Last week, I asked why Summary File 1 would answer the question, "How many Koreans live in Anchorage?" but not "How many Russians live in Anchorage?"
The answer is that Summary File 1 contains race data and not ancestry data. As I explained back in Week 3, Korean is a subcategory of the "Asian" race category. Only the race categories of American Indian and Alaska Native; Asian; and Native Hawaiian and Other Pacific Islander are subdivided. Hispanic origin is subdivided into Mexican, Puerto Rican, Cuban and Other Hispanic. As we know from Week 3, Hispanic is not a race, but an ethnic group. Descent from Russia, or from any other country or group I didn't name back in Week 3 is considered by the Census Bureau to be an ancestry group and not a race nor an ethnic group. Ancestry is a sample data question and the first time we'll see it reported will be in Summary File 3, due out June to September *2002*.
=============NEW BUSINESS: CENSUS GEOGRAPHY==============
Last week, I asked you to look at the release schedule available at [http://www.census.gov/population/www/censusdata/c2kproducts.html]. If you haven't done so yet, please do it now. Pay close attention the column marked "Lowest Level Geography." Ask yourself two questions:
Do I understand what these levels are?
Why doesn't everything go down to the block level?
BASIC CENSUS TERMS EXPLAINED
To answer the first question, I am going to define the most common Census and geography terms, then I will direct you to resources that will tell you much more than you ever wanted to know about census geography. The definitions below borrow heavily from the "Geographic Terms and Concepts" page from the Census Bureau web site [http://www.census.gov/geo/www/tiger/glossry2.html].
Census Block (commonly known as Block) - Census blocks are areas bounded on all sides by visible features, such as streets, roads, streams, and railroad tracks, and by invisible boundaries, such as city, town, township, and county limits, property lines, and short, imaginary extensions of streets and roads. Generally, census blocks are small in area; for example, a block bounded by city streets. However, census blocks in remote areas may be large and irregular and contain many square miles. Nationwide, there are 10 million census blocks. Blocks vary in population. My block in Douglas, AK only has 23 people in it. My parents' Census Block in California has 81 people living in it.
Block Group - A block group (BG) is a cluster of census blocks having the same first digit of their four-digit identifying numbers within a census tract. For example, block group 3 (BG 3) within a census tract includes all blocks numbered from 3000 to 3999. BGs generally contain between 600 and 3,000 people, with an optimum size of 1,500 people. Most BGs were delineated by local participants as part of the U.S. Census Bureau's Participant Statistical Areas Program. The U.S. Census Bureau delineated BGs only where a local, state, or tribal government declined to participate or where the U.S. Census Bureau could not identify a potential local or tribal participant.
Census Tract - Census tracts are small, relatively permanent statistical subdivisions of a county delineated by local participants as part of the U.S. Census Bureau's Participant Statistical Areas Program. The U.S. Census Bureau delineated census tracts in situations where no local participant existed or where local or tribal governments declined to participate. The primary purpose of census tracts is to provide a stable set of geographic units for the presentation of decennial census data. This is the first decennial census for which the entire United States is covered by census tracts. Census tracts vary considerably in size. My parents' census tract in California is only a few blocks wide, while my census tract in Douglas, AK is the ENTIRE island of Douglas, an area of over 75 square miles!
In addition to the terms above, here are some definitions that have special relevance to Alaska:
Census Designated Place - CDPs are delineated to provide data for settled concentrations of population that are identifiable by name but are not legally incorporated under the laws of the state in which they are located. Examples of CDPs in Alaska include Alpine, Gustavis, Happy Valley, Klukwan and Y. Why .'Y'? Because the Census Bureau usually names places according to what the locals call it. In the case of .'Y', they live near the y-shaped junction of a couple of highways. From the time people moved there, they've been calling it .'Y'. I've heard that Census people went to folks in .'Y' and begged them to call their settlement by a less puzzling name, but the independent Alaskans there wouldn't budge.
American Indian Area, Alaska Native Area, Hawaiian Home Land - There are both legal and statistical American Indian, Alaska Native, and Native Hawaiian entities for which the U.S. Census Bureau provides data for Census 2000. The legal entities consist of federally recognized American Indian reservations and off-reservation trust land areas, the tribal subdivisions that can divide these entities, state recognized American Indian reservations, Alaska Native Regional Corporations, and Hawaiian home lands. The statistical entities are Alaska Native village statistical areas, Oklahoma tribal statistical areas, tribal designated statistical areas, and state designated American Indian statistical areas. Tribal subdivisions can exist within the statistical Oklahoma tribal statistical areas.
Alaska Native Village Statistical Area (ANVSA) - ANVSAs represent the settled portion of Alaska Native villages (ANVs), which constitute tribes, bands, clans, groups, villages, communities, or associations established as part of the Alaska Native Claims Settlement Act of 1972, Public Law 92-203, as amended by Public Law 94-204. Examples of ANVSAs include Akhiok, Circle, Ivanof Bay and White Mountain.
The Census Bureau has created several new geographical entities for Census 2000. Some are more useful than others. I wish to highlight one helpful area and one area I think will cause more problems than it solves.
The Good Zip Code Tabulation Areas (ZCTA) - The U.S. Census Bureau's approximation of the delivery area for U.S. Postal Service 3- and 5-digit ZIP Codes, based on the residential mailing addresses in the Census Bureau's Master Address File. The delivery areas are adjusted to encompass whole census blocks to enable the Census Bureau to tabulate census data for both 3- and 5-digit ZCTAs. According to the Census Bureau, ZCTAs recognize ZIP Codes that are dedicated entirely to post office boxes in rural areas. There are approximately 45,000 ZCTAs nationwide. Data for ZCTAs started coming out with the release of Summary File 1. Since many people (and their realtors) tend to view neighborhoods by Zip Code, I feel the ZCTAs will earn a place in many librarians' hearts. If you want more detail about ZCTAs, see [http://www.census.gov/geo/ZCTA/zctafaq.html].
The Ugly - State legislative district (SLD) - The area represented by a member of the upper or lower chamber of a state legislature. Ten States, Arkansas, California, Florida, Hawaii, Kentucky, Maine, Maryland, Minnesota, Montana, and Texas declined to provide SLD boundaries. On the surface, this new geographical unit appears to be a godsend. Who (especially at a State Library) wouldn't want to rattle off detailed demographics to a state legislator. The legislator would have a clear picture of her district's population and housing and the librarian would quickly earn a reputation as a fount of wisdom. What a deal!
The bad news is that the boundaries for State Legislative Districts are PRE-REDISTRICTING. I was told by our Census field representative that the State Legislative Districts WOULD NOT be updated to reflect new boundaries. To me, that means the SLDs will become a source of confusion on the redistricting dust has settled. Legislators and other may ask for demographics by district and we run the risk of giving them bad information by simple running a table or map for the SLDs.
For more on geographic changes to Census 2000, see one of the resources below.
Geographic Terms and Concepts [http://www.census.gov/geo/www/tiger/glossry2.html] - Detailed definitions for Census geography terms. Often has several paragraphs for each term.
Geographic Changes for Census 2000 + Glossary [http://www.census.gov/geo/www/tiger/glossary.html] - Detailed explanations for new and redesignated types of areas in Census 2000.
Geographic Areas Reference Manual [http://www.census.gov/geo/www/garm.html] - The 15 volume Geographic Areas Reference Manual describes in great detail the basic geographic entities the Census Bureau uses in its various data tabulations and documents the purposes, definitions, standards, criteria, and procedures used to select, define, delineate, and revise these geographic entities.
US Census Bureau Geography Topics [ http://www.census.gov/geo/www/] - good set of links to everything geographical about the Census, even how to get a job as a Census geographer.
Confidentiality, mostly. If publishing statistics for a block would result in people being readily identifiable, then it would not be published. For example, if you asked for the number of people, by block, of Swedish decent, who took an hour to commute by bicycle, you would likely not get an answer from American Factfinder. More detail on the Census Bureau balances confidentiality with its mission of informing the nation can be found on page 81 of the Encyclopedia of the U.S. Census, edited by Margo J. Anderson, OCLC# 43894199, ISBN# 1568024282.
Alaska geography for the 1990 Census was prepared largely from 1950s maps. I learned this startling fact at an April workshop on the 2000 Census. Our Department of Labor and Workforce development spent years fixing this problem, once this federal error was discovered. Ingrid Zaruba and Kathryn Lizik (more on them in a week or two) worked on fixing Alaskan geography in a number of ways. They even drove the ENTIRE Alaskan road system to note all of the settlements and roads so the 2000 Census enumerators could do their work properly.
What this means to us Alaskans, is that numbers from prior Censuses, especially for rural areas, may be directly comparable to the new 2000 Census figures. If you want to be sure, pull a map of the area being examined from both the prior census and the current census. 2000 Maps are available through American Factfinder, and maps from prior Censuses should be as close as your nearest Federal Depository Library.
There have also been changes to our cities and boroughs since 1990. Specifically,
The Skagway-Yakutat-Angoon Census Area became Skagway-Hoonah-Angoon Census Area (02232), and Yakutat City and Borough (02282).
The Denali Borough (02068) was created from parts of Yukon-Koyukuk Census Area and Southeast Fairbanks Census Area.
Even if you don't live in Alaska, some of your boundaries may have changed. Take a look at [http://www.census.gov/geo/www/tiger/rd_2ktiger/ctychng.html] to see if this has happened to you.
Daniel Cornwall, Member Alaska Library Association Government Documents Roundtable.
If you find any part of this tutorial useful, you may use it in training materials with proper attribution, and if you drop me a line at email@example.com telling me how you're going to use it. Thanks!
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This Page was last updated July 7, 2001. (Links checked September, 2010)