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2010 Census Coverage Measurement Survey Update

2010 State Data Center/Census Information Center

Steering Committee Meeting

February 23, 2010

Thomas MuleUS Census Bureau

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CCM – Census Coverage Measurement

• Survey provides estimates of coverage error for people in housing units and for housing units:• Excludes group quarters and remote

Alaska• Includes Puerto Rico

• No intent to adjust the census

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Net Error

• Uses dual-system estimation, a sample capture-recapture technique

• Used in 1980, 1990, and 2000• Provides estimates of net undercount

and overcount• Key demographic groups• Specific geographic areas

• Requires independence from census

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Components of Census Coverage Error

• New objective for 2010• Provides estimates of:

• Correct enumerations – those included correctly by the census

• Erroneous enumerations – those included incorrectly by the census

• Imputations• Omissions – those missed by the census

• Key demographic groups and by census operations

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2000 A.C.E. Measurement Error

• 2000 coverage measurement program failed to detect erroneous enumerations• Many were census duplicates

• CCM Goal: Reduce nonsampling error from the 2000 Accuracy and Coverage Evaluation (A.C.E.)

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Sample Design of 2010 CCM

• Area sample of block clusters – groups of census collection blocks

• Population (P) Sample: Independent sample of housing units in block clusters. Recapture sample.

• Enumeration (E) Sample: Census enumerations in the same sample block clusters

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Independent Listing

• Independent listing of area sample• Canvass block cluster• List addresses of housing units and

potential housing units• Timing: August-December 2009

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Person Interview

• Laptop interview at independently listed addresses• Personal visit• Gather independent roster of people

• Probing questions about places where the person:• Should have been counted• Could have been counted

• Timing: August-October 2010

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Person Matching and Followup

• Match people collected in CCM to census person list• Computer• Clerical

• Search throughout the country• Computer nationwide search• Clerical search at places the person could have

been counted from the person interview• Person Followup (personal visit and telephone,

paper-based)• Timing: October 2010 – April 2011

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Current Plans for Estimation Domains for 2010

CCM• Estimation domains have not been finalized so products shown here are current plans

• Break into 3 Major Groupings:• Demographic/housing unit characteristic

groups• Geographic areas• Census operation results

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Examples of Estimation Domains for Demographic Groupings for People in

Housing Units

Demographic Groupings

Net Error Components of Census Coverage

Correct Erroneous Imputations Omissions

Race and Hispanic Origin

Yes Yes Yes Yes Yes

Tenure Yes Yes Yes Yes Yes

Age/Sex Groupings

Yes Yes Yes Yes Yes

Individual Years of Age

Yes No No No No

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Examples of Estimation Domains for Geographic Areas for People in Housing

Units

Geographic Areas Net Error

Components of Census Coverage

Correct Erroneous Imputations Omissions

Type of Enumeration Areas

Yes Yes Yes Yes Yes

Bilingual Mailing Blocks

Yes Yes Yes Yes Yes

Region Yes Yes Yes Yes Yes

Each State Yes UnderReview

UnderReview

UnderReview

UnderReview

Substate Estimates(county, places)

UnderReview

UnderReview

UnderReview

UnderReview

UnderReview

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Examples of Estimation Domains for Census Operations for People in Housing

Units

Census Operation/Results

Net Error

Components of Census Coverage

Correct Erroneous Imputations Omissions

Mail Return No Yes Yes Yes No

NRFU enumeration No Yes Yes Yes No

Operation Check-in Date Groupings

No Yes Yes Yes No

Coverage Followup No Yes Yes Yes No

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What about those people who should have been enumerated

somewhere else?

• A table to show people who should been enumerated outside our block cluster search area.• Same county• Different county in the same state• Different state

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Examples of Estimation Domains for HU Characteristics for Housing Units

Demographic Groupings

Net Error

Components of Census Coverage

Correct Erroneous Omissions

Occupancy Status Yes Yes Yes Yes

Tenure of Occupied Units

Yes Yes Yes Yes

Type of Structure(Single, Multi-units)

Yes Yes Yes Yes

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Examples of Estimation Domains for Geographic Areas for Housing Units

Geographic Areas Net Error

Components of Census Coverage

Correct Erroneous Omissions

Type of Enumeration Areas

Yes Yes Yes Yes

Region Yes Yes Yes Yes

Each State Yes UnderReview

UnderReview

UnderReview

Substate Estimates(county, place)

UnderReview

UnderReview

UnderReview

UnderReview

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Examples of Estimation Domains for Census Operations for Housing Units

Census Operation/Results

Net Error

Components of Census Coverage

Correct Erroneous Omissions

Field Verification No Yes Yes No

Nonresponse Followup Vacant/Delete Check

No Yes Yes No

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Housing units that were geocoded incorrectly

• A table to show housing unit geocoding results in relation to block cluster search area• Geocoded to block cluster• Geocoded one block outside of the cluster• Geocoded beyond one block outside of the

cluster

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Reducing Nonsampling Error in the CCM

• Part of Decennial review conducted by Director Groves

• Identified areas in the CCM where efforts can be made to reduce nonsampling error

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CCM Sample Size

• Reduced from 300,000 to 170,000 housing units

• American Indian Reservation and Hawaii sample remain same

• 1,000 target minimum state housing unit sample size

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2010 Evaluations and Assessments

• Evaluations• Goals

• Examine results of 2010 • Improve 2020

• Assessments• Every operation

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Thanks!

vincent.t.mule.jr@census.gov