1 National Household Travel Survey (NHTS) Add-on Status Model Task Force Data Committee October 17, 2008.

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National Household Travel Survey (NHTS) Add-on Status

Model Task Force Data CommitteeOctober 17, 2008

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Presentation Overview

Funding and NHTS Background

Sampling Plan

Current Status

Discussion

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Funding and NHTS Background

Funding approved by MPOAC via PL Funds

– Total cost for 12,000 urban samples is $2,100,000

– Data analysis & tabulation $500,000

– FDOT allocated $350,000 for 2,000 rural samples

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Funding and NHTS Background

Daily data collected includes:

– Purpose of the trip (work, shopping, etc.)

– Means of transportation used (car, bus, subway, walk, etc.)

– How long the trip took (i.e., travel time)

– Time of day when the trip took place

– Day of week when the trip took place

– Private vehicle trip details

number of people in the vehicle (i.e., vehicle occupancy)

driver characteristics (age, sex, worker status, education level, etc.)

vehicle attributes (make, model, model year, amount of miles driven in a year)

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Funding and NHTS Background

Data used to:

– Quantify travel behavior

– Analyze changes in travel characteristics over time

– Relate travel behavior to the demographics of the traveler

– Study the relationship of demographics and travel over time

Data items not included:

– Travel costs

– Information on specific routes

– Longitudinal information

– Reasons for specific mode

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Sampling Plan

Proposed Sampling Plan– Region 1 – Collier, Lee, Charlotte, Sarasota, and Manatee (Census 2000

Households: 545,158 )– Region 2 – Duval, St. Johns, Clay, Nassau, and Alachua (Census 2000

Households: 613,890 )– Region 3 – Leon, Gadsen, Wakulla, Walton, Okaloosa, Santa Rosa, Escambia,

and Bay (Census 2000 Households: 424,149 )– Region 4 – Broward, Miami-Dade, Palm Beach, Indian River, St. Lucie, and Martin

(Census 2000 Households: 2,150,666 )– Region 5 – Orange, Osceola, Seminole, Lake, Sumter, Brevard, Volusia, and

Marion (Census 2000 Households: 1,040,095 )– Region 7 – District 7 (except Citrus) and Polk (Census 2000 Households:

1,196,954 )– Region 8 – Rural counties not in the first six (Census 2000 Households: 370,209 )

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Sampling Plan

    Sample Size Confidence Interval (95% CL)

RegionNumber of Households Original Revised Original Revised

1 545,158 1,096 1,200 ± 3.0% ± 2.8%

2 613,890 1,234 1,234 ± 2.8% ± 2.8%

3 424,149 852 1,200 ± 3.4% ± 2.8%

4 2,150,666 4,322 4,116 ± 1.5% ± 1.5%

5 1,040,095 2,090 2,000 ± 2.1% ± 2.2%

7 1,196,954 2,406 2,250 ± 2.0% ± 2.1%

8 370,209 2,000 2,000 ± 2.2% ± 2.2%

Total 6,341,121 14,000 14,000 ± 0.8% ± 0.8%

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Sampling Plan

Region Sample Size

Region 1 1,200

Region 2 1,224

Region 3 1,200

Region 4 4,116

Region 5 2,000

Region 7 2,250

Region 8 2,000

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Sampling Plan

MPO Sample Size

Each MPO will be sampled such that atleast 80% of the sampled

households from the MPO are included in the region sample

Why do this?

– Makes data collection more cost effective

– Ensures sufficient samples for segmentation

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Sampling Plan

Rural Counties

FDOT District Total Households Sample SizeConfidence Interval (95% CL)

1 83,828 453 ± 4.6%

2 125,436 678 ± 3.8%

3 51,894 280 ± 5.9%

5 21,284 115 ± 9.2%

6 35,106 190 ± 7.1%

7 52,661 284 ± 5.8%

Rural Total 370,209 2,000 ± 2.2%

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Current Status

Very positive response rate

Slated to complete in April 2009

Region

Category Total FL

Total Target Sample Size 14,000 14,000

Useable Households (final) as of 10/14/2008 6,278 6,278

% of Completion Goal 44.8% 44.8%

Extended (Retrieval) HH Cooperation Rate (%) 74.1% 74.1%

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Current Status

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Per

cen

t C

om

ple

te

Region 1 Region 2 Region 3 Region 4 Region 5 Region 7 Region 8

Sampling Region

Statewide Completion

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0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Per

cen

t C

om

ple

te

Charlotte County-Punta Gorda MPO

Collier County MPO Lee County MPO Sarasota/ManateeMPO

North Florida TPO Gainesville MTPO

MPO

Region 1 and Region 2

Current Status

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Current Status

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Per

cen

t C

om

ple

te

Bay CountyTPO

CapitalRegion

TPA

Florida-Alabama

TPO

Okaloosa-Walton TPO

BrowardMPO

IndianRiver

CountyMPO

MartinCounty

MPO

Miami-Dade PalmBeachCounty

MPO

St. LucieTPO

MPO

Region 3 and Region 4

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Current Status

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Pe

rce

nt

Co

mp

lete

Brevard MPO Lake-SumterMPO

Ocala/MarionCounty TPO

METROPLANOrlando

Volusia CountyMPO

HernandoCounty MPO

HillsboroughCounty MPO

Pasco CountyMPO

Pinellas CountyMPO

Polk TPO

MPO

Region 5 and Region 7

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Current Status

10%

11%

12%

13%

14%

15%

Sunday Monday Tuesday Wednesday Thursday Friday Saturday

Travel Day of Week

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Discussion