GTIS Travel Time Report #2
Statistics for Agency:IL-IDOTD8 Route:I-55

   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
NBIL-111I-255N/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/A
NBI-64IL-111N/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/A
NBMississippi RiverI-64N/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/A
NBI-255Keebler RdN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/A
NBI-255I-2709.458.558.8193.5296.4192.4358.7787.9478.37100.0089.23N/A
NBMississippi RiverIL-32.752.892.3777.3977.9082.1475.6565.246.11100.0071.74N/A
NBSt Clair AveI-2557.216.736.4894.3195.6465.4987.1681.9154.09100.0086.35N/A
NBI-270IL-413.8311.8511.4993.1795.9098.1456.7381.5678.02100.0088.71N/A
NBOverall33.2430.0229.1589.6091.4684.5569.5879.1654.15100.0084.01N/A
SBIL-111I-64N/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/A
SBKeebler RdI-255N/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/A
SBI-46Mississippi RiverN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/A
SBI-255IL-111N/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/A
SBI-270I-2559.458.428.6493.0096.93100.0055.0377.0986.83100.0089.38N/A
SBI-255St Clair Ave7.276.736.7696.5097.8482.2175.4193.0098.27100.0093.48N/A
SBIL-3Mississippi River2.572.812.5688.1489.7489.9273.4076.6136.01100.0082.07N/A
SBIL-4I-27013.8311.8411.4392.6495.7298.7863.1965.8877.06100.0087.58N/A
SBOverall33.1329.7929.3992.5795.0692.7366.7678.1474.54100.0088.12N/A
Overall66.3659.8158.5491.0893.2688.6468.1778.6564.35100.0086.07N/A
Cells are highlighted red when they decrease by more than -5.28 percentage points which represents the 5th percentile of monthly changes at this aggregation from 2017-2024.
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