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

   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
EBDixon PlazaDeKalb Plaza30.3527.6727.1892.3296.0395.0072.1696.2294.5699.6592.85N/A
EBDeKalb PlazaAurora Plaza31.2028.9227.3591.8193.2086.7182.4978.9350.5899.8386.11N/A
EBOverall61.5556.5954.5292.0694.6290.8577.3387.5872.5799.7489.48N/A
WBAurora PlazaDeKalb Plaza31.2029.0327.6191.1993.9846.2083.1779.5166.10100.0083.79N/A
WBDeKalb PlazaDixon Plaza30.3427.2427.1492.8195.6243.6376.9287.9199.7399.1387.84N/A
WBOverall61.5456.2754.7592.0094.8044.9180.0483.7182.9199.5785.82N/A
Overall123.09112.86109.2892.0394.7167.8878.6885.6577.7499.6587.65N/A
Cells are highlighted red when they decrease by more than -5.43 percentage points which represents the 5th percentile of monthly changes at this aggregation from 2017-2024.
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