Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter.
Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.
OCR for page 23
3
Sampling Frames
Graham Kalton, moderator for the session, described the presentations
as a discussion of the potential uses of sampling frames to aid in particular
surveys and the multiple sources for these frames. Given the costs associated
with frame development, some of the questions to consider are whether there
are any economies that can be achieved with the current sampling frames and
what are the difficulties related to implementing them.
USING LARGE SURVEYS TO ASSIST IN FRAME
DEVELOPMENT FOR SMALLER SURVEYS
James Lepkowski (University of Michigan) began his talk on using large
surveys as frames for smaller surveys with examples of cases in which this
is currently being done and a discussion of the issues associated with these
approaches. The first example described the Current Population Survey (CPS)
and the American Time Use Survey (ATUS).
The CPS is a well-established, rotating panel, continuous survey of the
noninstitutionalized population in the United States ages 15 and older. A joint
effort of the Census Bureau and the Bureau of Labor Statistics, the CPS is the
primary source of information about characteristics of the U.S. labor force.
It uses independent samples in each state and the District of Columbia and
oversamples the Hispanic population. Since the 1940s, it has used probability
sampling and has produced national as well as state-level estimates.
The ATUS uses a sample of households from a CPS panel that is rotating
out of the survey. There are three stages of the ATUS sample design. From
23
OCR for page 24
24 THE FUTURE OF FEDERAL HOUSEHOLD SURVEYS
the sample of households (in the third and final stage of the sample design),
one person age 15 or older is randomly selected for interview by telephone
and becomes the ATUS “designated person.” Nontelephone households are
contacted by mail, given a phone number, and requested to call in, with a $40
incentive that is awarded at the completion of the survey.
Lepkowski said that one of the major challenges in using the CPS as a
frame for the ATUS is timing. Although most of the CPS sample becomes avail-
able to the ATUS within three months, the sample is still spread out over time
due to the interviewing and processing schedule. Similar challenges related to
timing have led some survey organizations to abandon second-phase samples.
Another challenge in the context of the CPS and the ATUS is that the
CPS is a household survey, which must then be transformed into a person-
level sample for the ATUS. Finally, it is possible that ATUS response rates are
adversely affected by previous participation in several prior CPS interviews, but
it is difficult to determine conclusively the potential magnitude of this effect.
Overall, the telephone response rates are in the mid-50 percent range.
The second example Lepkowski described is the case of the National
Health Interview Survey (NHIS) and the Medical Expenditure Panel Survey
(MEPS). The NHIS is the primary source of data about the U.S. household
population’s health and health care utilization. The survey is conducted by
the Census Bureau and sponsored by the National Center for Health Statistics
(NCHS), although other agencies also fund supplements, a situation that can
be an important factor that influences an organization’s ability to share sample
efficiently. The NHIS is a continuous, multistage, national probability survey
with oversamples of black, Hispanic, and Asian populations. Response rates
vary depending on the type of interview, generally ranging between 65 and 80
percent.
The MEPS, sponsored by the Agency for Healthcare Research and Qual -
ity (AHRQ), uses completed NHIS interviews as a sampling frame for the
household component of the survey (there is also a medical provider com -
ponent and an insurance component). The goal of the survey is to produce
national and regional estimates of health care utilization and expenditures.
Approximately 15,000 households are included annually, with occasional
oversamples for additional policy-relevant subgroups. The MEPS also utilizes
the oversampling performed for the NHIS. Rather than a cross-sectional
design like the NHIS, the MEPS uses a panel design.
The MEPS response rates are also affected by the response rates to the
NHIS. Response rates for recent NHIS surveys have typically been in the
upper 80s, and the MEPS nonresponse rate is compounded by the nonresponse
in the first phase. In addition, the NHIS sample sizes can vary from year to year,
changing the proportion of the sample the MEPS takes from the NHIS to meet
its own sample size designations.
One of the main advantages of using one survey as the sampling frame
OCR for page 25
25
SAMPLING FRAMES
for another is the cost efficiency that can be achieved by the second survey.
The cost savings can be realized in the form of efficiencies in sample design,
data collection, screening, and data processing. For example, the ATUS has
a list of items that are nearly identical to those in the CPS, and going through
the same processing system saves the cost of system development. Although
typically the efficiencies benefit the second survey, Lepkowski observed that
when the sample sharing is a long-term arrangement, there has to be some
sharing of the cost burden as well.
He pointed it out that there are several challenges related to these designs
as well. Nonresponse rates can be affected not only by the fact that respondents’
willingness to participate sometimes declines by the time of the second-phase
survey, but also because of increased difficulties related to locating sample
persons by the time of the follow-up. Although drawing a sample based on
another survey also presents a unique opportunity to estimate nonresponse bias
based on responses to the first survey, this is often leveraged to some extent, but
perhaps not as much as it could be. A related concern is the measurement bias
that can potentially be introduced into the second-phase survey as a result of
participation in previous surveys, even if respondents are willing to participate
(also known as time-in-panel bias).
The quality of any stratification performed for the second-phase survey
depends on the quality of the data collected in the first survey. For example,
if the second-phase survey is stratified on income and this information is mis -
reported in the first survey, the misclassification will lead to inefficiencies in
selection.
Capacity issues are often another consideration. The first survey has to
provide adequate sample to meet the needs of the second-phase survey. Some
of this is driven by disproportionate allocation in the second phase, which may
use up a large proportion of a particular subgroup, which can also preclude
the first-phase sample’s use by other surveys. Small-area estimation is another
hurdle for second-phase samples.
All of these factors lead to a set of administrative challenges that have
been briefly mentioned in the context of the examples provided but are worth
acknowledging more generally, Lepkowski said. One such challenge involves
funding, particularly deciding on how the second-phase survey can share some
of the costs of the first-phase survey (e.g., the costs related to screening or list -
ing). Another challenge is related to the changes in sample size and the logistics
associated with adapting to these changes. Second-phase surveys tend to be
administered after the first survey, although concurrent designs are also pos -
sible, and these represent a separate set of administrative challenges. The use
of some sample frames, such as the Master Address File (MAF), has limitations
that impose restrictions on second-phase survey operations.
Something that is not typical of currently existing two-phase surveys is
a conscious effort to design them as true two-phase surveys from the outset.
OCR for page 26
26 THE FUTURE OF FEDERAL HOUSEHOLD SURVEYS
Instead, second-phase surveys seem to occur on the basis of arising opportuni -
ties for collaboration between agencies and an after-the-fact recognition that
there is a possibility to save on costs across two or more organizations.
A joint design from the outset would allow for optimal allocation across
phases and better input into units of selection. Two-phase surveys could
also be more successful at reducing nonresponse if the goals and designs
of both surveys were kept in mind. This would allow for the planning of a
more comprehensive incentive structure, as well as tracking and follow-up
procedures. There is also tremendous opportunity to use paradata and a
responsive design for utilizing first-phase data to predict what will happen in
the second phase. Prediction models compared with what actually transpired
in the second phase can then be used, improving the ability to intervene and
improve response properties.
THE POTENTIAL ROLE OF THE AMERICAN COMMUNITY
SURVEY IN SAMPLING RARE POPULATIONS
Keith Rust (Westat) began by saying that he added the word “potential”
to the title of his presentation to illustrate that some of the ideas presented are
in development or are under consideration, rather than already in progress. He
then proceeded with an overview of the American Community Survey (ACS).
Conducted by the Census Bureau, the ACS surveys approximately 250,000
households each month by mail, or 3 million households per year. The ques-
tionnaire contains 48 questions about each individual in the household and 21
questions on housing. Nonrespondents to the mailed questionnaire receive a
telephone follow-up whenever possible (when a phone number is available).
The remaining nonrespondents for whom there is no phone number or who
did not respond by phone are eligible to be in the sample for follow-up by
an in-person interview using computer-assisted personal interviewing (CAPI)
technology. The in-person follow-up obtains interviews from about one-third
of the 48 percent of nonrespondents who do not respond by mail or telephone.
But the CAPI subsample rate does vary by population group.
The overall weighted response rate to the ACS is very high at 97-98 per-
cent, but due to CAPI subsampling for follow-up, the data actually obtained
are about two-thirds of the original sample. Therefore, data are obtained for
approximately 2 million households per year. Differential sampling also affects
the total final count of respondents. The sampling for the ACS is complex,
but, as an example, there is an initial oversample of small governmental units.
This works out to about 15 percent of the sample, which covers 5 percent
of the population in these units. Also, since nonresponse CAPI subsampling
yields about one-quarter of the sample that is obtained through CAPI, these
interviews get three times the weight of the remainder. This suggests that the
effective sample size due to the differential weighting is closer to 1.5 million
OCR for page 27
27
SAMPLING FRAMES
household interviews per year, although the design effects due to weighting
could vary among subgroups.
As with any survey collected by mail, there is item nonresponse. There are
a lot of questions on the ACS, and some of them are open-ended responses
that must be coded (e.g., industry, occupation, field of degree). There is also
the issue of response error, particularly when it comes to reporting income.
Some questions involve a challenging recall task, such as the question about
employment. Each of these factors can contribute to item nonresponse and
response error.
It is in this context that the use of the ACS as a frame for sampling rare
populations should be considered, Rust said. Issues to keep in mind with sam-
pling rare populations are cost and burden of sampling, timeliness of the data
available, the sample size available, the amount of cumulation that is needed
(from the ACS), the effects of differential weighting, coverage issues, response
error, the quality of the contact information, sampling error estimation, and
confidentiality and human subjects concerns.
One of the most obvious benefits to using the ACS as a frame for other
surveys is the reduction in the cost and burden associated with smaller surveys.
Cost is reduced for the smaller survey by not having to screen a large initial
sample in order to identify a subpopulation of interest. Respondent burden is
reduced by not having to participate in a screening survey. Furthermore, there
is the ability to fine-tune sample allocation for different population subgroups.
Sample size can also be controlled precisely because the sampling done is
from a frame of people known to be in the population of interest. Finally, it is
possible to orchestrate the release of sample in waves or replicates in order to
fine-tune yield.
As Lepkowski mentioned in the previous presentation, the timeliness of
data available for use as another survey’s sampling frame is also a consideration,
Rust said. In this case, what proportion of people will have a status change
that might cause them to move into or out of the population of interest? As an
extreme example, the ACS would be of no use as a frame in the case of new -
borns, very recent immigrants, or the recently unemployed. Another question is
what constitutes a sufficient sample for the rarest group of interest. If cumula -
tion of data over many months or years is required, then issues of timeliness are
exacerbated. Furthermore, the differential representation in the ACS sample
may lead to large weighting design effects in a rare population, although some
of this may be offset with subsampling—if there is enough sample to do this.
Like most surveys, the ACS probably undercovers certain groups (potentially
the groups of interest) in the population. Data from the census undercover new-
borns; it is likely that the ACS does as well. Household surveys tend to under-
cover young adult black men, so it seems likely that the ACS would, too. The
ACS weighting adjustments can help address undercoverage for estimates, but
it is unknown how useful this will be for the subsampled rare population group.
OCR for page 28
28 THE FUTURE OF FEDERAL HOUSEHOLD SURVEYS
Misclassification as it relates to rare population status can result in substan-
tial undercoverage and wasted sample, Rust went on. Any survey of a rare pop-
ulation that uses screener identification will have this problem. Furthermore,
in the case of the ACS, which is largely a mail survey, there is no interviewer
who can follow up with probes to ascertain that a respondent is answering a
particular question correctly.
The quality of the contact information that is available on the ACS is
another issue to consider, Rust observed. Is the address information on the
ACS accurate enough for follow-up by mail, telephone, or in-person contact?
The ACS does not ask for address corrections or clarifications on its form. This
could be a potentially significant issue, particularly for multiunit structures,
he said. If the contact information is sufficient for a subsample, there is the
related issue of confidentiality and human subjects protection issues. The ACS
response is required by law; respondents are told that their responses are confi -
dential and will be used for statistical purposes only. Title 13 of the U.S. Code,
which authorizes collection of personally identifiable information, requires that
follow-up surveys must be conducted by the Census Bureau because the infor-
mation collected in the ACS is confidential. Thus, access to this information
cannot be shared outside the agency.
The ACS sample is a rolling sample, with a new sample produced every
month. Could this be utilized to design rolling samples for rare populations? It
may be possible to draw sample from the ACS every quarter, but, for reporting
subgroups, data can be cumulated across quarters to get a continuous rolling
sample. This could be used to measure trends, Rust said.
Another question that arises is whether the ACS in its own right is suf -
ficient to identify a rare population of interest. This suggests the possibility
of adding questions to the ACS to be used as a screener for identifying a rare
population. This leads further to what kind and how many questions can be
asked, as well as who is responsible for the quality of the data from these ques -
tions. He said it is important to distinguish screener questions from those that
will be tabulated along with other ACS data. How will the effect of adding
questions to the ACS on response rates be evaluated? He observed that this
may not be the right time to add questions, given suggestions that the ACS
should be cancelled altogether, or at least made voluntary, because of claims
that the survey is too intrusive.
Rust noted that a couple of examples can be used as case studies of
smaller surveys using the ACS for sample creation. One is the National
Science Foundation’s National Survey of College Graduates (NSCG). This
survey, conducted by the Census Bureau in the past, measures the number
and characteristics of people with science and engineering degrees. Formerly
the frame for the NSCG was the census long-form sample. Since the long-
form sample no longer exists, the ACS will be used as a frame instead. A
“field-of-degree” question was added to the ACS specifically for that purpose
OCR for page 29
29
SAMPLING FRAMES
(although it is also of interest in its own right). The benefit of adding the ques -
tion is that it permits oversampling of people with science and engineering
degrees. However, several years of ACS data will be required to achieve what
has previously been the desired sample for some of the groups. Still, this is a
vital question for targeting the sample of persons with science and engineer-
ing degrees, and getting that information from the ACS greatly decreases
screening costs. The field-of-degree question does have its problems, he said;
it is an open-ended question and therefore requires extensive coding. And in
2009 there was 9 percent item nonresponse. There are most likely issues of
data quality and coverage. And this also raises the question of whether the
NSCG could benefit from using a rolling sample, at least for a component.
The second case study describes a test of the feasibility of using the ACS
for the National Immunization Survey (NIS). The NIS produces annual vacci -
nation rates for children ages 19 to 35 months, plus a component for teenagers
ages 13-17 years. It produces data at multiple levels of geography, including
78 areas known as Immunization Action Plan Areas. The NIS currently uses
a list-assisted random digit dialing (RDD) sample—a methodology with high
screening costs, because only 5 percent of households have infants. And the
sample size is quite large: 26,000 infants per year and 31,000 teens.
Rust observed that this survey, like others, experiences many of the prob-
lems associated with telephone surveys: low response rates and undercoverage,
to name just two. To help combat these problems, the proposal was to consider
using the ACS as a frame for the NIS. The ACS certainly offers the possibility to
overcome many of the current deficiencies in the NIS sample, and the idea of a
rolling sample would integrate naturally into the NIS design. There are also rich
data on respondents that could be used for adjustment and bias analyses. The
ACS probably undercovers persons under 1 year of age, so there are probably
coverage problems. The immunization surveys are interested in children ages 19
months and older, but because of the time lag, those under 1 year of age would
need to be selected from the ACS. Moreover, the NIS would need to be in the
field within 19 months of the ACS response to cover 19-month-olds.
The Census Bureau and the Centers for Disease Control and Prevention
jointly conducted a one-state trial with children ages 19-35 months using ACS
data for the period 2006-2008. They found that although the response rate
was good, in-person interviewing was vital. A provider check was included in
the survey, in which respondents gave contact information for those who pro-
vided the immunization. Generally, respondents gave good information about
the provider, but confidentiality issues were raised related to the fact that the
respondents were identified on the basis of the ACS. As a work-around, Rust
said, providers were given special sworn status by the Census Bureau. Although
this appeared to work for the trial, it may be an issue for surveys that want to
use the ACS as a frame.
The ACS has the potential to greatly reduce screening costs and reduce
OCR for page 30
30 THE FUTURE OF FEDERAL HOUSEHOLD SURVEYS
undercoverage for surveys of special populations. It is also rich in respondent
information, which is quite useful for enhancing estimation. These benefits
may be overstated, however, as the evidence suggests that a significant amount
of in-person interviewing will be needed. Other issues include timing, cover-
age, data quality, sample size, and differential weighting. Using the ACS data
as the basis for a person’s inclusion in a future survey raises issues of consent
and confidentiality. Issues related to including additional questions on the ACS
(such as how many additional questions and who decides on the questions) are
other hurdles that any survey using the ACS as a frame must overcome. Given
current Title 13 restrictions, the Census Bureau must conduct the survey and
maintain the data. Rust ended by saying that, although the ACS appears to offer
opportunities for use as a sampling frame for other surveys, it is not a panacea,
and there are real risks of abuse.
SAMPLING FRAMES FOR FEDERAL HOUSEHOLD
SURVEYS: A VISION FOR THE FUTURE
Frederick Scheuren (National Opinion Research Center) began his talk on
sampling frames by saying that the goal of the workshop should be to identify
ways of supporting an information society, not just individual agency missions.
The focus should be on multimode and multiagency sampling frames. He noted
that even the concept of “household” survey frames is too narrow and unable
to describe many new developments, such as the spread of cell phones.
Scheuren said that government agencies do not typically cooperate well,
except in times of crises. But there are some common challenges across the
federal statistical system that need to be addressed: survey costs are too high
and the delivery of information is too slow. Referring back to the presentation
by Rust, he gave the example of outdated sampling frames that can be so old
by the time they are shared with another agency that they are no longer useful.
Scheuren argued that government data collections will become increasingly
difficult to conduct in a data-rich world, with information becoming available
from many competing data sources. This means that government agencies will
have to learn to adapt or they will risk irrelevance. Some of the examples from
other countries discussed earlier are cheaper, faster, and more responsive, and
they should not be ignored, he said, even if the same approaches cannot be
implemented in the United States.
A possible new paradigm in a data-rich world could be characterized by
emphasis on paradata, both design and model-based estimation, and quick,
simulated outcomes, instead of traditional estimators. Statistical systems can no
longer afford large samples, so small sample properties also have to be stressed
in this context.
Unified sampling frames are an important consideration for the future. These
could be assembled starting with geographic addresses, which would then be
OCR for page 31
31
SAMPLING FRAMES
linked to sampling frames based on other modes of contact, such as telephone
(both landline and cell phone) and web. An ideal unified sampling frame would
also integrate information available from such sources as the census, the Ameri-
can Community Survey, the Internal Revenue Service, the Social Security Admin-
istration, and the U.S. Postal Service. The key benefit to adding the administrative
data is that they enable stratification of the sample on variables of interest.
Scheuren argued that cooperation related to work on sampling frames is
important, and that in his view all federal survey contracts should require data
sharing for frame construction. He acknowledged that there are many barriers
to implementing this type of mandatory data sharing, including legislative and
regulatory restrictions, the lack of political and bureaucratic will, the fact that
it violates precedents, and the need for a long-term commitment. Confidential -
ity concerns could be addressed if access is through a data enclave—in other
words, a secure environment that provides authorized researchers access to
confidential microdata. Access would have to be limited in purpose to frame
construction only and subject to oversight by a neutral entity, such as the Office
of Management and Budget.
Given the large opportunity costs, it is important to consider whether
implementing a unified sampling frame is worth it, said Scheuren. Such a
system could improve data quality and enable faster delivery times. However,
maintaining the frame will be expensive, and depositing the data in the enclave
will take time, which means that at least some of the information will be out -
dated. He noted that although an obvious benefit of the work on a unified
sampling frame would be the development of a cooperative structure in the
federal statistical system, a large investment in sampling frames could turn out
not to be the right long-term investment.
Scheuren reiterated that the world is becoming more data dense, and gov -
ernment statistical agencies now have strong competitors. This could mean that,
in the future, surveys and censuses will have a smaller role, and emphasis will
shift to increasing reliance on administrative data and to combining informa -
tion, which is more than just combining data. The federal statistical system will
be ready for this new reality if agencies invest in becoming more cooperative.
DISCUSSION
Frauke Kreuter (University of Maryland) asked whether Rust had a sense of
what the cost savings would be for the NIS if it were to use the ACS as a sam -
pling frame. Rust responded that although he did not know, he did not think
cost savings were a particular consideration; this initiative was probably driven
by quality concerns and dissatisfaction with how the survey is conducted now.
Marcie Cynamon (National Center for Health Statistics) added that there were
concerns about the NIS coverage related to the percentage of the children who
were in the age range through the RDD and cell phone components.
OCR for page 32
32 THE FUTURE OF FEDERAL HOUSEHOLD SURVEYS
Related to the ACS as a frame for the NSCG, Robert Kominski suggested
that the argument for including a screener question on the ACS for the NSCG
was the cost savings of $3 to $6 million. There was a good chance that, in many
cases, the addresses in the NSCG frame were no longer applicable for persons
who held at least a bachelor’s degree. However, even with the delay in ACS
processing, the data would still be more current than alternatives. In addition,
getting data more frequently makes the sample to draw from much larger, even
though the sampling rate is much smaller.
Cynamon noted that the National Health Interview Survey gives half of its
sample to the MEPS, and it is not a cherry-picked half. Trena Ezzati-Rice (Agency
for Healthcare Research and Quality) discussed the screening efficiencies that
are gained from the integration of the NHIS and the MEPS. The integration has
been extremely helpful in the benchmarking of the survey estimates, she said, and
this has been useful for both surveys. The end result of the NHIS-MEPS integra-
tion is a very rich frame of auxiliary variables that can be used for nonresponse
adjustments. Further research has found that incorporation of some of the health
variables from the NHIS reduces bias in the MEPS estimates.
Lepkowski added that, if there is this rich set of data and methods for
doing model-based estimates on something like the MEPS and the extension
of the frame to the other half of the NHIS sample, then why are the only esti -
mates produced based on the MEPS sample? The estimates could be of higher
precision, but currently these resources are not being utilized, which is part of
the failure of two-phase designs.
Sondik added that, beyond the use of a survey as a sampling frame for
another survey, the potential is also there for using substantive data from the
first survey, although implementing this link would require substantial resources.
Ezzati-Rice commented that the integration of the NHIS and the MEPS has
provided an additional data point—beyond the two years of the MEPS data—for
longitudinal analysis. There has not been as much mining of these data as there
perhaps could be, but they have been looked at, specifically the transitions in
health insurance coverage from the NHIS to the two panels of the MEPS. There
is also an interagency agreement to look at cancer survivors from the NHIS
supplement and then to look at issues related to health care access and costs for
these respondents in the MEPS.
On recycling sample, Kominski said that currently an ACS case can be
used in only one secondary survey based on the primary survey, but this is
not necessarily the case in the commercial sector, and other scenarios could
be considered. A participant from the National Agricultural Statistics Service
added that they have this problem with the Agricultural Resource Management
Survey: first, there is a screening survey, and then another survey uses up the
data, so they cannot be used for the next survey. A used case is taken from the
frame, and the weight of everything else is increased proportionally. The ATUS
adjusts its weights similarly.
OCR for page 33
33
SAMPLING FRAMES
Another speaker commented on the importance of developing a process
of selection for who gets to use what portion of a sample. What are the terms
of the agreement? And how does this get resolved?
Citro said that the ACS has the benefit of containing questions that can
be used for screening and weighting, but the available sample is limited. The
MAF does not contain survey responses, but the efficiencies associated with
sharing it would be a major step forward for the statistical system. She added
that although the sharing of the MAF is limited by Title 13 of the U.S. Code,
it is conceivable to think of enabling the sharing of some version of the MAF.
For example, one of the concerns is that, as part of its work, the Census Bureau
discovers sensitive information, such as a building that contains more housing
units than it is supposed to. However, this type of data could be collapsed
across cases. Under the Confidential Information Protection and Statistical
Efficiency Act (CIPSEA), a “slightly sanitized” version of the MAF could be
entrusted to the statistical system as a whole, and federal agencies could col -
laborate, perhaps in the context of a data enclave, on building, validating, and
using the MAF for sampling frames. As part of the data enclave, access could
potentially be also extended to data collection contractors who work on federal
surveys.
Kalton commented that the opportunity costs associated with Scheuren’s
vision are high, and the approach described by Citro is more manageable. It is
not only the statistical system that could benefit from access to the MAF, but the
MAF would also benefit from more agencies working on improving its quality.
Sondik asked Scheuren about his vision for the federal statistical system
and the idea of increasingly fuzzier data and methods: How will it be decided
what constitutes a benchmark? Scheuren responded that it is critical to take
advantage of opportunities that are already available: administrative records,
business frames, modern methods, sharing mechanisms, and the knowledge of
those who move around and have worked in other countries—especially smaller
ones forced to use more economical means to obtain data. Finally, he said, the
cooperation and common culture that existed in the Census Bureau and unified
the system in the 1940s and 1950s could be resurrected.
OCR for page 34
