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From page 122... ... 122 FIGURE 12-1 FLOW DIAGRAM OF THE ADAPTED FHWA LONG-DISTANCE MODEL SYSTEM The next step of the modeling process includes a long-distance tour-generation and scheduling model that predicts the number of long-distance tours (round trips) that a household makes during every month of the year for each of five different travel purposes (business, commuting, visit friends or relatives, vacation/leisure, and "other," which includes purposes such as medical, shopping, and college) Read the entire page →
From page 123... ... 123 Finally, based on the household characteristics and the characteristics of the tours, the model uses the precalculated mode/destination choice probabilities to predict the choice of a specific destination zone and mode used for each tour. (For each disaggregate choice, the model software draws a random number and uses it in "Monte Carlo" stochastic simulation -- analogous to spinning a roulette wheel -- where the number of slots allocated to each possible choice outcome is based on the model probabilities.) Read the entire page →
From page 124... ... 124 Northeast Corridor) , so any diversion to or from rail or bus would not substantially affect the results of the analysis. Read the entire page →
From page 125... ... 125 TABLE 12-1: 2011 NATIONAL CALIBRATION TARGETS DERIVED FROM FHWA TAF MATRICES DISTANCE BAND (MILES) TAF CAR TRIPS TAF AIR TRIPS TAF TOTAL TRIPS TAF AIR MODE SHARE 100–200 1,158,188,814 1,346,063 1,159,534,877 0.1% 200–400 823,967,452 43,234,928 867,202,381 5.0% 400–600 277,274,338 54,272,117 331,546,455 16.4% 600–800 136,737,303 57,228,023 193,965,327 29.5% 800–1000 68,371,100 54,479,400 122,850,500 44.3% 1000–1200 33,225,345 58,342,447 91,567,792 63.7% 1200–1400 17,313,278 43,227,409 60,540,687 71.4% 1400–1600 5,168,362 23,256,336 28,424,699 81.8% 1600–3200 15,645,891 109,542,450 125,188,341 87.5% Total 2,535,891,883 444,929,175 2,980,821,058 14.9% TABLE 12-2: TOTALS FROM THE ACRP MODEL AFTER CALIBRATION DISTANCE BAND (MILES) Read the entire page →
From page 126... ... 126 FIGURE 12-2: PLOT OF TAF VS. ACRP MODEL AIR AND CAR TRIPS AFTER CALIBRATION 200,000,000 400,000,000 600,000,000 800,000,000 1,000,000,000 1,200,000,000 TAF and ACRP Model Car and Air Trips, by Distance Band (miles) Read the entire page →
From page 127... ... 127 FIGURE 12-3: PLOT OF TAF VS. ACRP MODEL AIR MODE SHARES AFTER CALIBRATION The TAF data are not split by journey purpose, nor are the DB1B air ticket data. Read the entire page →
From page 128... ... 128 TABLE 12-3: ACRP MODEL AIR MODE SHARES, BY DISTANCE BAND AND TOUR PURPOSE DISTANCE BAND (MILES) PERSONAL BUSINESS VISIT FRIENDS/ RELATIVES LEISURE COMMUTING EMPLOYER'S BUSINESS TOTAL 100–200 0.1% 0.2% 0.2% 0.2% 0.3% 0.2% 200–400 3.3% 4.0% 5.1% 3.3% 11.3% 5.1% 400–600 13.5% 16.3% 17.6% 13.4% 36.8% 18.7% 600–800 26.4% 29.6% 30.7% 25.9% 54.1% 33.0% 800–1000 40.7% 43.6% 44.7% 42.3% 64.7% 46.7% 1000–1200 56.2% 60.2% 59.2% 58.8% 77.3% 61.5% 1200–1400 63.0% 67.2% 65.5% 63.2% 81.2% 68.1% 1400–1600 70.9% 74.9% 73.7% 69.6% 85.3% 75.7% 1600–3200 84.5% 88.4% 87.0% 84.4% 90.8% 87.9% Total 11.0% 16.6% 14.8% 3.2% 25.3% 15.4% FIGURE 12-4: PLOT OF ACRP MODEL AIR MODE SHARES, BY TOUR PURPOSE The research team performed further calibration and validation for airports serving specific markets. Read the entire page →
From page 129... ... 129 Houston, and Greensboro, North Carolina. Greensboro was chosen because it has a regional airport that is less than 100 miles from two larger airports in Charlotte and Raleigh-Durham. Read the entire page →
From page 130... ... 130 of calibration is not to match the targets exactly, but for the model to be predicting actual demand reasonably well to serve as a basis for the scenario sensitivity tests. Read the entire page →

From page 122...

... 122 FIGURE 12-1 FLOW DIAGRAM OF THE ADAPTED FHWA LONG-DISTANCE MODEL SYSTEM The next step of the modeling process includes a long-distance tour-generation and scheduling model that predicts the number of long-distance tours (round trips) that a household makes during every month of the year for each of five different travel purposes (business, commuting, visit friends or relatives, vacation/leisure, and "other," which includes purposes such as medical, shopping, and college)

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From page 123...

... 123 Finally, based on the household characteristics and the characteristics of the tours, the model uses the precalculated mode/destination choice probabilities to predict the choice of a specific destination zone and mode used for each tour. (For each disaggregate choice, the model software draws a random number and uses it in "Monte Carlo" stochastic simulation -- analogous to spinning a roulette wheel -- where the number of slots allocated to each possible choice outcome is based on the model probabilities.)

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From page 124...

... 124 Northeast Corridor) , so any diversion to or from rail or bus would not substantially affect the results of the analysis.

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From page 125...

... 125 TABLE 12-1: 2011 NATIONAL CALIBRATION TARGETS DERIVED FROM FHWA TAF MATRICES DISTANCE BAND (MILES) TAF CAR TRIPS TAF AIR TRIPS TAF TOTAL TRIPS TAF AIR MODE SHARE 100–200 1,158,188,814 1,346,063 1,159,534,877 0.1% 200–400 823,967,452 43,234,928 867,202,381 5.0% 400–600 277,274,338 54,272,117 331,546,455 16.4% 600–800 136,737,303 57,228,023 193,965,327 29.5% 800–1000 68,371,100 54,479,400 122,850,500 44.3% 1000–1200 33,225,345 58,342,447 91,567,792 63.7% 1200–1400 17,313,278 43,227,409 60,540,687 71.4% 1400–1600 5,168,362 23,256,336 28,424,699 81.8% 1600–3200 15,645,891 109,542,450 125,188,341 87.5% Total 2,535,891,883 444,929,175 2,980,821,058 14.9% TABLE 12-2: TOTALS FROM THE ACRP MODEL AFTER CALIBRATION DISTANCE BAND (MILES)

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From page 126...

... 126 FIGURE 12-2: PLOT OF TAF VS. ACRP MODEL AIR AND CAR TRIPS AFTER CALIBRATION 200,000,000 400,000,000 600,000,000 800,000,000 1,000,000,000 1,200,000,000 TAF and ACRP Model Car and Air Trips, by Distance Band (miles)

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From page 127...

... 127 FIGURE 12-3: PLOT OF TAF VS. ACRP MODEL AIR MODE SHARES AFTER CALIBRATION The TAF data are not split by journey purpose, nor are the DB1B air ticket data.

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From page 128...

... 128 TABLE 12-3: ACRP MODEL AIR MODE SHARES, BY DISTANCE BAND AND TOUR PURPOSE DISTANCE BAND (MILES) PERSONAL BUSINESS VISIT FRIENDS/ RELATIVES LEISURE COMMUTING EMPLOYER'S BUSINESS TOTAL 100–200 0.1% 0.2% 0.2% 0.2% 0.3% 0.2% 200–400 3.3% 4.0% 5.1% 3.3% 11.3% 5.1% 400–600 13.5% 16.3% 17.6% 13.4% 36.8% 18.7% 600–800 26.4% 29.6% 30.7% 25.9% 54.1% 33.0% 800–1000 40.7% 43.6% 44.7% 42.3% 64.7% 46.7% 1000–1200 56.2% 60.2% 59.2% 58.8% 77.3% 61.5% 1200–1400 63.0% 67.2% 65.5% 63.2% 81.2% 68.1% 1400–1600 70.9% 74.9% 73.7% 69.6% 85.3% 75.7% 1600–3200 84.5% 88.4% 87.0% 84.4% 90.8% 87.9% Total 11.0% 16.6% 14.8% 3.2% 25.3% 15.4% FIGURE 12-4: PLOT OF ACRP MODEL AIR MODE SHARES, BY TOUR PURPOSE The research team performed further calibration and validation for airports serving specific markets.

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From page 129...

... 129 Houston, and Greensboro, North Carolina. Greensboro was chosen because it has a regional airport that is less than 100 miles from two larger airports in Charlotte and Raleigh-Durham.

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From page 130...

... 130 of calibration is not to match the targets exactly, but for the model to be predicting actual demand reasonably well to serve as a basis for the scenario sensitivity tests.

Read the entire page →

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