Download presentation
Presentation is loading. Please wait.
Published byRosa Ventry Modified over 9 years ago
1
But what about the ACS? What is the American Community Survey? Replacement of the Long Form Continuous Survey Methodology Conducted Monthly
2
According to the Census Bureau The ACS is… A large, continuous demographic survey Produces annual and multi-year estimates of the characteristics of the population and housingProduces annual and multi-year estimates of the characteristics of the population and housing Produces characteristics, not a population countProduces characteristics, not a population count Produces information for small areas including tracts, block groups and population subgroups - updated every yearProduces information for small areas including tracts, block groups and population subgroups - updated every year Key component of reengineered 2010 censusKey component of reengineered 2010 census
3
ACS Facts About 1 in 40 Households Sampled per year 250,000 Households Sampled per month Same Transportation questions as 2000 Long Form Decennial Long Form is History, Kaput, Gone!
4
But why change and have an ACS? Eliminate the Census Long Form for 2010 and Thereafter Eliminate the peak in Congressional funding Eliminate the peak in hiring andtraining Census takers
5
How does the ACS work? Three Methods of Data Collection 1. Mail Self-administered mail-out/mail-back 1. Mail Self-administered mail-out/mail-back 2. Telephone Computer Assisted Telephone Interviewing (CATI) 3. Personal Visits Computer Assisted Personal Interviewing (CAPI ) 1:3 3. Personal Visits Computer Assisted Personal Interviewing (CAPI ) 1:3
6
When will it start? It already has
7
American Community Survey Data Release Timetable Type of Data Population Size of Area Data for the Previous Year Released In the Summer of: 2006 2007 2008 2009 2010 2011 2012+ Annual Estimates 65,000+ 3-year averages 20,000+ 5-year averages Down to Census Tract and Block Group
8
Aug. 2008 Aug. 2010 In August of 2006 you got 2005 data
9
Aug. 2008
10
April 1 August Dec. (PL 94-171) Aug. 2010 2010
11
Decennial Census ACS Sample: 1 in 6 Hhlds (17% Sample) Sample: 1 in approx 40 households each year (2.5%/yr 12.5% @ 5 yrs) Time reference: April 1, 2000 or April 1, 2010 (Last Week) Time reference: Continuous including all 12 months One time data collection every 10 years Requires accumulation over multiple years for small area reporting Main differences between Census Long Form and ACS
12
Some Emerging Issues People might be counted twice, e.g. once at summer cabin and once at a “permanent home”. Or once at university and once at parent’s home. Areas with seasonal populations, e.g. due to “snow bird” migration, and due to school enrollments, with housing occupancy that varies from 95% to 40% might show up as 80%.
13
Mail back rates from Minority populations are significantly lower Mail back rates from Minority populations are significantly lower Source: C2SS test Tracts with 75% or more of a population reporting… % of mail- backs White60.5% African American 34.9% American Indian/Alaska Native 16.6% Asian58.6% Hispanic34.2%
14
Different Non Response Follow-up rates based on mail back returns That is, in areas with low mail- back returns, a higher NRFU rate will be implemented That is, in areas with low mail- back returns, a higher NRFU rate will be implemented Thus, standard errors will be more consistent across neighborhoods Thus, standard errors will be more consistent across neighborhoods
15
Sample Error is larger because the number of census forms collected each year are smaller. Changes of plus or minus 2% may be due to Sample Error and do not reflect measurable change. Understanding Sample Error
16
Statistical Significance Tests Standard Error = Margin of Error / 1.65 But what about MOEs for 2000 data? 90% Confidence Comparing ACS directly to 2000 Data can be iffy Comparing ACS directly to 2000 Data can be iffy
17
http://www.census.gov/prod/cen2000/doc/sf3.pdf Chapter 8: Accuracy of the Data Estimate Standard Errors Adjust for Survey Design Factors - Table C
18
Things to consider when trying to compare ACS directly to Decennial data Things to consider when trying to compare ACS directly to Decennial data Seasonality 12 months instead of "April 1") (different jobs and workers, especially in summer Group Quarters currently not in 2005 ACS Non-response follow-up differences Data collection period ACS is very long, compared to very short in decennial Sample Sizes and MOEs ACS is about 1 in 40 households compared to about 1 in 6
19
Data Release Schedule 1-year data in 2006 (every year thereafter) 3-year data in 2008 ( every year thereafter) 5-year data in 2009 ( every year thereafter) Plus the within-year release schedules
21
Within-Year Data Release Schedule for 2005 Data August 15, 2006 Demographic and SocialCharacteristics Demographic and Social Characteristics August 29, 2006 Economic Characteristics; Public Use Microdata File October 3, 2006 Housing Characteristics; Narrative Profiles; Workplace Base Tables November 14, 2006 Selected Population Profiles
22
August 15th Demographic and Social August 15th Demographic and Social
23
August 29th Economic Characteristics August 29th Economic Characteristics and PUMS too
24
October 3rd Housing ---- Etcetera October 3rd Housing ---- Etcetera i.e. Workplace Tables
25
October 3rd Etcetera October 3rd Etcetera … For Workplace Geography
26
November 14 Selected Population Profiles November 14 Selected Population Profiles
27
Where do I get ACS? FactFinder
28
There is a lot here Even built in significance tests
30
Note difference between DC and NJ
31
A place to start mining ACS Go to Detailed Tables
32
Check out all the Tabs
33
Pick Your Geography
34
State...
35
Places...
36
Then Tables...
37
Note the Tabs
38
Keyword Search
39
“B” and “C” Tables
40
Full Table – PASSED FILTERING Statistically too Small
41
Collapsed Table
42
You Can Also Download the Results
43
Download Options...
44
My Selection
45
What I took home
46
1. Resident Person Information 2. Resident Household Characteristics 3. Worker/Workplace Data ACS CTPP Data Profiles Brand New CTPP Data Product
47
States, Large Cities, MSAs Resident Person Information for… Mode to work Travel Time to work Departure Time for work Mode to work by Travel Time Mode to work by Average Travel Time Florida Statewide data
48
Mode to work by Vehicles Available Vehicles Available in Households Household Size by Vehicles Available Vehicles Available by Workers in Household Persons in Households by Workers in Household The Nation, States, All PUMAs, Counties and Places over 65k Resident Household Characteristics for.. Wisconsin Statewide data
49
States, Counties and Places over 65k Worker / Workplace Data for… Total Workers -- Travel Time to work -- Mode to Work Get ACS CTPP Data Profiles online or from the Class Workbook CD
50
On-going concerns about ACS Will the sample be sufficient for small geographic area reporting? Will tract and BG and TAZ reporting occur after 60 months of data collection?Will the sample be sufficient for small geographic area reporting? Will tract and BG and TAZ reporting occur after 60 months of data collection? Will Congress continue to fund the survey continuously, especially if CB asks for increasing budgets to meet the sample size requirements? (or will CB decrease the sample size, resulting in loss of small area tabulation?) Group QuartersWill Congress continue to fund the survey continuously, especially if CB asks for increasing budgets to meet the sample size requirements? (or will CB decrease the sample size, resulting in loss of small area tabulation?) Group Quarters
51
What Were the Transportation Concerns in 2005? Will there be flow data? Flows are in serious jeopardy due to thresholds and disclosure proofing?Will there be flow data? Flows are in serious jeopardy due to thresholds and disclosure proofing? Will there be a CTPP like package? Who will organize it, negotiate with the CB and contract with the CB. Timing of release? Cost?Will there be a CTPP like package? Who will organize it, negotiate with the CB and contract with the CB. Timing of release? Cost? Will there be TAZs? How might they change, what tables will be available, for what geographies?Will there be TAZs? How might they change, what tables will be available, for what geographies?
52
On-Demand Technical Assistance $930,000 Training$625,000 Research$920,000 Data Products$2,980,000 Oversight Activities$465,000 TOTAL $5,920,003 Consolidated CTPP Purchase AASHTO SCOP Census Data Work Group CTPP Technical Group
54
Will there be flow data? Flows are in serious jeopardy due to thresholds and disclosure proofing?Will there be flow data? Flows are in serious jeopardy due to thresholds and disclosure proofing? Will there be a CTPP like package? Who will organize it, negotiate with the CB and contract with the CB. Timing of release? Cost?Will there be a CTPP like package? Who will organize it, negotiate with the CB and contract with the CB. Timing of release? Cost? Will there be TAZs? How might they change, what tables will be available, for what geographies?Will there be TAZs? How might they change, what tables will be available, for what geographies? Current Expectations
55
NCHRP 8-48 Guidebook Using the American Community Survey Data for Transportation Planning ($350K) Expected May 2007 NCHRP 8-36 Project Disclosure Avoidance Techniques to Improve ACS Data ($75) Expected Next Year Census Geography and Participant Statistical Areas Program — Hoping to have TAZs included ACS Use Capacity Building Peer Exchange, SCOP Working Group/FHWA, Spring 2007 ACS related activities currently underway
56
Census Data for Transportation Planning Preparing for the Future Irvine, California May 11-13, 2005 http://www.trb.org/conferences/censusdata
57
Now let’s go do some Statistical Significance Testing!
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.