Census 2010: Accessing Census Data THURSDAY, July 21, :30am

Quick Review 2010 decennial data is “short-form” only – demographic characteristics; ACS now source of “long-form” type of data Census Data released in two “flavors” – Aggregate Data Microdata A third type of data product identifies geographic boundaries Aggregate Data released in a variety of products, differing in content, geographic specificity and temporal coverage Microdata has flexibility of individual level information, but balances this by only gross geographic detail

Access and Resources Aggregate data resources Microdata resources Geography resources Documentation resources Visualization resources Local resources

Access and Resources Aggregate resources: Current: American Factfinder, DataFerrett, Uexplore/Dexter Historical: NHGIS, ICPSR, Historical Census Browser Microdata resources Online Analysis: SDA & IPUMS Extract/Download: IPUMS, ICPSR, NBER, DataFerrett, Census Geographic: Census, MABLE/Geocorr, IPUMS Documentation: IPUMS, AFF2, ICPSR Visualization: Social Explorer Local Resources: DOF/DRU, SDC’s, UC DATA, DataLab

Aggregate Data Resources

The “old” American Factfinder

The “new” American Factfinder

Alternative to AFF: FTP Full Files

Same FTP Options for ACS

Historical Census Data Browser

Micro-data Resources

Survey Documentation and Analysis (SDA) and the Integrated Public Use Microdata Samples (IPUMS)

The Integrated Public Use Microdata Samples

at the Minnesota Population Center IPUMS-USA IPUMS-USA Harmonized data on people in the U.S. census and American Community Survey, from 1850 to the present IPUMS-USA Harmonized data on people in the U.S. census and American Community Survey, from 1850 to the present. IPUMS-USA IPUMS-CPS IPUMS-CPS Harmonized data on people in the Current Population Survey, every March from 1962 to the present IPUMS-CPSImportant! Harmonized: Questions asked change over time: How to make data comparable? Integrated: Multiple data collections & surveys simultaneously available Microdata: The underlying individual-level data is available, not just pre-defined tables.

The American Community Survey and the Current Population Survey CPS – Long-running monthly survey (dating back to the 1940’s) focused on labor force characteristics (unemployment, earnings, hours worked). ~ 55,000 sample HH’s, multiple interviews, personal In addition to the basic monthly questions, additional modules are “piggy-backed” onto the survey to provide more depth on particular topics. Most widely used supplement is the Annual Social and Economic Supplement (ASEC) - aka Annual Demographic Survey or the March Files. (~100,000 HH’s) In-depth survey – lots of detail about sources of income, work, occupational, hours, etc. (as well as core demographic information on race/ethnicity, nativity, age, sex, educataion)

The American Community Survey and the Current Population Survey ACS – “New” continuous survey, replaces the long form of the decennial census, first fully implemented in 2005 (non- institutionalized) and 2006 (institutionalized). ~ 2,000,000 HH’s annually, mixed mail-in/personal interviews Substantial overlapping content with CPS Broader range of content, somewhat less detail Larger sample sizes allow for greater geographic detail

The American Community Survey and the Current Population Survey Aggregate Microdata vs.

The Integrated Public Use Microdata Samples at the Minnesota Population Center Tremendous centralized documentation Many “value-added” data items Wonderful extraction engine (if downloading data) Multiple statistical Packages supported Online Analysis also possible

The Integrated Public Use Microdata Samples Online Analysis Links

What is SDA? What can you do with SDA? The parts of the SDA interface MenuMenu Variable ListVariable List Active variablesActive variables Analysis SpecificationAnalysis Specification The Basics of SDA

1. Parts of the SDA interface 2.Finding data/variables/subjects - search - documentation 3.Analysis - Components - rows, columns, selection, controls Procedures - crosstabs, means, correlations 4. Aids in Analysis Recoding Recoding Saving new variables Saving new variables Downloading Downloading But… Before we go live…. Part II. Working with SDA

What is SDA? SDA (Survey Documentation and Analysis) is a set of programs for the documentation and Web-based analysis of survey data. It was developed and is maintained by the Computer-assisted Survey Methods Program (CSM) at UC Berkeley. It was developed as a companion program with CASES (Computer Assisted Survey Execution Program), a package for collecting survey data based on structured questionnaires, using a variety of modes of data collection. It operates on a transposed file structure, which makes analysis of datasets, especially large datasets, extremely fast. The Basics of SDA

What is SDA? SDA (Survey Documentation and Analysis) is a set of programs for the documentation and Web-based analysis of survey data. It was developed and is maintained by the Computer-assisted Survey Methods Program (CSM) at UC Berkeley. It was developed as a companion program with CASES (Computer Assisted Survey Execution Program), a package for collecting survey data based on structured questionnaires, using a variety of modes of data collection. It operates on a transposed file structure, which makes analysis of datasets, especially large datasets, extremely fast. Part I. The Basics of SDA

What data is available in SDA? LOTS! Many popular social science datasets (e.g. the GSS, the ANES, the PUMS from the Decennial Census, the ACS, the CPS Annual Demographic Files,…… can be found in SDA format. Many archives (ICPSR, IPUMS, CPANDA, Roper, SDA, UCDATA….) provide at least some of their holdings in SDA format. Part I. The Basics of SDA

Multiple Census Samples at IPUMS (

And CPS (March files) data, as well (

What can you do with SDA? SDA can be used to: learn about a dataset (metadata, paradata)learn about a dataset (metadata, paradata) search for variables of interestsearch for variables of interest investigate sample sizes and variable distributionsinvestigate sample sizes and variable distributions perform statistical analysesperform statistical analyses transform, manipulate and create variables for each unittransform, manipulate and create variables for each unit extract and download subsets or full datasetsextract and download subsets or full datasets The Basics of SDA

The four parts of the SDA interface Action MenuAction Menu Variable ListVariable List Active VariableActive Variable Analysis SpecificationAnalysis Specification Part I. The Basics of SDA

Action Menu

Collapsed Variable Tree

Active Variables

Analysis Specification

2.Finding data/variables/subjects Online SDA codebook Online SDA codebook IPUMS detailed documentation

Analysis – Components - rows, columns, selection, controls Procedures - crosstabs, means, correlations Screens will vary depending upon what procedure you are using. Start with exploratory – frequencies, cross-tabulations Working with SDA

The variables you are interested in Who to include in the table

Aids in Analysis Recoding Recoding Saving new variables Saving new variables Downloading Downloading Part II. Working with SDA

age (5-18) Selects, but does not collapse age (r: 5-18)Selects AND Collapses age (d: 5-18)Collapses, but does not select age (c:13,5)Collapses into categories of width w age (c:st,w) starting with value st Recoding variables – on the fly Recoding variables – Web interface Can be used in row, column, control (Crosstabs)

Question 1: Use the CPS or ACS? Question 2: What is the desired level of analysis (person, family, household)? Question 3: Who should be excluded? (How to limit to family households, or only (How to limit to family households, or only particular age groups, or….? particular age groups, or….?

DataFerrett Content

Geographic Resources

Social Explorer ACS, 2010 Census

Selected Data Resources at Berkeley Library Data Lab SDA (Survey Documentation & Analysis) Statewide Database California Census Research Data Center The Econometrics lab Thomas J. Long Business & Economics Library

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