State & County Quickfacts
QuickFacts tables are summary profiles showing frequently requested data items from various Census Bureau programs. Profiles are available at the national, state, and county level.
Census 2000 GatewayThe Census 2000 Gateway page is the central point for investigating data related to Census 2000. Not only can users access the data through this gateway, but also they can find background information about the data. Among the many links are data release schedules, links to the questionnaires, information about our many Census 2000 partners, rankings, reports, and a multitude of other useful information.
County Business PatternsCounty Business Patterns is an annual series that provides subnational economic data by industry. The series is useful for studying the economic activity of small areas; analyzing economic changes over time; and as a benchmark for statistical series, surveys, and databases between economic censuses. Businesses use the data for analyzing market potential, measuring the effectiveness of sales and advertising programs, setting sales quotas, and developing budgets. Government agencies use the data for administration and planning.
American FactFinderThe American FactFinder is an electronic system for access and dissemination of Census Bureau data on the internet. The system offers prepackaged data products and user-selected data tables and maps from Census 2000, the 1990 Census of Population and Housing, the 1997 Economic Census, and the American Community Survey. The system was formerly known as the Data Access and Dissemination System (DADS).
Imports & ExportsThe Census Bureau’s Foreign Trade division collects data on imports and exports. Data are tabulated many different ways: by country totals, by product totals, by state totals, etc. There are also many detailed on reports on specific commodities as well.
Technical Documentation
Another good tool to use for making sense out of all the data is the technical documentation. Technical documentation is essentially where all the various notes and other information used to explain the data itself are located. This background information about the data is formally called metadata. Most every data product the Census Bureau issues will have technical documentation associated with it to aid users in making sense of the statistics.
For an example, check out the technical documentation for one of the decennial census' most complicated data products -- Summary File 4. http://www.census.gov/prod/cen2000/doc/sf4.pdf [PDF]
Statistical Accuracy – Confidence and Error
In order to understand random sampling, you need to become familiar with a
couple of basic statistical concepts.
1. Error - This is that "plus or minus X%" that you hear about. What
it means is that you feel confident that your results have an error of no more
than X%.
2. Confidence - This is how confident you feel about your error level. Expressed
as a percentage, it is the same as saying if you were to conduct the survey
multiple times, how often would you expect to get similar results.
These two concepts work together to determine how accurate your survey results
are. For example, if you have 90% confidence with an error of 4%, you are saying
that if you were to conduct the same survey 100 times, the results would be
within +/- 4% of the fist time you ran the survey 90 times out of 100.
If you are not sure what sort of error you can tolerate and what level of confidence
you need, a good rule of thumb is to aim for 95% confidence with a 5% error
level.
Error is also referred to as the "confidence interval" and Confidence
is also known as "Confidence Level." In order to avoid confusion,
these concepts will simply be referred to as "Error" and "Confidence"
in this article.
** Excerpt from: http://www.custominsight.com/articles/random-sampling.asp
COMPARING DATAMost users are not just interested in what the statistics look like for a topic right now; they want to compare them with data from the past. Well, there are many variables one must consider when comparing data over time. Some of these differences include:
For example, when comparing data from one decennial census to the next, such as Census 2000 to the 1990 Census there are several differences that stand out right away:
Besides some of the major Census Bureau programs that are more commonly known such as the decennial and economic censuses, we conduct literally hundreds of other data collection programs. These many programs include demographic and economic surveys, projections and estimates, international programs, and on and on.
Economic Census
"How people use economic census data"
http://www.census.gov/epcd/www/ec97use2.htm#COMPETITION
ACS case studies
http://www.census.gov/acs/www/Downloads/ACS/Paper35.pdf
[PDF]