Comparing the American Housing Survey and the American Community Survey

Comparing the American Housing Survey and the American Community Survey


Hello and welcome to Comparing the American
Housing Survey and the American Community Survey. This webinar will explore the key differences
between these two surveys and give you the information you need to decide when to use ACS or AHS data. Let’s get started. The American Housing Survey (also known as the AHS) and the American Community Survey (also known as the ACS) are valuable sources
of information for studying the US housing stock. Both surveys ask questions on similar housing
topics. So, which source should you use to answer
your housing questions? Let’s start by looking at what the American
Housing Survey is all about. The American Housing Survey is often called
the nation’s most comprehensive housing survey. The AHS provides accurate, up-to-date information
on housing quality, housing costs, and neighborhood assets, along with topical information on
unique housing concerns. Policymakers, researchers, and housing professionals
use AHS data to assess and monitor the nation’s housing needs and to stay up to date on what’s
going on in the housing market. The AHS collects some information about the
people that occupy the households being surveyed, but its main purpose is to provide data on
the nation’s housing units. How does the American Community Survey compare? Let’s take a closer look. The American Community Survey is another premier
source for vital housing data. Different from the AHS, the ACS also collects
detailed population information—including data on jobs and occupations, educational
attainment, and other topics that are not related to housing. State and Federal governments use the ACS
data to determine how more than $675 billion in federal and state funds are spent on infrastructure
and services each year. Now, we’ll look at who sponsors the AHS
and the ACS. The US Department of Housing and Urban Development,
or HUD, sponsors the American Housing Survey and the US Census Bureau, or Census, administers
it. That means HUD pays for the AHS and applies
the agency’s deep understanding of the nation’s housing market to determine the content—including
what questions to ask, what metropolitan areas to survey, the sample size, and the geographic
coverage. The Census Bureau carries out the survey research
for the AHS. Census designs the survey instrument, tests the questions, selects the sample of
individual housing units, sends out field representatives to conduct the survey, and
prepares the data for publication. Different from the AHS, the ACS is both sponsored
and administered by the Census Bureau. Census uses their expertise in Federal survey
research to develop the content and questions for the ACS, and to conduct the survey. Now, we’ll compare who gets interviewed
on each survey, and how often. Both the AHS and the ACS are household surveys—meaning households are picked at random to receive the survey. But, the two surveys differ in who is interviewed
and how often. First, the ACS happens every year, while the
AHS happens every two years. The AHS is longitudinal, meaning the same
housing units are visited every two or four years. The ACS is not. In fact, the AHS is one of the only longitudinal
housing surveys in the world—which makes it the best data source for users interested
in studying changes to the US housing stock over time. The previous AHS sample of housing units was
revisited every other year from 1985 to 2013. A new sample of housing units was selected
in 2015 and will be revisited every other year for years to come. Another key difference—the ACS includes
group quarters, such as dormitories. The AHS does not include group quarters. Finally, the AHS does not include any households
in Puerto Rico, where the Census Bureau conducts a version of the ACS for Puerto Rico, called
the Puerto Rico Community Survey. Let’s compare how long the surveys have
been conducted. The AHS has been around since 1973. The ACS has been conducted since 2001. Now, let’s look at each survey’s sample
design. For example, let’s compare how many households
participate in each survey. The AHS sample is much smaller than the ACS
sample—with about 83,000 completed interviews each survey year. The ACS sample is very large—with about
2.2 million completed interviews every year. For both surveys, the Census Bureau randomly
selects households to participate. But there are important differences in the
way Census selects which households to survey for each. Let’s take a closer look at how Census picks
who receives the AHS and the ACS. For the ACS, Census selects households in
every county throughout the US, including Alaska and Hawaii. Because of its small sample size, the AHS is not conducted in every county throughout
the US. In fact, the AHS is administered in only about
1,000 counties throughout the US. These 1,000 counties are selected to be representative
of all other counties. As the sponsor of the AHS, HUD is especially
interested in producing housing statistics for the largest cities in the US. To achieve that goal, the AHS sample includes
about 3,000 households in each of the 15 largest cities and 20 other large cities. Since the 2015 survey, the AHS sample has
featured two parts. Part one is an integrated national sample,
made up of a representative sample of the nation, representative oversamples of each
of the country’s 15 largest metropolitan areas, and a representative oversample of
HUD-assisted housing units. HUD and Census survey the entire integrated
National sample once every 2 years. Part two of the AHS sample features independent
metropolitan area samples chosen from America’s top 50 largest cities. Each survey year, on a rotating basis, HUD
and Census survey one-half of what we refer to as the “Next 20” group of metropolitan
areas—metropolitan areas ranging from 16th to 51st largest by population. That means, we survey each member of the Next
20 group of metropolitan areas once every 4 years. Now, let’s examine who selects the questions
asked in each survey. Since ACS is sponsored by Census, they are
responsible for selecting the questions in the survey. Generally speaking, the ACS questions change very little between surveys. Census is responsible for determining how
much the questions in the survey will change. As the sponsor of the AHS, HUD is responsible for selecting the questions in this survey. Groups of questions in the AHS are called
“modules” and there are two types of these modules. Core modules are questions that appear each
time the AHS is conducted. Rotating topical modules are questions about
special topics that appear in one survey year, and then are rotated out, perhaps to reappear
four or six years later. Users will find many similarities in the types
of questions asked in both the AHS and the ACS. For example, the AHS and the ACS include virtually
identical questions on basic housing topics, including:
Whether the unit is occupied or vacant, whether the unit is owned or rented, the type of structure,
such as a single-family home or an apartment unit, year structure built; and the number
of rooms and bedrooms The AHS and the ACS also include virtually
identical questions on: The type of fuel used for heating, utility
costs, the presence of a kitchen and kitchen appliances; and the presence of basic plumbing
features, such as toilets, sinks, a shower or tub, and hot and cold running water. Both surveys include the same kinds of questions
on home values and housing costs, including rent, or homeowner costs such as mortgage,
property taxes, and insurance. Both surveys also collect basic demographic
information about all the people who live in the selected housing unit, including:
Age, gender, race and ethnicity, and citizenship status. And, both surveys collect demographic information
such as: Educational attainment, marital status, disability
status, and year the householder moved into the housing unit. Both surveys include basic questions about
income and income sources. Both surveys also include basic questions about financial assistance such as Temporary
Assistance for Needy Families (or TANF) and Supplemental Nutritional Assistance Programs
(or SNAP), commonly referred to as “food stamps.” Now, let’s take a closer look at some of
the kinds of questions that are asked in the AHS that are not included in the ACS. Users will find many types of questions in
the AHS that are not asked in the ACS. For instance, the AHS includes more questions
about the housing structure, including: The size of the housing unit, the presence
of a garage, the type of heating and cooling system, and the presence of structural amenities
such as a porch and fireplace. The AHS also includes questions about appliances—such as washer, dryer, and dishwasher—that are not found in the ACS. The AHS takes a much deeper dive into housing
quality, including: The adequacy of plumbing, heating, and electricity,
deficiencies, such as signs of mice and cockroaches or cracks, holes, and broken plaster, toilet
breakdowns, and heating problems, including breakdowns and utility interruptions, inadequate
insulation, or the cost of heating. The AHS also delves into housing quality issues
like: Water leakage, external building conditions,
such as a sagging roof, broken windows, or a crumbling foundation, the presence of mold;
and sewage disposal breakdowns. Another key difference in the surveys—the
AHS takes a closer look at housing costs and affordability. It includes more questions about:
Mortgage information, remodeling costs and types of projects, and the cost of upkeep. Different from the ACS, the AHS also includes
questions about rental subsidies. The AHS also includes questions about neighborhood
quality, including the presence of: Bodies of water in the area, bars on windows,
vandalized or abandoned buildings, trash, litter, or junk on the streets, as well as,
opinions on schools, crime, bus, subway and commuter bus service, and the risk for disaster. Users will also find questions about reasons
for moving and the search for new housing in the AHS. For instance, the AHS collects data on the
type, tenure, and number of people living in the previous residence…as well as data
on how housing costs changed due to a move…and the reasons for leaving. The survey also looks at the search for housing—asking
questions about how movers found their new home and their satisfaction with their new
neighborhoods. There is one major difference between the
two surveys that is important to note. Each AHS contains special “rotating” topics
that appear in one survey and are replaced in the next survey. Commuting costs and modes…home accessibility…health
and safety characteristics…and emergency and disaster preparedness are some of the
recent topics. The AHS has also included topical modules
on: Delinquent payments and notices, evictions,
food security, housing counseling, and neighborhood arts and cultural resources. We’ve looked at the types of questions that
are unique to the AHS. Now, let’s take a look at the types of questions
that are asked in the ACS, but not in the AHS. The ACS includes a variety of questions that
are not found in the AHS. For example: The ACS includes questions about computer,
laptop, and tablet ownership, as well as questions about how households access the internet (cell
phone, DSL, cable modem). The survey includes a question about household automobile ownership, a question about ancestors
and ethnic origin, and a question about the type of bachelor’s degree (if applicable). The ACS contains a question about the type of health insurance as well as questions about
VA service-connected disability status and rating. The ACS includes a question about commuting methods and the journey to work, The survey also asks questions about the numbers
of hours worked and the type of work performed, along with questions about profession. Another helpful way to compare the AHS and
the ACS is by the types of data products that are available to help you access the results
and use the data in your work. Let’s compare the two surveys. The ACS and AHS both have webpages on census.gov,
with a wealth of information about each survey. Summary table estimates and microdata are
the two main data products for both surveys. Both surveys have summary data tools to help you access your summary tables quickly and
easily. For example, the AHS Table Creator is a user-friendly
web application that gives you access to tens of thousands of pre-calculated tables that
you can download in HTML or Excel format—without statistical software. Similarly, the ACS provides easy access to
a wide variety of data estimates via American FactFinder. More experienced data users can access either
survey’s public use microdata files—files containing the individual-level responses
to the survey questions. In the AHS, microdata files are known as Public
Use Files—or PUF files. The ACS refers to its microdata as PUMS, or
the Public Use Microdata Sample. The AHS PUF microdata includes all housing
units that were interviewed, while the ACS PUMS includes only a sample of the housing
units that were interviewed. Both the PUF and the PUMS have limited geographic
indicators available. The AHS PUF includes Census Division and Metro
Area Name for the nation’s large metro areas. The PUMS contains States and PUMA’s, which
are areas of 100,000 persons or more. Both surveys have resources on their websites
to help you use the public use microdata. The AHS Codebook has information about each variable’s basic description, availability,
question text, answers, and other notes. The mini codebook is a list of AHS variables, their descriptions, and whether they are included
in the public use files. It can help you find the exact variable names
as they appear on the PUF and codebook. A link to the mini codebook is located on
the lower left corner of the AHS codebook webpage. Similarly, the ACS has a data dictionary with information about each variable. You can find it in the technical documentation
section of the ACS website. Both surveys have public use file users guides. Getting Started With the Public Use File:
2015 and Beyond provides a user-friendly introduction to the 2015 and 2017 AHS PUF microdata. This free Getting Started Guide explains important
differences between the 2015 and 2017 PUFs relative to prior-year PUFs. You can download the Guide from the technical
documentation section on the American Housing Survey website. The handbook—What Public Use Microdata Sample
Data Users Need to Know—gives ACS users valuable information on how to access the
microdata and produce their own tables. You can download this guide from the publications
section of the Census website. And, both surveys provide Estimates for User
Verification, which are sets of summary estimates to help microdata data users verify they are
using the microdata correctly. Finally, we’ll look at how the surveys compare
when it comes to estimates for small areas, such as towns or Census tracts. The sample for the AHS consists of over 100,000
housing units, but only about 83,000 households complete an AHS interview. This is enough data to create statistics that
represent: The nation as a whole, the region (Northeast,
Midwest, South and West), select states, the nine census divisions, the top 15 largest
metro areas, and 20 rotating metro areas The AHS does not have a large enough sample to generate statistics specific to smaller
areas such as cities, towns, or Census tracts. The AHS is not the right data source for users
interested in studying or comparing counties or other smaller areas. On the other hand, few surveys have a sample
as large as the ACS. Every year it collects data from more than
2 million households. With such a large sample, the ACS can be used
to creates annual statistics for: The nation as a whole, each of the 50 us states,
as well as counties, cities, and other areas with populations of 20,000 or more. It is important to note that the Census Bureau also produces estimates for areas with populations less than 20,000. Census does this by combining 5 years of ACS data. Since the AHS is longitudinal—surveying
the same housing units—it cannot combine samples like the ACS. If you are interested in studying or comparing
areas with smaller populations, the ACS is an excellent data source to meet your needs. On behalf of the Department of Housing and
Urban Development and the U.S. Census Bureau, we would like to thank you so much for joining
us for today’s presentation on how the American Housing Survey differs from the American Community
Survey. We hope this information has been helpful
in deciding which survey is best suited to answer your data questions. It’s just one of the ways we’re working
to make it as easy as possible for you to use HUD and Census housing data in your work.

Danny Hutson

Leave a Reply

Your email address will not be published. Required fields are marked *