially during calibration. For general applications, most log flags should be set to "NO". The table below lists all statistic files generated by SLEUTH.

file name created in mode flag dependent
LOG_# T, C, P yes
avg.log T, C, P yes
coeff.log T, C, P yes
control_stats.log T, C no T, C, P no
std_dev.log T, C, P yes


T = test mode; C = Calibrate mode; P = predict mode; <> = static identifier; {} = variable identifier;

avg.log and std_dev.log
Measurements of simulated data, such as number of urban edges, clusters and urban pixels, are saved in the avg.log file. If in test or calibrate mode, for every year that real data exists (a control year) SLEUTH writes out a grid of urban extent (and land cover). Values are calculated from these grids and at the end of a run (a run begins with a single set of coefficient values and is executed n MONTE_CARLO_ITERATIONS). These values for each year are then averaged over the number of monte carlo iterations, and the result is written to the corresponding run number in control_stats.log. The standard deviations of the averaged values are written to the std_dev.log file. If in test mode, this process is performed for every year, not just the control years. The avg.log file may be used in the final step of calibration to derive forecasting coefficients.

Control_stats.log is generated in test or calibrate mode. It contains the r2 values of the simulated data (found in the avg.log file) compared to input urban (and land cover) data. The values for the input urban statistics can be written to the LOG_# file by setting the LOG_BASE_STATISTICS flag in the scenario file to "YES". This is the primary file used to narrow coefficient ranges during calibration.

Due to SLEUTH's self-modification qualities, coefficient values may be modified slightly after each growth cycle. The coeff.log file stores coefficient values for every run, monte carlo iteration and year. These data can also be written to the avg.log file. This file may be used in the final step of calibration to derive forecasting coefficients.


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