assessing the transportation needs of welfare-to-work participants in ...

Another limitation introduced by the use of supplemental information was that the GEARS
database did not provide a case name. The case name used for surveys was derived from the
FOCUS database maintained by DPSS, which indicates the official person designated to conduct
the business of the welfare case with DPSS. The case name used for surveying purposes was
derived from a different source than the case phone numbers. Therefore, some sampled cases
with phone numbers did not have a case name and vise versa. Another issue regarding case
names involved the disproportionate presence of female case names, even for two-parent (U)
cases in which a male is usually present in the household. Therefore, when interviewers were
contacting two-parent (U) families, they were disproportionately surveying the woman
associated with the case. Although the oldest person on cases sampled was approximately 15%
male (based on FOCUS data), the initial male response rate was considerably lower.
Adjustments were made to the surveying process to compensate for this limitation (described in
the “Survey Implementation” section below).
To respond to the low male response rate introduced by the fact that case names are
disproportionately female, 100 supplemental interviews of two-parent (U aid type) cases were
conducted to increase the male response rate. The UCLA Lewis Center sampled additional cases
and funded the supplemental interviews, which targeted two-parent (U) cases because males are
most prevalent in this type of welfare case. The process of sampling additional two-parent (U)
cases for these interviews resulted in an overall CTNA sample that contains a disproportionately
large number of two-parent (U) cases (described in more detail below). Also, the sample drawn
for these additional 100 supplemental interviews were not geocoded and assigned a supervisorial
district since the first wave of 1545 interview adequately represented all districts.
Description of Stratified Random Sample
The following describes the randomly sampled GAIN cases with regard to the data limitations
described above:
Initial random sample: 19,996 (100%)
Cases with addresses: 15,595 (78%)
Estimated cases with valid residential phone number: 12,629 (63%)
Total completed surveys: 1,645 (8%)
Despite the limitations in data and contact information described above, the overall randomness
of the sample and survey were preserved. As shown in Table 1, the composition of the sample
population and final survey respondents is representative of the entire GAIN population. There
are slight differences, primarily in terms of household aid type and case primary language, which
can largely be attributed to the over-sampling of two-parent (U) cases to increase the male
response rate. The over-sampling of two-parent cases may also explain the observed differences
in primary language. Non-English cases are more prevalent among two-parent (U) cases. Since
U cases are over-represented among survey respondents, survey tabulations for this report are
weighted in order to assure that that tabulations are representative of the welfare to work
population in Los Angeles County (as described in more detail below).
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