GTIS Travel Time Report #2
Statistics for Agency:IL-IDOTD8 Route:IL-159

   Year        Month
Year: 2021 Month: January
Direction Segment Start Segment End
Total Length (mi)
  • Total length of all segments for the route listed (may include overlapping segments)
Total Travel Time, GTIS (min)
  • Average total travel time for all segments as reported by the Gateway Traveler Information System (GTIS)
Total Travel Time, NPMRDS (min)
  • Average total travel time for all segments as reported by the National Performance Management Research Data Set (NPMRDS)
Similarity 1 (%)
  • Based on Normalized Root Mean Square Error (NRMSE)
  • Shows how similar the values are / error in measurements
Similarity 2 (%)
  • Based on Mean Absolute Percentage Error (MAPE)
  • Shows how similar the values are / error in measurements
  • Deviation between data points in terms of percentage, effected largely by overforecasts
Abnormality (%)
  • Based on data lying outside of three standard deviations from the mean versus what would normally be expected
  • Affected by GTIS and NPMRDS evenly
Association (%)
  • Based on correlation coefficient between datasets
  • Can you predict one value based on the other
Inequality (%)
  • Based on Theil statistics for the data
  • Suite of four statistics commonly used to compare travel time data
  • Measuring covariance, variance, and bias
Bias (%)
  • Based on Theil bias statistic only
Omission (%)
  • Based on data availability
  • Large amounts of unavailable data results in lower score
Overall (%)
  • Weighted average of the seven intermediate statistics
Change From Last Month(%)
  • Percent change in overall score from previous month
NBI-70I-2703.305.375.8062.0886.7892.5557.0842.4596.0573.0073.33N/A
NBI-64I-708.1112.5314.5363.2386.2891.6955.7339.3186.0183.5973.01N/A
NBOverall11.4017.9020.3462.6686.5392.1256.4140.8891.0378.3073.17N/A
SBI-270I-703.335.335.9276.6686.9087.3469.1649.7981.6573.3577.02N/A
SBI-70I-648.0912.7015.0467.4183.9185.7060.2742.2477.2680.8272.46N/A
SBOverall11.4218.0320.9672.0385.4186.5264.7246.0179.4577.0874.74N/A
Overall22.8335.9441.3067.3485.9789.3260.5643.4585.2477.6973.95N/A
Cells are highlighted red when they decrease by more than -5.03 percentage points which represents the 5th percentile of monthly changes at this aggregation from 2017-2024.
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