Economic & Demographic Research Tools
Research Tools
All materials listed on this page are
produced by Economic and Demographic Research, Fairfax County
Department of Neighborhood and Community Services.
Some of the items below are available in
Adobe Acrobat (.pdf) format. In order to view the Adobe Acrobate
files, you must have
Adobe Acrobat Reader installed on your computer. The Adobe
Acrobat Reader software is available free. The American
Community Survey tools are Excel files.
Which Data Should I Use
When estimates from Fairfax County and the Census Bureau are compared they often differ. The estimates differ because different methodologies and techniques are used to produce them. We have developed some guidelines to help data users determine which data source to use when comparing Fairfax County data, Decennial Census data and American Community Survey data.
Which data should I use
guidelines
American Community Survey (ACS) Tools
Combining Estimates and
Calculating the Associated Margin of Error (MOE)
Tool allows data users to combine
American Community Survey estimates across categories or geographies and
calculates the MOE for the combined estimate. For example, a data
user may want to combine the estimates from several age categories.
Calculating
Percents and the Associated Margin of Errors (MOEs) from
Estimates
Tool allows data users to enter American
Community Survey numerical estimates and MOEs and transforms these
estimates into percents. For example, a data user who combined age
categories using the tool above may want to find out the percent and
MOE of the total population this age group represents.
Statistical
Significance Calculator
When the difference between estimates is
statistically significant it means that at a specified level of
confidence there is a real or measurable difference between the values.
It does not mean that the difference is large or important.
This tool allows data users to measure the statistical significance
between two American Community Survey estimates at three different levels
of confidence - 90 percent, 95 percent and 99 percent. In addition, the
tool calculates the associated confidence intervals for the estimates at
these three levels of confidence.
Percent Change
Calculator
Tool calculates the percent change between
two American Community Survey estimates and calculates the margin of
error of the percent change.
Coefficient
of Variation (CV) Calculator
Tool calculates the associated coefficients of
variation of a series of American Community Survey estimates and margins
or error. The coefficient of variation is a relative measure
of the variability of the estimate and is expressed in this
tool as a percentage. The lower the coefficient of variation,
the more precise and stable is the estimate.
Survey Research Tools
Common Pitfalls in
Conducting a Survey
The
intent of this brochure is to provide a brief review of potential
problems that may occur during the survey research process.
Survey
Questionnaire Design
This
brochure provides a brief guide to planning, developing, and testing a
questionnaire for use in survey research.
Overview
of Sampling Procedures
The
purpose of this brochure is to provide an overview of the sampling
procedures available to a researcher. The differences between the various
sampling procedures are discussed and examples are provided to illustrate
the use of these procedures.


Website Survey