East Bay Jewish Community Study - Jewish Federation of the ...

method for introducing cell phone sample into the methodology. Despite the known biases, we
had hoped that this sampling method would still help us reach younger Jews. Unfortunately,
respondents reached using the listed cell phone sample tended to be older than those reached
through the RDD landline sample.
The listed cell phone sample primarily was directed at the regions from which we would have a
very limited number of interviews if the regions were dialed proportionally. In other words, we
used the listed sample to increase the total number of completed interviews in the regions and
counties (Napa and Solano) that have a low incidence of Jewish households and would
otherwise have too few interviews for analysis.
The response rate for this portion of the sample was 2.2 percent overall, meaning 2.2 percent of
numbers dialed completed the entire screening portion of the survey. Approximately 29.3
percent of households reached using the listed cell phone sample were Jewish households
using the definition outlined previously.
3) Listed Landline Sample. The listed landline sample came from the same consumer list
vendor as the listed cell sample, Info USA Corp. The total list contained 3,832 records for the
greater East Bay region that had been deemed likely to be Jewish by the vendor. Similar to the
listed cell phone sample, the listed landline phone sample was directed primarily at the regions
with smaller Jewish populations.
The response rate for this portion of the sample was 3.7 percent overall, meaning 3.7 percent of
numbers dialed completed the entire screening portion of the survey. Approximately 40 percent
of households reached using the listed landline phone sample were Jewish households using
the definition outlined previously.
Dialing Procedures
Professional telephone interviewers conducted all the interviews using a CATI-based
interviewing system. The CATI programming was tested extensively to ensure accuracy before
interviewing began and monitored during fielding for quality control.
To achieve 820 completed interviews, we dialed a total of 502,014 individual phone numbers
and placed 347,838 calls. Working phone numbers (i.e. excluding businesses, disconnects,
etc) were dialed up to ten times. In between calls, phone numbers were shelved for at least
three hours in between attempts. That means that a single phone could not be attempted more
than twice in one evening.
Dialing took place between the hours of 5pm to 9pm in California on Monday through Thursday,
and 2pm to 9pm on Sundays. No dialing attempts were made on Friday evening or on
Saturdays.
The screener questions averaged approximately 2.6 minutes. The full completed Jewish
household survey averaged approximately 17.2 minutes.
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