GTIS Travel Time Report #2
Statistics for Agency:IL-TESTTIMS Route:I-88

   Year        Month
Year: 2023 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
EBDixon PlazaDeKalb Plaza30.3526.1326.2495.2597.8289.1480.9992.0599.28100.0094.410.72
EBDeKalb PlazaAurora Plaza31.2027.0626.3795.8996.7189.9284.8284.0458.96100.0089.932.76
EBOverall61.5553.2052.6195.5797.2789.5382.9088.0479.12100.0092.171.23
WBAurora PlazaDeKalb Plaza31.2027.3726.4995.2196.0494.2881.9876.1852.29100.0088.284.02
WBDeKalb PlazaDixon Plaza30.3426.2226.2996.3798.0077.7185.7698.4099.48100.0094.73-2.59
WBOverall61.5453.5852.7895.7997.0286.0083.8787.2975.88100.0091.511.23
Overall123.09106.78105.3895.6897.1487.7683.3987.6777.50100.0091.841.23
Cells are highlighted red when they decrease by more than -5.56 percentage points which represents the 5th percentile of monthly changes at this aggregation from 2017-2025.
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