Secondary Data

Census and TIGER

Why Secondary Data?

Context (geographic, temporal, social) for primary data.

Secondary data may provide validation for primary data

Secondary data may act as a substitute for primary data.

Types of Secondary Data

How to find it

Official

Unofficial

Unofficial Secondary Data

Sources Private research results Research reports, research papers,

textbooks Opinion polls Market research On-line databases Anecdotal/hearsay

Official Secondary Data Sources

Agriculture Business/

Industry Crime Education Finance

Energy Environment Health Transport Weather

Agriculture

USDA

FAO

Farm Bureau Federation

Babcock

Business / Industry

STAT-USA/Internet (US Dep. of Commerce, not free)

Consumer Expenditure Surveys(Bureau of Labor Statistics)

Internal Revenue Service

Crime

Bureau of Justice Statistics

FBI

Crime & Justice Electronic Data

Abstracts

http://www.ojp.usdoj.gov/bjs/d

tdata.htm

Education

National Center for Education Statistics

School District Data Book (ORST)

National Science Foundation

UNESCO

Environment

EPA Envirofacts EPA EnviroMapper

Facility InformationHazardous Waste DataSuperfundToxics Releases InventoryWater Discharge Permits

ScoreCard Right To Know

Health

National Center for Health Statistics (CDC)

Social Security Administration

Geophysical

NOAA

USGS

US Forest Service

Soil Conservation Service

Dep. of Natural Resources (DNR)

Dep. of Conservation

Transportation

Department of Transportation

Bureau of Transportation Statistics

State Highway Departments (CA, TX)

Regional Transport Authorities

Census

Structure Timing Population Organization Analysis Presentation Geographical Hierarchy Variables

Census Geographical Hierarchy

RegionDivision State

County County subdivision

Place (or part) Census tract (or part)

Block group (or part) 9 mio. Census blocks

Census Household Variables

Number of persons Age and gender Race Language Income and

poverty Education Employment Citizenship

Vehicles for commute Disability Homeownership status Vacancy Rent and value of

housing Age and type of

structure Plumbing and Kitchen Heating

Examples of Census Variables

Accommodations Agriculture Alaska Natives Arts,

Entertainments Asians Assets Assistance

Capital Expenditures

Child Care/Support Commodity Flows Communications Consumer Income County Business

Patterns County/City

Government

TIGER

Topologically Integrated Geographic Encoding and Referencing system

Based on USGS topographic maps but majorly augmented

Contains no elevation data

No copyright

No street names

American Community Survey

Annual

Long

Representative – not comprehensive

Master Address File for sample selection

Wisconsin a forerunner

Pro’s and Con’s of Secondary Data

Advantages Cheap Timeliness Access to

people/organizations that we wouldn’t have access to otherwise

Less post-processing

Disadvantages

Collection method unknown

Lack of control

Data Vendors

Remote Sensing Value adding to public data Utilities Market Research GIS Vendors University Extensions World Bank

Before YOU Purchase Data

Accuracy

Compatibility

Lineage and metadata

Who owns the copyright?