Harvard Government 90dn Lecture 2

Government 90dn Mapping the Census Lecture 2: Data from the Census: Strategies to understand and acquire it Sumeeta Srinivasan [email protected] Reference: Unlocking the Census, Ch 2; www.census.gov

Standard Format for Classes Lecture (1 hour or less) Followed by or interspersed with discussion Discussion: based on article Lab Exercises (1-2 hours) – All due Nov 20th 2-? hours (may extend beyond class times) that should be ideally returned to the instructor before the next lab

Evaluation Lab exercises (5):

25%

5 points each for Labs 1-5

Final project:

55%

Proposal (5%), presentation (10%) and report (40%)

Participation:

20%

Final Project Project proposal by November 1st Should include spatial and non-spatial data description Background research (context) and motivation Research questions, Proposed methodology

Project presentation on December 5th or 12th Project summary report Jan 1st

Course Topics 1. 2.

3.

Introduction to Census Census Data Basics Data Types Databases Introducing Maps GIS Cartography

Applications Demography Economics Housing and Transportation

Research Methods Writing Proposals and Papers Quantitative methods

Geographic Information System Container of maps Spatial decision support system: Method for revealing patterns and processes in geographic information

Example: The Hispanic Population: 1990-2000 Growth and Change

Source: www.sabresystems.com/whitepapers/hispanic_population.pdf

Sources of Data US Census Local Agencies (Massgis in Massachusetts other State agencies in other states) Harvard Map Library

Linking to Internet Sites Geography Network Example

US Census www.census.gov z z

TIGER Maps Summary File (SF) Tables

Census Tracts (TIGER) Small, relatively permanent statistical subdivisions of counties delineated by local committees in accordance with Census Bureau guidelines between 1,000 and 8,000 people (in general) 1,700 housing units or 4,000 people homogeneous population characteristics (economic status and living conditions) normally follow visible features may follow governmental unit boundaries and other non visible features more than 60,000 census tracts in Census 2000

State Census Tracts

County Census Tracts

City Census Tracts

Census Blocks Groups Block groups (BGs) are the next level below census tracts in the geo-graphic hierarchy - a subdivision of a census tract -400 housing units, with a minimum of 250, and a maximum of 550 housing units -follow clearly visible features, such as roads, rivers, and railroads

Census Block Groups

Census Blocks Smallest geographic area for which the Census Bureau collects and tabulates decennial census information. Block boundaries are visible (street, road, stream, shoreline, etc.) or nonvisible (county line, city limit, property line, etc.) features.

Census Blocks

Other Census TIGER Layers

Summary File (SF) Tables American Factfinder

SF1 Tables

SF2 Tables

SF3 Tables

Download Census Data Table

Download Census Data Table

Data Types

Data Types Database Compatible

Clean Data in Excel

Delete unnecessary rows

Clear Formatting

Highlight Cells

Save Database Saved as .CSV or .DBF

Add in ArcMap (GIS)

Add Data Table in ArcMap

Download Shapefile

Add Shapefile

Select County Features and Export

Check Fields to Join Problem! Fields are not the same

Create New Fields

Ready to Join

Join Data

Fields Added to Tracts Table

Number Fields Quantities will only appear with number fields

Common Datasets

U.S. Census Maps and U.S. Census Tables

Common Datasets Zip Codes z

Use with U.S. Census data or Geocoding

Place Geocodes: FIPS Codes Federal Information Processing Standards Codes Developed by the National Institute of Standards and Technology Codes for Place Names Throughout the World countries states/provinces counties metropolitan statistical areas (MSA’s) cities places - indian reservations, airports, and post offices in the US

Place Geocodes: Hierarchy FIPS CODES Country: US State: 42 (Pennsylvania) County: 003 (Allegheny) Minor Civil Division: 85188 (Wilkinsburg) CENSUS CODES

Tract: 0501 Block Group: 3 Block: 12 (US420030501312) Parcel (Block & Lot#)

Keys All attributes or sets of attributes that have the property of row uniqueness are candidate keys

Examples

SQL Query SELECT * FROM Off199803 WHERE Context = “BURGLARY” ORDER BY Crnumber;

GIS RQBE

Result