Transcript Document

DATA R US
Personal Travel Data,
including CTPP and NPTS
Portland State University
April 29, 2005
Elaine Murakami, FHWA
[email protected]
Ed Christopher, FHWA
[email protected]
What are Personal Travel
Data?
What are Personal Travel
Data?
l Daily activities and travel
l How we get to work
l When do we use the bus or rail
or air
l What are motivations for
traveling
l What are cost trade-offs (value
pricing)
Examples using Census and
CTPP data
Mode to Work, 1970 - 2000
Percent of Workers
U.S. Total
80
70
60
Drove Alone
Carpool
Transit
Walk
50
40
30
20
10
0
1980
1990
2000
Households without Vehicles
Percent, by Race/Hisp Origin
50
45
40
35
30
25
20
15
10
5
0
Total
Black
Hispanic
1970
1980
1990
2000
Travel Time to Work, 1990 and 2000
Percent of Workers
49 largest MSA’s
16
14
12
10
8
6
4
2
0
at
m
ho
e
< 5 5 to 9 to 14 15-19 20-24 25-29 30-34 35-39 40-44 45-59 60-89
10
2000
1990
0
>9
Examples using NPTS data
There were significantly more households in
2001 than in 1995 who owned a greater number
of vehicles than there were drivers in the
household
1995
2001
15 million
14.5 million
63 million
64.5 million
14 million
20 million
1.4 million
2.8 million
The average amount of time we spent in a vehicle in 2001
was slightly more than an hour. Children younger than 5
years old spent an average of ¾ of an hour a day in vehicles
65+
55-64
Age
45-54
35-44
25-34
19-24
6-18
0-5
10
20
30
40
50
60
70
Time Spent in Vehicles (minutes)
80
90
Average Daily Occupancy by Urbanized
Areas population and Trip Purpose
50,000199,999
200,000499,999
500,000999,999
1+ million
HBW
1.11
HBshop
1.44
HBSoc
1.66
HBNHB
Other
1.67
1.66
1.12
1.48
1.72
1.65
1.68
1.13
1.45
1.66
1.65
1.66
1.11
1.48
1.69
1.66
1.64
Source: NCHRP 365, using 1990 NPTS
Personal Travel:
Main data types
l
l
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Residence-based: households,
persons, vehicles, person trips
Workplace-based: employment/jobs,
workers, work trips
Other: Transit surveys: on-board,
rider/non-rider
Special attractors: airports,
schools/universities, major shopping
centers, etc.
Potential types of Questions
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Revealed preference – current
behavior
Stated preference – how might act in
future under certain conditions
Motivations for travel, and
scheduling changes
Residence-based
Household Travel Surveys
-- National
-- Regional/local
l
Decennial Census and American
Community Survey
l
Workplace-based

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l
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Public Sources
ES-202 files
Commercial Files
Dunn & Bradstreet
InfoUSA
CTPP Parts 2 and 3
LED program (test)
Today, focus on 2 main surveys
l
CTPP
-- Historical Trends
-- Small area data
-- Residence, Workplace AND Flow
l
NHTS
-- Historical Trends
-- Limited to Large geography only
-- Includes all trip purposes, trip
chaining file available
--NCHRP 365
--Data transferability project
What is the CTPP?
The Census Transportation
Planning Package is a set of special
tabulations from the long form of
the decennial census designed by
transportation planners for
transportation planners
It summarizes the data
Flows between
Home and Work
At Workplace
At Residence
Decennial Census Long Form
Sample is 1:6 addresses
nationwide, allowing for
reporting at very small
geography
Transportation Related Questions
-- Place of Work
-- Means of Transportation to Work
-- Carpool Occupancy to Work
-- Departure Time for Work
-- Travel Time to Work
-- Vehicles Available
What are the CTPP
Products?
Main CTPP Products
Tabulations
at Residence
Tabulations
at Workplace
Part 1
Part 2
Flows between
Home and Work
Collateral Products
 State and County Profiles
 County Flow Data
Part 3
How are they packaged?
CTPP Access Tool
The CAT
ASCII Too
CTPP Access Tool
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Easy to Use Software Interface
-- Easy to manipulate rows and
columns, including calculating new
variables
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.ivt files (proprietary format)
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Shape files included for many Census
geographic units
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Exports to .shp, .dbf, .xls, ASCII
l
Mapping and charting components
imbedded
What is in the CTPP?
Let’s Look at the Details
So how does this thing work?
Tables—Lots of Tables
121 Tables of Residents’ Based Data
68 Tables of Work Place Data
14 Tables of Flow Data
Variables--Lots of Variables
Person
Worker Status
Age, Sex, Race, Hispanic
Origin, Disability
Household
Income
Nos. Vehicles Available
Size and Nos. Workers
Workers
Journey-to-Work
Work Location and Mode
Departure and Travel Time
Arrival Time (Calculated)
Sample Table List
Data Issues
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Rounding
Thresholds
Workers at Work vs. Jobs or
Employment
Disclosure Review Board
CTPP 2000 Post DRB
Part 1: at Residence (121 Tables)
All Tables Rounded
Zero = 0
1 through 7 = 4
8 though  = Nearest Multiple of “5”
Part 2: at Workplace (68 Tables)
All Tables Rounded
Part 3: Worker Flows (14 Tables)
All Tables Rounded
Some Tables with Thresholds
Chicago CBD -CTPP 2000 Data
L11423
L11428
L11446
L11448
L11449
L12427
L12428
L12446
L12449
Rest
Total
SOV Carpool Bus
49,275 12,200
3,915 6,410
29,365 8,315
2,340 4,210
15,035 3,705
1,240 2,430
5,200 3,115
550
570
25,655 7,240
2,120 2,775
920
410
155
65
9,610 3,025
835 1,660
22,115 4,925
1,770 4,595
67,795 14,565
4,820 8,035
124,955 34,255 10,324 17,410
Col Tot 349,925 91,755
Rail
Other Home
24,580 2,160
10
12,780 1,715
4
7,010
640
15
745
150
65
12,325 1,195
0
85
95 105
3,535
555
0
9,915
905
0
36,950 3,420
0
57,165 5,460 328
28,069 48,160 165,090 16,295
527
Row Tot
49,275
29,364
15,040
5,195
25,655
915
9,610
22,110
67,790
124,942
349,896
Mode to Work for Travis County Residents
Tract
1.01
1.02
2.01
2.03
2.04
3.01
3.02
3.03
24.18
24.19
24.2
24.21
24.22
24.23
24.24
Total
SF3
CTPP
Car, truck, van
SF3
CTPP
Drove alone
SF3
CTPP
2,021
2020
1,850
1845
1,697
1695
1,231
1230
1,099
1094
1,062
1060
3,614
3615
2,899
2905
2,573
2575
243
245
191
190
129
130
2,036
2035
1,605
1605
1,485
1485
4,084
4085
3,065
3065
2,686
2685
3,342
3340
2,352
2350
2,194
2195
1,766
1765
1,373
1370
1,074
1075
2,296
2295
2,134
2135
1,758
1760
2,207
2205
2,072
2070
1,831
1830
4,088
4090
3,747
3750
2,955
2955
2,246
2245
2,133
2130
1,786
1785
3,045
3045
2,725
2725
2,122
2120
3,116
3115
2,925
2930
2,489
2490
1,889
1890
1,757
1754
1,416
1415
433,064 433,080 383,508 383,409 324,475 324,430
0.004%
-0.026%
-0.014%
Part 3: Worker Flow Tables
Table
Content
1
Total Workers (1)
2
Vehicles Available (3--zero,one or two+) by Means of Transportation (7 modes)
3
Poverty Status (3 categories)
4
Minority Status (2--white non-hispanic and all others)
5
Household Income (8 classifications)
6
Means of Transportation (17 modes)
7
Household Income (4 classifications) by Means of Transportation (4 modes)
8
9
No record
threshold
Must have 3
unweighted
records
Mean Travel Time by Means of Transportation to Work (7 modes) and Time
Leaving Home for Work (2--AM peak and all other times)
Median Travel Time by Means of Transportation to Work (7 modes) and Time
Leaving Home for Work (2 groupings)
10
Aggregate Number of Vehicles by Time Leaving Home for Work (2, see table 8)
11
Number of Workers per Vehicle by Time Leaving Home for Work (2, see table 8)
12
Aggregate Number of Carpools by Time Leaving Home for Work (2, see table 8)
13
Number of Workers per Carpool by Time Leaving Home for Work (2, see table 8)
14
Aggregate Travel Time by Means of transportation to work (7 modes) and Time
Leaving Home for Work (2, see table 8)
Impact of Thresholds on Workers
Included in Part 3 Tabulations
Intra-Bay Area, CTPP 2000, Part 3 Analysis
Table 3-1
No Threshold
Table 3-6
w/ Thresholds
County-to-County
3,258,465
Loss
3,258,465
Loss
Place-to-Place
3,257,152
0.0%
3,221,359
-1.1%
Tract-to-Tract
3,209,952
-1.5%
2,154,754 -33.9%
Zone-to-Zone
3,143,432
-3.5%
937,749 -71.2%
Special Thanks to Chuck Purvis, MTC
For this Analysis
Workers at Work Counts vs.
Other Employment Sources
Total jobs are HIGHER than CTPP
worker counts
CTPP uses NAICS, others may use SIC
Multi-site businesses and job types not reported
consistently
Census 2000 employment estimates vs CPS
Extended Allocation for CTPP small areas
http://www.trbcensus.com/articles/ctppworkers.pdf
With all this said and done
now what can I do?
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Build profiles (Part 1 example)
Trend Analysis
Survey Weighting
Planning Process
-- Environmental Justice, Title VI
-- TDM programs
-- Transit service planning
-- Model calibration and validation
Where do I get the “FREE” CTPP with
the CAT Software?
https://www.bts.gov/pdc/
Other Census Data
100% data or SHORT-FORM information
•
•
•
Redistricting Summary File (PL Data)
Summary File 1 (SF1)
Summary File 2
Sample data or LONG-FORM information
•
•
Summary File 3 (SF3)
Summary File 4
Public Use Microdata Sample Files (PUMS)
NHTS Basics
28,000 households in U.S. plus
nearly 44,000 households in add-on
Program.
lTelephone recruit, mail-out diary,
telephone retrieval.
l Cash incentives (recruit and diary)
l 41 percent overall response rate.
l March 2001 thru May 2002
l
NHTS Basics, continued
• Destination locations are only
geocoded for add-on records.
Otherwise, self-report for distance
• Sample size is small, relative to total
U.S. population, so geographic detail
is very limited, e.g. MSA size, some
states.
What travel is
included?
• Assigned travel for 1 day, includes all
365 days of the year. Good resource
for WEEKEND data, as 30 percent of
sample is for weekends!
• Long distance trips from 4-week
period.
• All modes of travel
What travel is
included?
The complexity of daily travel
360010129.00
360010130.00
360010135.03
Trip 5: Store to Store
360010138.02
360010135 .02
360010135.06
Trip 6: Store to Home
Trip 4: Work to Store
360010138.01
HOME
360010137.03
WORK
Trip 7: Home
to Day Camp
Trip 1: To Work
Trip 2: Work to Childs Day Camp
Trip 4: Store to Work
360010139.02
360010137.07
36 0010136.01
Trip 3: Day Camp to Store 360010139.01
360010004.01
360010146.07
360010140.01
360010137.05
360010137.06
360010140.02
36 00 10 00 4.04
360010146.10
360010136.02
360010146 .08
360010003.00
36 00 10 14 6.09
36 00 10 004.03
360010018.02
360010007.00
360010002.00 36 00 10 00 1.00
NHTS File structure
Land Use
Characteristics
(Claritas)
Households
Person 1
Veh 1
Vehicle Operating Char.
(EIA)
Veh 2
Person 2
Person 3
Trip 1
Trip 2
Trip 3
Trip 1
Trip 4
Trip 2
2001 NHTS Data Elements
Household demographics (race, age, sex,
household income)
Vehicle information (age, annual miles, fuel type
and use, etc.)
Commute information (mode, occupancy, time of
departure, work location and occupation, distance to
work)
Time of day and purpose for non-work Travel
(mode, occupancy, time, miles traveled)
Who’s traveling together from same household
2001 NHTS
Transferability Project
Test with 1995 NPTS data CITE for
transferability paper! ADD!!!!
Assist areas without recent hhld survey data
Trip Generation Rates and VMT accounting for
census-tract-level characteristics
Trips by Purpose, maybe be mode, and time of
day
2001 NHTS
Transferability Project
Use 2001 NHTS households (we have both
detailed travel, and census tract characteristics)
Develop clustering system, and cluster all
61,000+ census tracts, except Manhattan and
tracts without population.
Clustering system for 1995 had 11 clusters.
Compare the results of the “synthetic” hhlds to
the “real” households from the NHTS add-ons. If
this works, then….
2001 NHTS
Transferability Project
User defines their “study area” by selecting census
tracts.
Software returns Trip Generation Rates and VMT
by census tract, and study area totals.
1995 NPTS
Transferability Test:
11 clusters
Very High Inc.
Rural
Sub
Urban
3
High income
Mid. Income
Low income
9.6
19.8
11.1
High income
Mid. Income
Low income
11.1
16.6
8.7
High income
Mid. income
Low income
4.4
7.7
5.2
Very Low Income
2.8
0
5
10
15
% Census tracts
20
25
NPTS-based
Person Trips Per Household
1995 NPTS Transferability Test
Household
Size
Rural
Urban
Low
Income
Mid
Income
High
Income
1
3.6
4.0
2
8.0
3
…
Very
High
High
Income Income
Low
Incom
e
Mid
Incom
e
3.6
3.8
4.4
4.8
4.5
7.8
7.9
6.2
8.1
7.8
8.0
12.0
12.1
11.4
10.5
11.0
12.0
12.6
4
15.6
16.3
14.5
11.2
13.2
14.9
16.0
5+
19.3
21.5
18.9
13.5
16.6
17.7
19.6
Try out the 1995 NPTS transferability tool:
http://cta.ornl.gov/NPTS
2001 NHTS
On-line Table Generator
• Registration required, however, registration is
“immediate.”
• Generates SAS program without your
knowing much SAS.
• Includes the proper weights! Very important.
• Easy way to examine patterns, can help
identify relevant variables for regression or
other statistical test.
2001 NHTS On-Line Table Generator
Select variables of interest
SAS output listing file
Output to spreadsheet
Stay Connected
http://www.dot.gov/ctpp
http://www.TRBcensus.com
http://nhts.ornl.gov