GTIS Travel Time Report #2
Statistics for Agency:IL-IDOTD8 Route:I-255

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
NB	I-64	I-55	4.58	4.24	4.29	85.78	95.71	96.86	61.17	75.90	99.19	100.00	88.69	N/A
NB	I-55	I-270	6.15	5.46	5.45	94.33	96.67	90.50	60.01	89.50	99.84	100.00	91.73	N/A
NB	Mississippi River	I-64	16.32	15.03	15.08	94.89	97.06	84.14	62.15	87.00	99.47	100.00	91.26	N/A
NB	Mississippi River	IL-3N	6.20	5.59	5.61	96.31	97.66	87.92	65.91	98.24	98.73	100.00	93.57	N/A
NB	IL-3N	I-64	10.10	9.44	9.49	92.31	95.91	88.00	56.41	91.03	99.49	100.00	90.55	N/A
NB	Overall		43.36	39.75	39.92	92.72	96.60	89.48	61.13	88.33	99.35	100.00	91.16	N/A
SB	I-270	I-55	6.15	5.51	5.56	94.50	97.11	96.26	57.45	84.46	96.36	99.74	91.33	N/A
SB	I-55	I-270	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
SB	I-55	I-64	4.56	4.76	4.40	72.39	86.71	94.35	50.85	82.78	91.08	100.00	81.68	N/A
SB	I-64	Mississippi River	16.20	15.23	14.87	95.09	96.87	88.57	63.25	86.36	76.55	100.00	89.46	N/A
SB	IL-3N	Mississippi River	6.20	5.88	5.55	93.05	93.68	92.35	66.06	72.49	26.63	100.00	82.43	N/A
SB	I-64	IL-3N	9.99	9.34	9.32	93.89	97.02	86.64	60.03	85.55	99.89	100.00	90.94	N/A
SB	Overall		43.10	40.72	39.71	89.78	94.28	91.64	59.53	82.33	78.10	99.95	87.17	N/A
Overall			86.46	80.47	79.63	91.25	95.44	90.56	60.33	85.33	88.72	99.97	89.17	N/A

Cells are highlighted red when they decrease by more than -4.4 percentage points which represents the 5th percentile of monthly changes at this aggregation from 2017-2024.
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