PERCENT ROOT MEAN SQUARED ERROR The percent root-mean-squared-error (RMSE) indicates whether the simulated network contains an acceptable level of assignment error. This is based on both the area-wide and volume group summaries. Accuracy is more stringent for higher volume facilities than for lower volume facilities. No RMSE category failed to meet established accuracy ranges with the Polk County 2007model.
The FSUTMS model update, Task C report, gives a number of validation criteria: Validation Check
Scale of Computation
Assigned VMT/Count VMT
Area
+/- 5%
Assigned VHT/Count VHT
Area
+/- 5%
Volume-Count Ratio
Screenlines
Facility Type, Area Type, No. of Lanes Facility Type, Area Type, Assigned VHT/Count VHT No. of Lanes
Assigned VMT/Count VMT
% Root Mean Square Error
Area
% Root Mean Square Error
Link Volume Groups
Level of Accuracy Vehicles per Day Level of Accuracy
+/- 20%
< 50K >
+/- 10%
+/- 20%
< 100K >
+/- 15%
+/- 15%
< 20K >
+/- 25% +/- 35%-50%
+/- 100%
< 50K >
+/- 25%
Source: FSUTMS model update, Task C
The highway model evaluation summary provides the following details of the model:
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