Current Population Survey Design and Methodology - Census Bureau

espondents, obtaining answers to only a couple of critical
questions. Another change in the data collection procedures
was an increased reliance on using centralized telephone
interviewing. Households not interviewed by the
computer-assisted telephone interviewing (CATI) centers
are recycled back to the field representatives continuously
during the survey week. However, cases recycled late in
the survey week (some reach the field as late as Friday
morning) can present difficulties for the field representatives
because there are only a few days left to make contact
before the end of the interviewing period.
As depicted in Figure 16-2, there has been greater variability
in the monthly Type A nonresponse rates in CPS since
the transition in January 1994. The annual overall Type A
rate, the refusal rate, and noncontact rate (which includes
temporarily absent households and other noncontacts) are
shown in Table 16−1 for the period 1993−1996 and 2003.
Table 16−1. Components of Type A Nonresponse Rates,
Annual Averages for 1993−1996 and 2003,
National Estimates
[Percent distribution]
Nonresponse rate 1993 1994 1995 1996 2003
Overall Type A ......... 4.69 6.19 6.86 6.63 7.25
Noncontact ............ 1.77 2.30 2.41 2.28 2.58
Refusal ................ 2.85 3.54 3.89 4.09 4.10
Other .................. .13 .32 .34 .25 .57
Panel nonresponse. Households are selected into the
CPS sample for a total of 8 months in a 4-8-4 pattern as
described in Chapter 3. Many families in these households
may not be in the CPS the entire 8 months because of
moving (movers are not followed, but the new household
members are interviewed). Those who live in the same
household during the entire time they are in the CPS
sample may not agree to be interviewed each month.
Table 16−2 shows the percentage of households who were
interviewed 0, 1, 2, …, 8 times during the 8 months that
they were eligible for interview during the period January
1994 to October 1995. These households represent seven
rotation groups (see Chapter 3) that completed all of their
rotations in the sample during this period. The vast majority
of households, about 82 percent, completed interviews
each month, and only 2 percent never participated (for further
information, see Harris-Kojetin and Tucker, 1997).
Dixon (2000) compared those who moved out to those
who moved in. Out-movers were more likely to be unemployed
but more likely to respond compared with
in-movers. Unemployment may be slightly underestimated
due to the combination of these two effects.
Effect of Type A Noninterviews on Labor Force
Classification.
Although the CPS has monthly measures of Type A nonresponse,
the total effect of nonresponse on labor force estimates
produced from the CPS cannot be calculated from
Table 16–2. Percentage of Households by Number of
Completed Interviews During the 8 Months
in the Sample, National Estimates 1
[January 1994−October 1995]
Number of
completed interviews
Percent
1994−1995
0 .............................................. 2.0
1 .............................................. 0.5
2 .............................................. 0.5
3 .............................................. 0.6
4 .............................................. 2.0
5 .............................................. 1.2
6 .............................................. 2.5
7 .............................................. 8.9
8 .............................................. 82.0
1 Includes only households in the sample all 8 months with only
interviewed and Type A nonresponse interview status for all 8 months,
i.e., households that were out of scope (e.g., vacant) for any month
they were in the sample were not included in these tabulations. Movers
were not included in this tabulation.
CPS data alone. It is the nature of nonresponse that we do
not know what we would like to know from the nonrespondents,
and therefore, the actual degree of bias
because of nonresponse is unknown. Nonetheless,
because the CPS is a panel survey, information is often
available at some point in time from households that were
nonrespondents at another point. Some assessment can
be made of the effect of nonresponse on labor force classification
by using data from adjacent months and examining
the month-to-month flows of people from labor force
categories to nonresponse as well as from nonresponse to
labor force categories. Comparisons can then be made for
labor force status between households that responded
both months and households that responded one month
but failed to respond in the other month. However, the
labor force status of people in households that were nonrespondents
for both months is unknown.
Monthly labor force data were used for each consecutive
pair of months for January through June 1997, for households
whose members responded for each consecutive
pair of months and separately for households whose
respondents responded only one month and were nonrespondents
the other month (see Tucker and Harris-Kojetin,
1997). The top half of Table 16−3 shows the labor force
classification in the first month for people in households
who were respondents the second month compared with
people who were in households that were noninterviews
the second month. People from households that became
nonrespondents had higher rates of participation in the
labor force, employment, and unemployment than those
from households that responded in both months. The bottom
half of Table 16−3 shows the labor force classification
for the second month for people in households that were
respondents in the previous month compared with people
who were in households that were noninterviews the previous
month. The pattern of differences is similar, but the
magnitude of the differences is less. Because the overall
16–4 Quality Indicators of Nonsampling Errors Current Population Survey TP66
U.S. Bureau of Labor Statistics and U.S. Census Bureau