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From page 94... ... 94 C h A P T e r 2 Model System Calibration and Validation Process Because the Jacksonville DaySim implementation was "transferred" from Sacramento -- and the model coefficients and alternative-specific constants were initially estimated and calibrated for the Sacramento region -- the project team had to recalibrate the core model components to reflect Jacksonville region-specific travel patterns. Calibration and validation of the entire model system is a highly iterative process that involves making changes to individual model components to better match observed data sources, as well as evaluating the impacts of these changes on other model components and on overall model system performance. Read the entire page →
From page 95... ... 95 travel made jointly by members of the household. To address these missing persons, the person weights had to be adjusted to match regional controls of persons by person type developed to support creation of the synthetic population. Read the entire page →
From page 96... ... 96 data derived from NHTS show a fair amount of variation. Finally, Table 2.3 summarizes commute flows from the 2005–2009 ACS data. Read the entire page →
From page 97... ... 97 Day Pattern The day-pattern model predicts the number and purpose of tours and intermediate stops made by each individual. These predictions arise from a series of sequential submodels that address different aspects of each individual's daily activity pattern. Read the entire page →
From page 98... ... 98 observed tours by destination purpose. This table illustrates that, overall, DaySim is matching regional tours relatively well, with 4% too many tours across all purposes. Read the entire page →
From page 99... ... 99 Source: DaySim and NHTS. 0% 5% 10% 15% 20% 1 11 21 31 41 51 61 NHTS DaySim Figure 2.4. Read the entire page →
From page 100... ... 100 0% 5% 10% 15% 20% 1 11 21 31 41 51 61 NHTS DaySim Source: DaySim and NHTS. Figure 2.7. Read the entire page →
From page 101... ... 101 Table 2.11. Estimated Trip-Mode Shares, by Destination Purpose (%) Read the entire page →
From page 102... ... 102 Tour and Trip Time of Day One of the most compelling features of ABM approaches is that they have the capability to treat time explicitly and consistently across all travel choice dimensions. Rather than using fixed factors or broad time periods, activity-based models can consider detailed time periods, as well as desired arrival times, departure times, and activity durations. Read the entire page →
From page 103... ... 103 0.0% 5.0% 10.0% 15.0% 20.0% 25.0% 30.0% Be fo re 3: 30 4: 30 5: 30 6: 30 7: 30 8: 30 9: 30 10 :3 0 11 :3 0 12 :3 0 13 :3 0 14 :3 0 15 :3 0 16 :3 0 17 :3 0 18 :3 0 19 :3 0 20 :3 0 21 :3 0 22 :3 0 23 :3 0 0: 30 1: 30 2: 30 Af te r… NHTS DaySim Source: DaySim and NHTS. Figure 2.9. Read the entire page →
From page 104... ... 104 0.0% 2.0% 4.0% 6.0% 8.0% 10.0% 12.0% 14.0% 16.0% 18.0% 20.0% Be fo re 3: 30 4: 30 5: 30 6: 30 7: 30 8: 30 9: 30 10 :3 0 11 :3 0 12 :3 0 13 :3 0 14 :3 0 15 :3 0 16 :3 0 17 :3 0 18 :3 0 19 :3 0 20 :3 0 21 :3 0 22 :3 0 23 :3 0 0: 30 1: 30 2: 30 Af te r… NHTS DaySim Source: DaySim and NHTS. Figure 2.11. Read the entire page →
From page 105... ... 105 0.0% 5.0% 10.0% 15.0% 20.0% 25.0% 30.0% 35.0% 0: 00 1: 00 2: 00 3: 00 4: 00 5: 00 6: 00 7: 00 8: 00 9: 00 10 :0 0 11 :0 0 12 :0 0 13 :0 0 14 :0 0 15 :0 0 16 :0 0 17 :0 0 18 :0 0 19 :0 0 20 :0 0 21 :0 0 22 :0 0 23 :0 0 > 24 … NHTS DaySim Source: DaySim and NHTS. Figure 2.13. Read the entire page →
From page 106... ... 106 Observed Data Sources The following three sources of 15-min count and data were compiled from the Florida Department of Transportation (FDOT) Read the entire page →
From page 107... ... 107 Figure 2.16. Locations of PTMS and ITS data shown on the PLANNING network. Read the entire page →
From page 108... ... 108 Table 2.14. Daily Validation, by Facility Type Facility Type # Obs. Read the entire page →
From page 109... ... 109 Table 2.17. Midday Validation, by Facility Type Facility Type # Obs. Read the entire page →
From page 110... ... 110 200,000 400,000 600,000 800,000 1,000,000 1,200,000 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 DAYHOUR EST OBS Figure 2.17. Estimated and observed total volumes, by hour. Read the entire page →

From page 94...

... 94 C h A P T e r 2 Model System Calibration and Validation Process Because the Jacksonville DaySim implementation was "transferred" from Sacramento -- and the model coefficients and alternative-specific constants were initially estimated and calibrated for the Sacramento region -- the project team had to recalibrate the core model components to reflect Jacksonville region-specific travel patterns. Calibration and validation of the entire model system is a highly iterative process that involves making changes to individual model components to better match observed data sources, as well as evaluating the impacts of these changes on other model components and on overall model system performance.